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BIG BANG! How Firing Order Can Change An Engine.
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00:00:00It's the Cycle World Podcast. I'm Mark Hoyer, Editor-in-Chief. I'm with Kevin Cameron, our
00:00:05Technical Editor. This week we're talking about, well, Big Bang Theory, or the bringing
00:00:14of Big Bang to two strokes at first, grouping the firing order together. That's kind of
00:00:20the topic here. Honda found that success with one Mick Doohan on the NSR 500. We'll talk
00:00:28about the grouping of the firing orders and all that. There's also, in dirt track, there's a long
00:00:32history of the Twingle, which is taking a twin and grouping the firings close together. So there's
00:00:39a long period of not firings. 45 degrees between the two firing impulses instead of every other
00:00:51revolution. Yeah. And we'll even throw a little cross-plane four-cylinder Yamaha Action versus
00:00:58V4 in here. But since it's two-stroke Grand Prix racing, it won't be 1865.
00:01:08Go ahead, Kevin. Set us off. Light that fire.
00:01:16I like to emphasize that engineers do not just sit around tapping rhythmically with their
00:01:22pencil tips on the table, which is not stacked with books and notes and reports and broken
00:01:29parts. But it's, yes, instead, they are driven to desperation by problems that constantly arise
00:01:41and it is these problems which force people to try different things in an effort to solve
00:01:51problems. Now, originally, when Honda got back into Grand Prix racing, Freddie Spencer on the
00:02:03three-cylinder, the triple, in 1982 managed to win two races in his first season.
00:02:12Because the bike was small and light and it did not abuse its tires. This was right at the very
00:02:21end of the bias ply tire era. But it was decided that they couldn't get much more than the 128
00:02:33horsepower
00:02:34they had already got from the triple and they needed to use all the cylinders the rules would get them
00:02:40four. So they built NSR 500, which was a V4. As in the case of the triple, they wanted to
00:02:53minimize the
00:02:54number of main bearings. All that friction from rolling element bearings just building up. And so they made
00:03:04a single crankshaft V4. And what the engineering books say is that you should seek the greatest smoothness,
00:03:20the smoother the pulsing of torque from the engine, the less clutch mass you need, the narrower your gears
00:03:30can be, including the primary gears. And it's just a, it's good practice.
00:03:39Unfortunately, there were other circumstances which intruded.
00:03:46We're lowering the shock load, right? That's what you're talking about.
00:03:49You're lowering the shock load.
00:03:51Each time the engine fires, the crankshaft accelerates. And then between firings, it slows down. And a lot of
00:03:59this is taken up by the clutch spring drive or shock absorber, which could be rubber elements or
00:04:05actual helical springs. Usually there's six of them. So
00:04:11this was later to be called the screamer crankshaft because it fired every 90 degrees.
00:04:19And of course, four times 90 is 360 full revolution. And
00:04:27the first year, 1984, they were trying out the idea, we'll put the gas underneath the engine and
00:04:34that'll make our bike really change direction very quickly. How do you know? Well, Elf is trying it
00:04:41in France and they're our partners and actually made it worse because, um, of things that we've
00:04:49discussed on this site previous, previously. Um, but that wasted part of a year. Um, then, uh,
00:05:00Freddie was able to do the incredible and win the 250 and the 500.
00:05:08But Honda were having some trouble with acceleration. And if they tried to boost the torque, it didn't
00:05:17seem to boost the acceleration. And in 87, they reversed the engine rotation, which means that
00:05:26the gyro reaction when you roll the motorcycle rider left, uh, was partly canceled because the engine
00:05:37spinning backwards and the tires, the wheels spinning forward tended to, uh, produce opposite effects with
00:05:43some cancellation. Which is the practice now, right? All the MotoGP bikes have a reverse rotating
00:05:51engine. So it was a good idea. So, um, either that or we humans are just sheep. Sometimes it's hard
00:05:59to
00:06:00tell. So another thing they changed was, um, Yamaha came up with their power valve system, which was
00:06:13eyelids at the top of each exhaust port, which could go up and down to soften,
00:06:21the hit as the engine came on the pipe. When pipe resonance begins, um, you can have the torque and
00:06:29double in just a couple hundred revs. And if you're accelerating off a corner and this happens,
00:06:36no, no, please. We don't want that. And Honda at first had their ATAC system. I won't decode that
00:06:45because I don't remember it, but it was a resonator connected to the header pipe by means of a small
00:06:52motorized valve, which could alter the resonant frequency of the pipes. It's a clever idea.
00:06:58It just didn't work as well as eyelids or gates. So in 87 Honda adopted gates. And
00:07:08then, uh, along comes, uh, 89 and Eddie Lawson is riding the Honda and Irv Kanemoto is his, uh,
00:07:22uh, crew chief. And Eddie wanted heavier flywheels. The engineer said, Oh, maybe you would like to
00:07:32have, uh, the same as heavier flywheels, but electronic. No, I wouldn't have heavier flywheels.
