- 2 days ago
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Listening to our listeners (and viewers), this topic came from you guys: Kevin and Mark take a look at motorcycle rear suspension starting with "all arm and no swing" rigid frames of the early days to the many variation on the swingarm as we know it today. A sprung saddle is "rear" suspension, no?
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Listening to our listeners (and viewers), this topic came from you guys: Kevin and Mark take a look at motorcycle rear suspension starting with "all arm and no swing" rigid frames of the early days to the many variation on the swingarm as we know it today. A sprung saddle is "rear" suspension, no?
Become a Channel Partner: https://octanemedia.co/home/become-an-advertiser/
Listen on Spotify: https://open.spotify.com/show/6CLI74xvMBFLDOC1tQaCOQ
Read more from Cycle World: https://www.cycleworld.com/
Buy Cycle World Merch: https://teespring.com/stores/cycleworld
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SportsTranscript
00:00:00Hey, it's the Psycho World Podcast. I'm Mark Hoyer. I'm the editor-in-chief, and I'm with Kevin Cameron, our
00:00:05technical editor. I will tell you the topic shortly. I want you to, let's say, I want to ask you
00:00:10to join us on Patreon. There's a link in the description. We are doing extra episodes and extra content. We've
00:00:16been delighted and really enjoy spending our time with you. We want to do more and extra content.
00:00:22It's a small fee to subscribe and get a lot of behind-the-scenes stuff, and then a couple additional
00:00:27podcasts per week on different topics, some short-form stuff. There's one that we have recently recorded based on an
00:00:34email chain that Kevin and I shared a number of years ago. It was called The Excellence of Butter. Now,
00:00:39it's motorsports-related. Don't get me wrong. We'll always bring it back. I think we'll always bring it back.
00:00:45But we plan like a video shop tour of Kevin's space, and there'll be Q&As at some point in
00:00:51the future. Join us on Patreon if you really like it. Share this podcast with a friend. We're going to
00:00:55keep doing this every Wednesday on YouTube and Spotify. So suffer the commercials. Everything will be available on Patreon without
00:01:04commercials. So that will be one benefit of having a, call it a direct relationship with us, and we'd appreciate
00:01:13anybody who joins us there.
00:01:15And we certainly enjoy you here. So now, let us begin, Kevin. I will say, yeah, motorcycle suspension. In the
00:01:25beginning at the rear, we're going to talk about rear suspension. In the beginning, it was all arm, no swing.
00:01:31We had sprung saddles. Those were, you know, useful. And American bikes had huge cross-section tires.
00:01:37Yes. And that was also useful. As an owner of a rigid motorcycle from the 30s at one time and
00:01:47a swinging arm, the first swinging arm motorcycle of Velocet in 1954 for the 500cc bike.
00:01:56I have to say, I have to say, I could understand the mistrust of a swinging arm at that time
00:02:01because they were not fully baked. And a rigid on a smooth road felt fantastic. Very positive and wonderful.
00:02:10Nothing steers like a rigid.
00:02:12Yep. It really, it's true. Your steering head is so beautifully connected to the rear axle. There's no weave wobble.
00:02:21When you look at early swing arms, it's just, gosh, we'll get to it. But I'm going to kick it
00:02:27to Kevin and let him tell us what's up.
00:02:30Okay. Well, there were some bikes built before World War I with swing arms because that was the period of
00:02:43trying everything. So many people building things, so many different ideas. It takes time for design to settle on something
00:02:54that is workable, affordable, reliable.
00:02:58So I think Indian had a swing arm as an option around 1912. But all attempts to make swing arm
00:03:09bikes in those early days met with derision.
00:03:13Nothing steers like a rigid, said the experienced people, for the reasons that Mark gave, that the frame goes straight
00:03:25from the steering head back down to the axle holders.
00:03:32So people just made do with that. And the idea of large section tires, it did spread to Europe as
00:03:41well. There were three and three and a half inch section rears in use.
00:03:46And there was some, you know, it made the sharp points of the bumps less able to puncture your composure.
00:03:59So things went along like this. And then in 1935 came a sudden slap, which was Goetze built a swing
00:04:17arm version and a triangulated swing arm version of their wide angle V-twin, 120 degrees between cylinders.
00:04:27And won the senior TT, or I should say Stanley Woods, won the senior TT on this bike.
00:04:34And it wasn't a sweeping victory. It wasn't a resounding triumph for the new concept.
00:04:44Norton was always there. They were close.
00:04:48It has been claimed that Goetze knowingly deceived them as to their intentions to when to make a fuel stop.
00:04:57But after the race, Norton's race manager, Joe Craig, said,
00:05:05I believe Stan Woods could not have made those lap times on a rigid bike.
00:05:12Now, that was that was quite a thing at the time because motorcycle design was well accepted as it was.
00:05:22And.
00:05:24News people, interviewers from the British comics would ask questions like,
00:05:30do you think that motorcycles have now reached the limits of human ability?
00:05:38This is when they were averaging 60 miles an hour around the Isle of Man course of 37 and two
00:05:45thirds miles.
00:05:46And now the lap record is over 130 miles per hour, more than twice as much.
00:05:57So Norton immediately adopted sliding pillar.
00:06:02I like to call it sticking pillar because you imagine these these bearings sliding on these two columns that are
00:06:10in an apparatus that is basically welded to the remnants of a rigid frame.
00:06:17And is it all perfectly aligned as the thing slides up and down or does it kind of work its
00:06:23way up and down?
00:06:26But at the same time.
00:06:29Phil Vincent, Phil Vincent, who occupied his school days, drawing pictures of motorcycles and his ideas about them,
00:06:37had bought the failed company of Howard Davies, Howard R. Davies, the HRD of Vincent HRD, which was the company
00:06:49name for a while.
00:06:51And he didn't buy much besides the name and some frame fittings.
00:07:00So had to make up the whole thing.
00:07:03And by 1935, they had built a motorcycle that finished seventh in the same race that Stanwood's won with Phil
00:07:23Vincent's idea of a triangulated swing arm rear suspension.
00:07:28So the same idea, maturing in two places simultaneously.
00:07:34And this is so often the nature of innovation.
00:07:39Linus Pauling was within weeks of coming up with the structure description of DNA as the double helix.
00:07:53But it was another team that got there first, because when you have a lot of people working on a
00:08:00problem,
00:08:01stymied by the lack of a solution and spending a lot of time thinking about it,
00:08:10often the solutions will be similar.
00:08:13So that was the end of nothing steers like a rigid, because suddenly here is Joe Craig saying,
00:08:26I don't believe old Stan could have made those lap times on a rigid part.
00:08:33So big change.
00:08:37Now, we have to sort of leap from this point.
00:08:42World War II, the military is very conservative.
00:08:47They want single cylinder flatheads with rigid frames, because that's what they'd always had.
00:08:53So that's what they built for them.
00:08:56The war ends.
00:08:58Motorbike racing resumes.
00:09:01Norton is trying to make its ages old by this time, but wonderfully developed single cylinder 500 double overhead cam,
00:09:12two valve engine.
00:09:15Wind races continue successful in the TT.
00:09:19But Chilera and in 1950 MV are fielding four cylinder bikes,
00:09:27which made their RPM not by super refined airflow and combustion, but by raw RPM.
00:09:37Do the power producing cycle more times per minute.
00:09:45So Norton had a problem.
00:09:49Their garden gate frame was a single plane frame.
00:09:53There was excessive stress on the down tube, which on occasion would just click, break off.
00:10:00One writer called it, it broke like a carrot.
00:10:05If you've ever broken a carrot, it makes a very decisive sound.
00:10:11And so Norton is looking high and low for a solution.
00:10:18And they were aware, or were made aware, that two brothers up in Northern Ireland, Rex and Chromie McCandless,
00:10:29had come up with something.
00:10:30They were putting swing arm rear suspensions on people's motorcycles as a update.
00:10:38And they were working intensively, developing their own motorcycle chassis with a Triumph Twin engine in it.
00:10:49With some radical features, twin loop frame, enclosing quite a lot of volume.
00:10:56A twin loop frame is a wonderful thing to attach a swing arm to because the swing arm fits between
00:11:02the loops at the back
00:11:05where they're descending to curl forward under the engine.
00:11:08And you have reinforced areas there.
00:11:10The swing arm fits in between.
00:11:12You slip the bolt through.
00:11:14It's gripped out wide.
00:11:15Wide.
00:11:17Wide, wide.
00:11:18It's a lot better than...
00:11:19Instead of a tube, the seat tube sticking up like this with the swing arm attached to it going...
00:11:26Yeah.
00:11:27Vestigial suite seat tube because we weren't using them.
00:11:30But, you know, I hate to say Velocet, but the swinging arm 500 MSS and every Velocet after that had
00:11:38a vertical tube.
00:11:39And the swing arm's attached to that in a lug.
00:11:41And then that pipe is unsupported out here.
00:11:45And to add entertainment to that, so the pivots there and on the pivoting tube, the two arms for the
00:11:51swing arm are clamped.
00:11:54Not welded.
00:11:54Little pinch bolts.
00:11:55Clamped.
00:11:56Not welded.
00:11:56They're slid on.
00:11:57So, A, you better make sure they're lined up pretty good and everything is nice.
00:12:01But, yeah, it's...
00:12:02And a Velocet for that era especially is a pretty decent handling bike.
00:12:06But we'd have a lot better.
00:12:10Let us compare the rubber in tires with the rubber used in hard rubber combs.
00:12:21Because tire grip and the ability of the suspension to ride up and down over the undulations in the pavement
00:12:31generates the forces that the frame has to handle.
00:12:36And those forces were weak and flabby at the time.
00:12:40So, they get their prototype running really well, testing daily on the public highways of Northern Ireland.
00:12:49And this is a wonderful story because this is not a drawing board story.
00:12:55This is not a computer or AI story.
00:12:58This is two guys doing it.
00:13:02And Rex worked at Shorts Aviation up there.
00:13:09And he had learned about low-temperature silver brazing, which allows you to join steel tubes without heating them to
00:13:20red temperature and, therefore, destroying their heat treat.
00:13:25So, this was one of the things that he was, he had made himself familiar with.
00:13:29He's a man who left school at the age of 13 because he wanted to do things.
00:13:36He didn't want to sit there waiting for other people to learn to spell.
00:13:43Perhaps you've had similar experiences.
00:13:46In any case, Rex McCandless is summoned to Bracebridge Street.
00:13:54And he agrees to build Norton a chassis.
00:13:58He builds it.
00:14:00The motorcycle, by the way, he had to bring his whole brazing setup because there was no welding equipment at
00:14:07Norton.
00:14:09No welding equipment in the factory because this was the days of tube and lug.
00:14:15The lugs are cast iron or steel and the tubes are slid into holes machined in these lugs with a
00:14:24sort of a lick of brazing spelter.
00:14:29The whole thing goes into an oven.
00:14:32The brazing spelter melts and joins everything together.
00:14:37There's your frame.
00:14:38The videos of the production of that, there was a Triumph Factory.
00:14:42I think it was the Triumph Factory video where they put the lug in.
00:14:45It's big hammers.
00:14:46This guy wearing a leather apron.
00:14:50And he's sticking it into a forge.
00:14:54You know, and he's pumping away and it's probably a coal forge and it's just there.
00:14:59And he just jams the thing in there, melts that stuff.
00:15:02Goes all the way around the frame, builds the frame, and then hits it with a giant hammer to straighten
00:15:07it out before he sends it down the line.
00:15:09It's nice.
00:15:10Look that up.
00:15:10It's out there somewhere.
00:15:12Triumph Factory, 1950s.
00:15:13This was to be named the Featherbed Frame because riding it in comparison with the previous frame was like lying
00:15:24on a feather bed.
00:15:27This silver brazed chassis was built up into a motorcycle and Norton tested it every which way.
00:15:33They ran it in the Isle of Man.
00:15:35And they found there that it could pass another rider on the garden gate frame on the outside, accelerating.
00:15:47I think someone must have written that down soberly on a pad.
00:15:52Got to get one of those.
00:15:55Yes, sir.
00:15:56Then they tested it at the Motor Industries Research Association, MIRA, test track in England.
00:16:04And after that, they tested at Mollery, which was a speed bowl outside of Paris.
00:16:10Thorough testing.
00:16:11Like Davy Crockett said, first, be sure you're right.
00:16:15Then go ahead.
00:16:20So they run this thing.
00:16:22Jeff Duke is the rider.
00:16:24What could be better?
00:16:27And it was a huge success.
00:16:29Yes, they would have won the 500 World Championship in 1950 had they not had tire failures caused by throwing
00:16:38the tread off the tire, chunking.
00:16:43And so in 1951, with a different brand of tire on their bicycle, they defeated Jalera and MV, four-cylinder
00:16:57bikes, with the good old Norton Single.
00:17:01And this was a motorcycle with a telescopic fork up front, a swing arm in the back, twin-loop frame,
00:17:09and hydraulic damping all around.
00:17:13No more squeaking, stick-slip, scissors-type friction dampers with a big wing nut to adjust the damping.
00:17:27Well, that description you made of the twin-loop frame and all that is the recipe we used racing-wise
00:17:33until the 80s, really.
00:17:36Oh, for many, many years.
00:17:37Yeah, I mean, it is.
00:17:38This was it.
00:17:39This was the new synthesis.
00:17:41All these ideas had been tried before.
00:17:44But when I looked at the drawings, I looked at photographs, I could see that the engine had been moved
00:17:51forward like three inches, and the rider nearly the same.
00:17:58So no wonder it could accelerate around the outside of the Garden Gate motorcycle.
00:18:07Anyway, of course, it couldn't last.
00:18:13The Norton just didn't have the power to keep up once Jalera and MV started, and this was the term
00:18:22they used, Nortonizing their chassis.
00:18:26Try to imagine a 500cc four-cylinder motorcycle with 32-millimeter fork tubes.
00:18:35If they're bent, you could probably straighten them over your knee, do you think?
00:18:41I'd try.
00:18:42Yeah, or at least banging them into a tree.
00:18:45That's sure to work.
00:18:46It was a traditional remedy for on-the-road repair.
00:18:52Slow them in a door.
00:18:53Yes, inertial truing.
00:18:57So what happens now is that the swing arm is widely adopted because there's no longer any reason to consider
00:19:09the alternative sticking pillar.
00:19:13I think there was a system where they terminated the rigid frame early and put little six-inch long swing
00:19:22arm on there.
00:19:25Oh, the Triumph Sprung Hub is legendary.
00:19:27The Spring Hub.
00:19:28Oh, oh, oh, yes.
00:19:30Now, just one last bolt here.
00:19:33Suddenly the thing explodes in your face.
00:19:35Oh, yeah.
00:19:35The imprint of springs on your eyes and in your mouth and so forth.
00:19:40Yeah, my friend Bill Getty, he's a JRC engineer and he does British parts and stuff.
00:19:45He's been working on British bikes his whole life.
00:19:47Big enthusiast and a crazy rider and lots of great adventures.
00:19:51And he's taken apart everything.
00:19:52He can recognize across the room the body of a British generator skittering across his shop and say, oh, wait,
00:20:00we got to get that.
00:20:00That's a really rare XYZ off a 1953 one-year aerial mag dyno setup or something.
00:20:07It's just remarkable.
00:20:08And he says, if you ever get a Sprung Hub, don't take it apart.
00:20:13That is what they say.
00:20:15So the Sprung Hub is a giant hub and it has springs inside.
00:20:18So they just slid this thing into the Ridge and Triumphs of the day, you know, sort of 1950-ish.
00:20:23It had guide shoes inside of it.
00:20:24Yeah.
00:20:25And it had a little arc that it would run through and a lot of springs holding it.
00:20:29And it did, you know, it's got a feel, seemed to work sort of okay, half measure.
00:20:35I think of the rigid as a triangulation that I would want to extend.
00:20:41That's my dog.
00:20:43The triangulation is something I would want to extend to a swing arm, you know.
00:20:49Hound of the Baskervilles.
00:20:51Yeah.
00:20:53Yeah.
00:20:54Come.
00:20:58Sorry, folks.
00:20:58It's my dog.
00:20:59I know people have requested.
00:21:00Come here.
00:21:01Oh, you don't know.
00:21:02Okay.
00:21:02So anyways, yeah, just that triangulation of the rigid, I think is, I wish we'd extended that sort of the
00:21:10way that, you know, Vincent did.
00:21:12What if we had done that from the beginning for everything?
00:21:16Yes.
00:21:18Well, something else was easier to do and worked just as well in general.
00:21:26Certainly, as soon as the feather bed came along, alternatives were discouraged.
00:21:34Anyway, this era of three pieces of pipe went on for years because it was enough.
00:21:50Tires had cotton carcass for right through the 50s, and then rayon and nylon and other alternatives were adopted, made
00:22:04the tires a little more durable.
00:22:09And butadiene styrene rubber, synthetic rubber, was beginning to be adopted in the late 50s.
00:22:17And I remember the Avon tire made with cling rubber, I think.
00:22:23And everybody had this improved form of rubber on tires by the early 60s.
00:22:33So forces on the suspension were on the increase, but not very rapidly.
00:22:41So along comes Suzuki with an interesting idea.
00:22:46Their 50cc racer needed to have its weight reduced essentially to zero because it only had 14 and a half
00:22:57horsepower.
00:22:58So they made the frame and the swing arm out of aluminum.
00:23:03What a novelty.
00:23:05Now, this resulted in Hugh Anderson characterizing it as this.
00:23:15There was quite a difference in characteristic between the aluminum and the steel frames.
00:23:21On the fast corners, the aluminum frame was quite good, but on the slower ones, it was quite rigid.
00:23:30And he goes on to say basically that the flexibility of the steel frame was an asset in slower corners
00:23:41and the stiffness of the aluminum in fast corners.
00:23:45Well, steel is three times stiffer than aluminum.
00:23:49That is, its inherent spring constant, Young's modulus.
00:23:54How can the weak material produce a stiffer frame?
00:24:02And so, and of course, today you hear these same things about bicycle frames.
00:24:07Oh, aluminum is way too stiff for me or what have you.
00:24:12Well, it turns out that for a constant wall thickness, if you increase the, as you increase the diameter of
00:24:22the tubing,
00:24:24the stiffness of the tubing, that is resistance to bending, I should say, increases as the fourth power.
00:24:34So, this means that if you increase the diameter by 10%, you're going to end up with three or more
00:24:47times the rigidity, the stiffness, pardon me.
00:24:51So, I think they were simply saying, well, we can make, we can use larger aluminum tubing to compensate for
00:25:02the fact that it isn't as stiff as steel.
00:25:04Well, and they were very successful in doing that.
00:25:07I think they also put aluminum swing arms on, on their 125 V4, which at one point was making 40,
00:25:1640 odd horsepower.
00:25:1840 odd horsepower from a 125 is fairly good going, especially for the mid 19, mid to late 60s.
00:25:36So, Yamaha decided, okay, the round tube is a problem because if we want to make it stiffer and we
00:25:47make the diameter bigger,
00:25:49then the whole thing becomes wider, the shocks have to be mounted out farther, why don't we make the swing
00:25:56arm beams out of rectangular tubing, taller and narrower?
00:26:03So, they did.
00:26:04And I think it was 63, they put a rectangular swing arm on their RD56, which Phil Reed then in
00:26:1464 and 65 took to 250 World Championships.
00:26:20And that chassis came to the U.S. in 1969 on the TD2 and TR2 production road racers, two strokes,
00:26:30both of them, with that rectangular tube swing arm.
00:26:37Now, I remember seeing those swing arm dented by, I don't know what, stones kicked up by the front tire?
00:26:47I can't say, but there wasn't a lot of thickness in those tubes.
00:26:54And Don Vesco and others in California began to make rectangular tube swing arms.
00:27:03And there was a favorite size, I think, about two inches high by an inch wide that most people were
00:27:11using.
00:27:11I think Vesco's were rather less tall.
00:27:14He was going for low weight.
00:27:16Others were going for high stiffness.
00:27:19And there was a lot of discussion of swing arms.
00:27:22And around 1970, handling problems with 250s and 350s seemed to smooth out with a longer swing arm.
00:27:34And in 1971, this phenomenon peaked.
00:27:37Just put a longer swing arm on it.
00:27:39It's going to be great.
00:27:40And when Kelk or others went to Japan to test ride the TZ750A, which many people called TZ700,
00:27:54it weaved on the straightaway at the test track where they ran.
00:28:01And Kel said, extend the swing arm three inches.
00:28:06So it was done.
00:28:09And probably they had given it Agostini's favorite swing or wheelbase of 53 and a half inches.
00:28:18And they added three inches to that.
00:28:22So that was working.
00:28:26So at this point, Harry Hunt threw his hat in the ring.
00:28:32And he made a swing arm that was seen from the side.
00:28:37Here's the pivot.
00:28:39And here's the axle holder.
00:28:41And from the pivot, it filled completely the space below the drive chain.
00:28:51So it was a very tall beam.
00:28:55And then it tapered to the axle holders.
00:28:59This was, I think, the high point of the, what I would call simple swing arm.
00:29:10And I designed one like that for my riders, TZ750.
00:29:16And the welder putting it together laughed at it.
00:29:20He held up a piece of the sheet metal and flopped it back and forth.
00:29:24It was bending.
00:29:26He said, this, this can't work.
00:29:29Please weld it together.
00:29:31Then we'll see.
00:29:33And of course, not only was it massively stiff, but it cracked from lateral forces.
00:29:42Yeah, isn't that how it ends up?
00:29:44But we've got to try it, you know.
00:29:46That's the thing about sheet metal, though, is boxing it in, you get something.
00:29:52You get a structure with dimension.
00:29:54If you take a flat piece of sheet metal and you make it into a bowl, make it a dome,
00:29:58put any crown in it, it's quite rigid.
00:30:01Yes, indeed.
00:30:02That's why body panels are typically curved.
00:30:05And that's why Vincent, Phil Vincent, was told, dish all sections when he was designing, when he and Phil Irving
00:30:13were designing the post-war twin.
00:30:17Dish all sections.
00:30:20Shape brings stiffness.
00:30:22The cardboard box is unimpressive until you close the flaps and tape it, and then it becomes quite rigid.
00:30:35Anyway, here comes 1972.
00:30:38The AMA had made a new rule, effective 1970, that said no more special deal for flatheads, no more limitations
00:30:50on how many gearbox speeds you can have.
00:30:54Everyone gets 750 cc's, two-stroke, four-stroke, flathead, whatever you like.
00:31:01And in 1972, here comes Kawasaki with their 90-horsepower H2R and Suzuki with their TR750 100-horsepower liquid-cooled
00:31:12triple, aka, what was it now that they called it?
00:31:19With water buffalo?
00:31:21Water buffalo, that was it.
00:31:23Because of its—the buffalo part of it, of course, referred to the handling.
00:31:28And there were so many theories about that.
00:31:30Well, if we just put a piece of tubing in here, or—
00:31:35Well, I rode one of those two-stroke street machines that we call a water buffalo also, and it was
00:31:41a really nice motorcycle.
00:31:42Actually, it turned out to be very nicely tuned, and it was a very tractable engine, and it was quiet.
00:31:48You know, the rotary was insanity by comparison.
00:31:52But the people in the showroom couldn't understand what it was for.
00:31:57Yeah, absolutely.
00:31:57It had no legend.
00:32:00It did not.
00:32:01If you create a huge monster, and it has no legend, it's just a statue.
00:32:08There's got to be a story.
00:32:10We humans want the story.
00:32:13So—
00:32:14Work for the Hayabusa.
00:32:16Yeah.
00:32:19These motorcycles brought 100 horsepower to road racing for the first time.
00:32:25They could exert such force through the swing arm that no tire could be found for those motorcycles.
00:32:35So, in 72 and 73, the Daytona 200 was won by a little Yamaha 350 twin, which was easy on
00:32:44the rider, easy on tires.
00:32:46The rider went to the party after the race and not to the therapy clinic.
00:32:55Now, along comes a series of changes to motorcycles, which greatly affected their grip and the way people rode them.
00:33:10From motocross came a long travel suspension.
00:33:16Why would you want to increase the travel?
00:33:18So that you have to get on your motocross bike by standing on a five-gallon pail?
00:33:24Probably not.
00:33:25The real reason is that the energy absorption capability of suspension is proportional to travel squared.
00:33:39So, the old-time bikes, which, since 1950, since the Featherbed, switched everything to hydraulic damping, three inches of travel.
00:33:52All those wonderful girling shocks that British riders brought to Italian race teams in their luggage because they didn't trust
00:34:00any other form of suspension.
00:34:04I think those people had to contain themselves because prolonged vibration increases the urge to pee.
00:34:18So, this long travel suspension to this was added slick tires.
00:34:32First, long travel, I was told by Mike Baldwin, he said, on those old bikes with the short travel stuff,
00:34:39when you rode out of the Daytona infield at turn five onto the banking, there was a pronounced thump.
00:34:48And there was nothing you could do about that.
00:34:50So, that was a good place to upshift because suspension upsets are made smaller by not having the power on.
00:35:00But he said, as soon as we got the long travel stuff, you could just gas it through there.
00:35:07So, the ability to gas it through rough sections meant more thumping and twisting and banging, passing through the swingarm.
00:35:23So, this was a time when something more was needed and everyone was recognizing it.
00:35:34The grip of slick tires was just tremendous.
00:35:38First of all, the tread was self-bracing.
00:35:40It didn't have little weakening grooves cut in it to make the tread flex from side to side and the
00:35:49tread blocks tip so that their surface in contact decreased.
00:35:54Oh, Kevin, the first time I tried slick tires, I could not believe it, especially the front.
00:36:01Turning in the smoothness and the feedback and the positivity.
00:36:05It was amazing.
00:36:08It really was.
00:36:09So, yeah, every time you make a void in the tread, even that fancy stuff that you get, all these
00:36:13DOT race tires with the notional water sipes on them.
00:36:16Yeah.
00:36:18The little, like one every eight inches.
00:36:20I think it looks like Arabic writing, yeah.
00:36:22A little squiggle.
00:36:24Yes, a little squiggle.
00:36:26I mean, they're really close to slicks, but they're not slicks.
00:36:32So, people began to add some bracing to swing arms in a kind of, gosh, I wonder if it would
00:36:38be better, you know, if it were stiffer.
00:36:40So, either on the top or the bottom of the swing arm, they'd glue on, weld, tubular braces, the purpose
00:36:50of which was to prevent the swing arm beams from doing this.
00:36:55Yeah.
00:36:56And the tire from tilting from side to side, because you know from holding a bicycle wheel and spinning it,
00:37:03that if you try to yank it, it does something that is just completely unpredictable until you get used to
00:37:11it.
00:37:12And motorcycles can tie themselves in knots from those forces.
00:37:19So, here comes Superbike.
00:37:22AMA first called it heavyweight production, because there were so many people racing these new 1,000cc, 903cc four-strokes
00:37:33that the AMA said, well, we've got to make a class for that, because that's coming.
00:37:39So, they did that, and that became Superbike.
00:37:46And these were motorcycles that were powered by engines that were twice as powerful as a Triumph Bonneville in a
00:37:57chassis whose technology level was identical with that of a 60s Bonneville.
00:38:07And when Japanese engineers were asked why they had done this, they said, oh, in the U.S., 60 mile
00:38:16per hour speed limit.
00:38:17So, were you ever young?
00:38:23Did you ever break a rule?
00:38:26Have you heard of breaking rules?
00:38:29Anyway, they quickly learned that those big motorcycles needed a lot of help.
00:38:39Welding in of all kinds of braces and gussets and pieces of plate, the whole, all the tubes going up
00:38:46to the steering head were sheeted in to make a stiff box out of it.
00:38:50And the AMA, in a rare departure from their usual tight-lipped conservatism, said,
00:39:04Swing arm and fork and suspension damping parts may be altered or replaced.
00:39:12And a loud rattle from the dumpster as all those parts fell in after flying across the shop.
00:39:21It recalls the classic R90S, the Butler and Smith bike, where it was a twin shock motorcycle from the factory
00:39:29and suddenly sprang monoshock.
00:39:31Yes, because Udo said, we relocated one of the shocks to a shelf in the shop.
00:39:41So, it's perfectly legal.
00:39:43Good stuff.
00:39:44So, this first era of Superbike was very attention-getting because these bikes all wobbled and weaved and the riders
00:39:55sat up and you could see their grim efforts to assert control over 400 plus pounds of hurtling iron and
00:40:03aluminum.
00:40:05Well, that era came to an end after 1982 when the displacement was changed to 750.
00:40:15Second era of Superbikes were given some of the knowledge, some of the results of the Big Four experience in
00:40:27motorcycle road racing, Grand Prix racing specifically.
00:40:30Oh, we have to do chassis differently.
00:40:34We need improved fork.
00:40:36We need better swing arm.
00:40:39And the AMA saying, altered or replaced, modified or replaced, people just started welding stuff onto swing arms like crazy.
00:40:50And no more three pieces of pipe.
00:40:55It became the standard thing for all race bikes to have a tower built either on the top or on
00:41:01the bottom of the swing arm, whose purpose was to prevent this.
00:41:06Let your swing arm do the walking?
00:41:08No way.
00:41:09So, they produced this second generation of sports motorcycles to be raceable as delivered.
00:41:22And the result was production racing classes of a new and powerful, irresistible kind, super sport.
00:41:32Because it was estimated at that time that the modifications permitted would cost you no more than $2,500.
00:41:41And this was at a time when the cost, the price of a TZ250, which used to be the first
00:41:48step into professional road racing, was sailing past $20,000.
00:41:55And you could buy a 600 super sport for not much more than that $2,500.
00:42:01Yeah.
00:42:02I was, this is a note on the production racer front.
00:42:06I was looking at race results circa 74 from Laguna Seca.
00:42:11We have a really nice picture of Yvonne Duhamel racing his number 17 there.
00:42:16But I went back to the results.
00:42:17This is in Cycle World, an old issue of Cycle World, November 74, as I recall.
00:42:23And, boy, the results are stacked with Yamahas.
00:42:28It's just every class.
00:42:30And there's Duhamel behind Ken Roberts, learning a heartbeat away from becoming one of the greatest road racers practicing the
00:42:40craft at the time, said the story.
00:42:42And he was.
00:42:45Because these sport bikes changed the attitude of American riders.
00:42:53The Honda Interceptor 750 sold 1,200 bikes in the twinkling of an eye.
00:43:00I think that's, what, one bike per dealer?
00:43:04Maybe slightly more than that.
00:43:06But at any rate, handling had never been an advertisable or even a detectable quality in terms of marketing.
00:43:17And all that you would see, yes, all you could see was, what's the top speed, man?
00:43:23What's the quarter mile time, man?
00:43:26And so our magazines delivered that information.
00:43:34And so these redesigned motorcycles had improved chassis.
00:43:42They were stiffer.
00:43:43Same thing was happening in MotoGP, 500GP as it was then.
00:43:51That when a rider began to get on the gas to come off a corner, a more flexible motorcycle would
00:43:59go through this tremendous cycle of oscillation and jumping sideways as the tire lost as it slipped and gripped and
00:44:11slipped yet again.
00:44:15And for a time, making the chassis stiffer, shortens the recovery period.
00:44:21Yes, the tires still slipped and gripped.
00:44:24Yes, there were still oscillations.
00:44:26But now they were calmed somewhat.
00:44:35But stiffness became a god.
00:44:38And we threw ourselves on our faces and worshipped it.
00:44:44It was a false god.
00:44:48In 1993, after practice at the post-practice press conference, Wayne Rainey said, we have chatter, we have hop, and
00:44:59we have skating.
00:45:00We don't know what to do about it.
00:45:04Now, since the beginning of time, since the beginning of the bicycle, lateral flexibility in a two-wheeler going through
00:45:14a curve has functioned as a form of suspension.
00:45:23So instead of just launching yourself from crest of one undulation to the crest of another, there was some chance
00:45:33that the tires would follow the contour and remain gripping.
00:45:39And people thought this through.
00:45:42And by 93, there had been some people who had said, what if we just cut that cross member out?
00:45:48Let's try it.
00:45:49We can always weld it back, right?
00:45:52And sometimes it was better.
00:45:54Other times it was a disaster.
00:45:56So people didn't establish lack of flexibility, a lack of stiffness as a new god.
00:46:05They were just confused because the results weren't consistent.
00:46:12Well, then came this tremendous period of experimentation.
00:46:24And all sorts of things were being tried in hopes that one of them might work.
00:46:32In the midst of all of this, here comes Honda with RC30 in 1987 with a single-sided swingarm.
00:46:42This was, I think, the first production, you know, over-the-counter bike with a single-sided swingarm.
00:46:50The idea had come from Honda's association with Elf, a French fuel company that had done a bunch of experimental
00:46:59chassis with alternative forms of suspension and structure.
00:47:04Elf were the ones, for example, who came up with the idea of putting the fuel under the engine instead
00:47:10of on top.
00:47:13At this point, the single-sided swingarm was not fully mature.
00:47:24A conversation that I had with American Honda Racing Manager Gary Mathers, he said he told me the place to
00:47:32go at Willow Springs,
00:47:34which is used by the manufacturers for testing all sorts of stuff.
00:47:39Go up there and sit when we have a test day and look at the RC30 going through there, and
00:47:45you will see stress asymmetry.
00:47:51Because if you've got one beam holding the, with an axle sticking out of it, fairly hefty axle, and there's
00:48:01nothing on this side,
00:48:02then there are increased degrees of freedom.
00:48:07The axle can do this so that all sorts of crazy stuff was going on at the time.
00:48:15Well, people loved the single-sided swingarm because it was so different.
00:48:20And it looked like...
00:48:20Oh, we loved it.
00:48:21I mean, we had to have it.
00:48:23Yeah, it looked like Formula One car parts.
00:48:26Well, I bought a VFR 750 Express.
00:48:28I mean, there's no way I could have bought an RC30.
00:48:30You wanted an RC30, but then they made the VFR 750, and it had gear-driven cams and had a
00:48:36single-sided swingarm.
00:48:38And that was the sliver of the True Cross that I could afford, and that's the new bike that I
00:48:42bought in 1995.
00:48:44I've got to have it.
00:48:45You've got to.
00:48:47So, of course, every innovation has a learning curve.
00:48:53Ducati, well, let's say Massimo Tamarini, the great and intuitive designer, adopted a single-sided swingarm for the 916.
00:49:11And it was as if he had conferred immortality upon all who looked upon this motorcycle.
00:49:20They wanted it.
00:49:22They wanted the single-sided swingarm, and they continue to want it.
00:49:26And I would make a parallel with the Porsche 911, which Porsche have repeatedly tried to discontinue, because it has
00:49:37the engine sticking out the back of it, as if someone said,
00:49:41you know those modified Model Ts they used to have at the fair?
00:49:45When the guy would gas it up, the front wheels would come up, and the kids inside would squeal with
00:49:51delight.
00:49:52Let's build a car like that.
00:49:53We'll make the engine stick out the back.
00:49:56And people loved that car, and they continue to love it.
00:50:01So, this must simply be accepted.
00:50:10And poor old Pierre Terblanche with his—what was the model that he made?
00:50:19Oh, the 999.
00:50:20Yes, the 999.
00:50:24He deviated from the true path.
00:50:28Well, there was a lot—yeah, there was a tremendous deviation.
00:50:30He was very much into—he's like a cerebral designer.
00:50:34I mean, he did—you know, he's credited with the super mono.
00:50:38And, you know, he did some interesting stuff.
00:50:40He did the Halewood.
00:50:41You know, Halewood.
00:50:41People really liked that Halewood quite a bit.
00:50:45I mean, it wasn't comfortable, but who cares?
00:50:48It looked fantastic.
00:50:50And then the 999, it was very cerebral.
00:50:53And, you know, the Ducati thing is emotional.
00:50:56It's very, you know—
00:50:57Exactly.
00:50:58The Tambourini stuff had organic shapes, and it was—I mean, he kind of had said, yeah,
00:51:04the NR750 was part of my inspirational process, and why wouldn't it be?
00:51:08You know, the oval piston and single-sided swing arm there.
00:51:13And then along comes Pierre, and he does—he wants to make a rational—I had a long conversation
00:51:19with him.
00:51:19He wants to make a rational design.
00:51:20And he's like, well, why don't we use enclosed chains?
00:51:24Because enclosed chains, the chains last virtually forever.
00:51:28He says, people just don't like it.
00:51:30And he was mad.
00:51:31You know, like, he was mad.
00:51:32Like, why can't they understand?
00:51:33Why can't they understand?
00:51:35And it's like, well, you know—
00:51:36Get them by the lapels and give them a good shaking.
00:51:39Then they'll believe.
00:51:40You know, it's like—it's like rock and roll, you know?
00:51:43It's not rational.
00:51:45We're not—
00:51:45You like what you like.
00:51:46We're not using—we're not using good grammar.
00:51:48It's the who.
00:51:49It's not the whom.
00:51:50You know, we pound it out, right?
00:51:53Like, you—like, it just shreds.
00:51:55And so the 999 comes along, and we had a conversation about it.
00:51:58And he said—I said, well, the single-sided swing arm, I mean, you know, it's kind of
00:52:03a trademark.
00:52:03And he's like, yeah, but it doesn't work.
00:52:05I mean, tell me why it doesn't work.
00:52:07It doesn't work.
00:52:08We tested it with a twin fork swing arm, and the lap times were faster.
00:52:11We had to use it.
00:52:12We had to use a twin arm.
00:52:14And Ducati is now using a twin arm.
00:52:16They are.
00:52:17I mean, now it's okay.
00:52:19Back then, it wasn't okay.
00:52:21And then I ran into Bart, who was Bart Johansson Grossbeek, I think it is.
00:52:28He was a designer at Ducati at that time.
00:52:32And he was part of the team that did the 1098, which was—which I found out recently sitting
00:52:37at dinner with him in Germany last year.
00:52:41I said, you know, I always took—I always took the 1098 as like a conservative apology
00:52:46to the Ducatisti to come back.
00:52:48It was just—it was just nice.
00:52:50It wasn't flamboyant, but it had—it had what we wanted.
00:52:54And you got the single-sided swing arm.
00:52:56He's like, absolutely was.
00:52:58You know, like we just—we got to be cool.
00:53:00We got to kiss and make up.
00:53:02And that's what they came back with, single-sided.
00:53:04They're like, make it work.
00:53:08Well, when they decided that you could have too much stiffness, they wanted to know naturally
00:53:15which stiffness.
00:53:16Bending stiffness?
00:53:18Torsional stiffness?
00:53:19Lateral stiffness?
00:53:20They quickly decided lateral stiffness.
00:53:24And prototypes were built to allow these variables to be explored.
00:53:31And lateral stiffness reduced—or I should say relaxed—lateral stiffness became a tool.
00:53:40That's still being used.
00:53:42And to my knowledge, there is not an SAE paper that has been given by Honda or any of the
00:53:48others.
00:53:48There used to be lots of SAE papers by Honda, but they studied the daylights out of it.
00:54:01And to the point of maybe occasionally a drive chain running off, that would be quite a lot of lateral
00:54:10flexibility.
00:54:12The whole front of the frame was made into a lateral spring, carrying the steering head and the fork and
00:54:20all those tremendous unsprung weight,
00:54:23but better than a rigid bike, as Casey Stoner discovered when Ducati built that carbon fiber frame.
00:54:35The front end was so stiff that it did not send information to the rider, and as a result, he
00:54:43had to guess how fast he could go into a given corner.
00:54:48He had to remember Musk's muscle memory from last lap.
00:54:53Consequently, he began to fall, and his position in the world championship began to fall.
00:55:02And all sorts of theories were advanced, so he had some kind of fatigue syndrome and various problems and so
00:55:10forth.
00:55:10But when Honda said, get on our motorcycle, just as he had done with Ducati in 2007, he won 10
00:55:20races and the championship.
00:55:27And Colin Edwards told me the story of riding the RC-51 when Honda first realized that the Ducati was
00:55:37much more flexible laterally,
00:55:42and they developed a kit of parts.
00:55:45It had a little booklet that came with it.
00:55:47It said first step, second step.
00:55:49And he said, with every step, I could push the bike harder and lap a little bit quicker before it
00:55:57started to chatter.
00:56:00And finally, he said, they had taken out at least one engine bolt and softened up things,
00:56:08allowing lateral movement by means of spacers and shims,
00:56:15such that he could break Bayless and win the championship.
00:56:21And he watched that whole thing happen step by step as they went through the little booklet
00:56:27until the motorcycle had the lateral flexibility to get through corners faster.
00:56:35Now, at an earlier time when I'd spoken to Colin about the Ducati, I'd said,
00:56:42I think it really wallows in the corners.
00:56:45Yeah, he said it wallows, but it digs in and goes around the corner.
00:56:50So the problem was to make the Honda dig in.
00:56:55And they did that.
00:56:58So it's spread to MotoGP.
00:57:04I remember at one point when I managed to finagle my way or be invited into one of the boxes
00:57:11on pit lane,
00:57:13I got a measurement.
00:57:17The lateral thickness of the beams, which are tremendously high at the front
00:57:22and tapering down to the axle holders, 32 millimeters.
00:57:27The next time I had the opportunity, 25 millimeters.
00:57:33Finally, they had them flexing enough to crack,
00:57:38like my experience with my built-up sheet metal swing arm.
00:57:44And then they said, well, let's try carbon fiber.
00:57:50Carbon fiber can flex a lot without cracking.
00:57:53So that's where we are.
00:57:56Yeah, compressed, not compressed sand.
00:57:57That's the old Britain quote.
00:58:01You know, when you start working with directional materials,
00:58:03you start to look at metals like compressed sand.
00:58:07Really tightly packed.
00:58:09So it's got some strength, yeah.
00:58:11Yeah.
00:58:13Yeah, I would say I was looking at a photograph of a Honda MotoGP bike upper triple clamp,
00:58:20and it's like a blade, and the engine mounts.
00:58:23Anytime you see a photo under the skin, if you get that rare photo of a body off on a
00:58:29MotoGP bike,
00:58:30or when they crash.
00:58:30It's just thin sheet metal, yeah.
00:58:31Just little thin sheet metal holding this, you know, 300-horse power engine.
00:58:37And, I mean, you know, here I am riding modified street bikes,
00:58:42or I would say the fastest, most recent super bike-like thing I've ridden is an Alpha Racing.
00:58:49That's BMW's kind of performance house.
00:58:51They do all the preparation for super bikes,
00:58:53and you can buy an Alpha Racing BMW M1000RR prepared for, like, stock 1000.
00:58:58If you want to go race AM8, excuse me, MotoAmerica stock 1000, call Alpha.
00:59:03So I rode Nate Kern's version of this bike, and it was insane.
00:59:07The steering was insane.
00:59:08The brakes were insane.
00:59:09The power was insane.
00:59:10The electronics were out of this world.
00:59:12And he had loaded his bike, Alpha, and this was at Barber,
00:59:15at the end of the 24 season for MotoAmerica, and when I was racing,
00:59:19and they loaded that bike with the program from Jason Uribe's stock 1000 bike.
00:59:25And so all the electronics were, like, ultra as good as they could be in that sphere.
00:59:32And it was, the loads were mind-blowing.
00:59:36You know, I spent the entire week racing a 72, a 72 BMW with 70 horsepower,
00:59:42which was super fun, and it feels as fast as can be,
00:59:45and it handled quite well for what it was.
00:59:47But it's a very human, it's like what you said about the Isle of Man.
00:59:53Have humans reached the limit, you know, 60-mile-an-hour lap time?
00:59:57And I'm, like, breaking 120.
00:59:59I'm going 120 miles an hour, which you could do in about three seconds on a M1000.
01:00:09But the loads are incredible, and I can't imagine what riders are going through.
01:00:14I mean, you can see it when they, you can see it in how their bodies are,
01:00:18and you can see it in what they're doing on the bikes,
01:00:22and how far they're leaning, and how their heads are this high off the tarmac
01:00:28as their shoulders are flat on the ground.
01:00:31And they're wearing protectors on the elbow.
01:00:33Yeah, elbows and shoulders.
01:00:35You're dragging shoulders.
01:00:36Oh, yeah.
01:00:36Well, Martin started that shoulder thing.
01:00:39Well, he may not have, but he certainly got people talking about it.
01:00:42Yeah, but all through this conversation, it reminded me of the progression of racing
01:00:51and some of the stories that you have told.
01:00:54So, oh, great, we have slick tires, and now we've made the chassis stiff enough
01:01:00for that slick tire.
01:01:02But the progression just goes away.
01:01:04If only we would do the same lap times, everything would be fine, right?
01:01:08You know, that's a beautiful progression of racing.
01:01:12That's why it's wonderful, because you just keep smashing forward.
01:01:15And, you know, one problem gets solved, and it bears the next one.
01:01:19It exposes the next one, yes.
01:01:21Yeah, you didn't even know that it was going to be a problem, and there it is.
01:01:25We went to disc brakes and then to slick tires, and suddenly steering heads weren't stiff enough.
01:01:32They were tending to tuck under.
01:01:34Fork tubes weren't big enough.
01:01:3635, 37, 39.
01:01:40Now, 50.
01:01:4250.
01:01:43So, that is the result of having to transmit the load of slick tire plus disc brakes
01:01:55to stop a 400-pound thing, well, 500 and something with the rider in fuel, at 1.4 Gs.
01:02:08There was a rumor in 1976, and I never asked him about this, that Gary Nixon had bent a set
01:02:17of fork tubes while braking at Loudoun.
01:02:20I'd like to know if there was any substance to that.
01:02:23Oh, there's the lore about Freddie Spencer bending the handlebars on his Honda Superbike.
01:02:29Yes, and Ben Spees on a MotoGP bike.
01:02:34These fellows don't go to the gym because they're physical culture enthusiasts.
01:02:41They go because it enables them to survive the conditions in which they work.
01:02:52So, it's like the swing arm, which has had to increase its ability to transmit force with every change, tires,
01:03:03brakes, etc.
01:03:05The humans have to have something done for them, and that something in the current moment is electronic rider aids.
01:03:17It's 130 miles per hour at the island.
01:03:21I was at Worlds.
01:03:23Yeah, I rode around the island on a Honda cross tour thing, you know, one of their V4 sort of
01:03:30street adventure bikes.
01:03:32And just as the course was closing, riding around, I was led by Freddie Dew, who's the son of David
01:03:40Dew, who does the press for the TT.
01:03:43And he says, okay, we're going to ride the course as they close it.
01:03:47I'm like, great.
01:03:48So, we arranged, we got some Hondas out of some, you know, like European Honda stuff out of some garage
01:03:54down in Douglas and went down and got it and hauled away.
01:03:58And we were riding the course.
01:04:00It was, I was going at 75, 85 miles an hour.
01:04:06And I'm thinking, like, how do you set a bike up for this?
01:04:09Because it was just bumpy in a section where I have no idea how fast she'd be going.
01:04:13Probably like 175, something like that.
01:04:16Just a big, long, straight piece of road.
01:04:18It was shocking.
01:04:20I just, I can't imagine what those guys are doing and going through and the repeatability that they demonstrate.
01:04:29I was thinking about the swing arm and an instance at Laguna Seca.
01:04:34It was Aaron Yates and Doug Chandler, Muzzy Kawasaki.
01:04:39And it was a press conference and both those guys were in it and we were asking questions.
01:04:43And I had gone to Muzzy's tent, you know, the big rig.
01:04:49And I was looking at the bikes and Doug Chandler's bike had a beautiful built-up swing arm.
01:04:55A lot of vertical section, narrow sides.
01:04:59I mean, it was, it was a piece of art.
01:05:01And I looked at Aaron Yates' bike and I was like, huh, street bike, you know, like very, very basic.
01:05:07And so I asked, I didn't, I didn't make note of that really in the question, but I just asked
01:05:11Doug.
01:05:12I'm like, hey, that swing arm, you know, can you tell me a little bit about that swing arm?
01:05:15And Aaron Yates is like, and Doug's like, oh, well, you know, we got a kid arm and, you know,
01:05:21we're just trying something out, as you always say.
01:05:24And then Aaron Yates is over there and he leans into the mic and he says, I would like to
01:05:27point out that I do not have that swing arm.
01:05:31Wonderful.
01:05:32So if you don't think it's important, it is.
01:05:35Another swing arm story is talking to someone who was inside the Kawasaki race team.
01:05:41And at the time, you know, we were well past the prototype stage where everything was custom and made of
01:05:48titanium and all that.
01:05:50But, um, but he said, any more, if there's a piece of a motocross bike that you want to, um,
01:05:56that you would like to claim that you'd like to get your hands on, it's the swing arm.
01:06:00He said so much work goes into the swing arm of these guys at the pro level to really make
01:06:06them do what they need them to do and to make them have the feel and the traction and lateral
01:06:10stiffness and all that stuff.
01:06:11It's, it's great.
01:06:13It's nice that the whole thing is, as ever, as we always observe, the whole thing is a, is an
01:06:19interactive system.
01:06:20Everything relies on everything else.
01:06:21And you change one thing and you're going to have cascades of problems that you never foresaw or solutions, or
01:06:28that one thing becomes the solution.
01:06:30Like you were talking about, uh, in another podcast, well, we're just going to put a longer swing arm on
01:06:35it, but then, well, wait a minute, I can't get off.
01:06:38It's spinning.
01:06:39Why, what is this?
01:06:40You know, we're not getting those, the weight transfer podcast.
01:06:44And, um, sometimes it is a solution.
01:06:46Sometimes that one thing is a solution.
01:06:48If you want to race a Yamaha XS650 and you want to use a stock frame, you use the later
01:06:53chassis and you get a longer swing arm and it tends to balance it out.
01:06:58It works.
01:06:59It is that sort of one solution, but at the level of race bikes or MotoGP at this point, imagine
01:07:05that, like, imagine someone suggesting that,
01:07:08well, let's put a one inch longer swing arm on your bike there, Valentino, or whatever, you know, maybe.
01:07:15What year was it that Cycle World ran that, uh, uh, Richard Stamboli built Yamaha in the 200 and you
01:07:22had to change the swing arm to a stock one at the last moment?
01:07:27Um, well, that would have been circa 2000-ish.
01:07:34It might've been just before I got on.
01:07:36Um, might've been just after, but I remember we were racing the stock Yamaha, um, in Supersport.
01:07:44There was one, we were racing a stock Yamaha in Supersport and it had, we did everything stock, like it
01:07:49had turn signals.
01:07:51And then the art department made a license plate that looked like a California plate that read Stocker.
01:07:56And then the license plate frame said, what's your excuse?
01:07:59So if we passed anybody, that's, that was the message they were going to get.
01:08:03The message, yes.
01:08:04Yeah, because there were 40, you know, 40 or 50 bikes on the grid.
01:08:07The bike with the, that had to have the standard swing arm put in it at the last moment, weaved
01:08:14for 200 miles, just steady.
01:08:19Because it wasn't stiff enough.
01:08:22Yeah, we had a 94, uh, that we raced at Laguna Seca that Richard built.
01:08:27And so it would probably would have been circa around that time, YZF 750.
01:08:31Yeah.
01:08:32Yeah.
01:08:35Remarkable.
01:08:36Well, that's a swing arm, folks.
01:08:38There's probably more to say.
01:08:39There always is.
01:08:40Ah, yes, indeed.
01:08:42Um.
01:08:45We're not the foot down the wall, but we do have some stories.
01:08:49Yeah.
01:08:49And, uh, just as performance keeps evolving, uh, ahead of us, we keep chasing after it, trying to understand everything
01:08:58that we can.
01:08:59And we appreciate all those people in the paddock who are always digging in.
01:09:02And sharing information now and sharing photos, unknowingly sharing crashed bike photos that have in MotoGP sand traps where you
01:09:12can see mass dampers that are hidden under body work.
01:09:15But now I've been cracked open like an egg to reveal the contents.
01:09:20So that's, that's a tip, folks.
01:09:21You know, if you're going to drop your $180 on your MotoGP video subscription, watch it on a big screen
01:09:28and freeze those frames during crashes and look for stuff.
01:09:33Send it to us.
01:09:35Once again, join us, uh, join us every week.
01:09:38Thanks for being here.
01:09:39Uh, check us out on Patreon.
01:09:40The link is in the description.
01:09:42Um, hope you like that too.
01:09:44And like I said, we're going to, we're going to throw some, uh, extra content there.
01:09:48I'm going to convince or force Kevin to give us a tour of his shop and show us the U
01:09:52-boat, uh, submarine lathe that he got and his welder.
01:09:56Unfortunately, the 4360s are gone, but I have a vintage video that I shot vintage.
01:10:01It's vintage now, Kevin.
01:10:02And I shot around 2006 on a grainy old, probably Sony camera, uh, with like eight pixels or something, but
01:10:10I walked around your shop and did a tour is when I came out to do the RD motor with
01:10:15you.
01:10:15And I was like, Hey, check this out.
01:10:16And I just walked around and showed a few things and my voice sounds different.
01:10:20My young voice is different than my now voice.
01:10:22I'll call it a now voice.
01:10:24Anyway, see us on Patreon.
01:10:27We'll have some stuff there.
01:10:28In addition, everything without commercials, this podcast included.
01:10:32Thanks for listening.
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