00:07:42And, uh, the chassis seemed a bit flexible. So they doubled the side beams and he would like the
00:07:51engine move forward because the farther forward the engine is, the harder you can accelerate before
00:07:58the front end comes off the ground. Well, the engineers had been trained that it was best
00:08:04practice to keep steer effort to a minimum. And this is street bike stuff. So, uh,
00:08:14uh, Eddie was pretty insistent eventually at mid season, which is when a lot of changes come about,
00:08:23they gave him the more forward engine. So it was really a year of theory versus practice. The
00:08:30engineers espousing, uh, theory and Eddie and Irv Kanemoto being, uh, experienced racers. So
00:08:44uh, he managed to, uh, win the championship that year in 89, but in 88, the balance of power was
00:08:54about to be
00:08:55altered by the arrival of, um, Wayne Rainey and Wayne Rainey, that guy, uh, Wayne Rainey and the YZR 500
00:09:06were, uh, uh, uh, a good combination because as one Yamaha engineer put it, he could ride anything.
00:09:17And in a way, this was a disadvantage because if they gave him something that was terrible,
00:09:24he could go quite fast on it. And if they gave him something that was better, he could go quite
00:09:29fast on it. And, uh, Freddie had this problem as well because these were riders who somehow just
00:09:41naturally melded with the, with the motorbike to get the best out of it.
00:09:47So here comes 1990 and it's going to be a clear contest between Rainey and McDoon,
00:09:55raining on the Yamaha doing on the Honda and doing said they were missing something on the exit.
00:10:04They were pretty good on breaking and it was a year of seconds and a few thirds for the Honda.
00:10:14Uh, and this is not a situation that Honda management like, in fact, they dislike it.
00:10:23And so they're struggling away and the next year comes and, uh, performance was better,
00:10:34but they didn't change cylinders or pipes. They didn't come with new, new equipment all that often.
00:10:43And in the meantime, in the background, something promising came up.
00:10:51Now there have been quite a few, uh,
00:10:55250 two cylinder GP bikes that fire at 180 degrees, but occasionally as for example,
00:11:03in the case of Kawasaki's tandem,
00:11:07they timed them to fire simultaneously and maybe it was a test rider.
00:11:14Maybe it was a somebody looking over the track data,
00:11:19but there seemed to be a connection between the firing order and the lap time.
00:11:27You can't ignore something like that.
00:11:31So a big program was instituted and I was told this was not like you're putting a crankshaft together
00:11:39on the press and you say, well, why don't we just turn this one piece to a different angle and
00:11:45then
00:11:47press it together.
00:11:49This was a fine increments of change looking for the peak effect.
00:11:58Now what had happened of course,
00:12:00was that Yamaha had always fired their four cylinder engines,
00:12:04two cylinders together, then 180 degrees, then the other two.
00:12:10And TZ 750 and the inline, uh, five hundreds.
00:12:17And so if there is a firing order effect, they benefited from a lower, uh, level of it.
00:12:27Honda found Honda engineers and test riders found a,
00:12:32a sweet spot at 67 or 68 degrees.
00:12:38So two cylinders fire, then 67 degrees later, the other two cylinders fire.
00:12:44And then there's 293 degrees of silence.
00:12:52And with this arrangement, they found a big improvement in corner exit grip and acceleration.
00:13:01Now I said to myself at the time, it's the same cylinders producing the same output.
00:13:08What's different.
00:13:09But of course I wasn't thinking.
00:13:13About tires.
00:13:16And of course here, tires are a flexible material that is not 100% elastic.
00:13:27I used to, I used to marvel at the rubber backing on a pad of note paper.
00:13:31It was rubbery, but when I'd strip off a piece and stretch it and let go of it, it went,
00:13:37uh, it recovered its shape slowly.
00:13:43All rubber does this to some extent.
00:13:47There's rubber that's more snappy, like rubber bands.
00:13:52It's ping.
00:13:53What was that?
00:13:54And there's this, this gummy sluggish rubber.
00:13:59Well, uh, when a tire rolls forward,
00:14:05it presses its tread against the pavement texture.
00:14:12As the pressure increases, as the tire rolls on, as the weight comes onto this particular element
00:14:19of footprint, the, at first the, uh, rubber is supported by the, by the peaks or sort of
00:14:28droops or asperides.
00:14:30Asperides.
00:14:31We could call them asperides and, uh, it, it sort of droops in between.
00:14:37And as more pressure is applied, as the tire rolls forward and greater load is, comes on our little
00:14:44bit, the rubber is pressed down into the texture more and more so that the area of true contact
00:14:55increases steadily.
00:14:57And, um, um, this takes time because the rubber has internal friction that makes it sluggish in,
00:15:11uh, expressing its elasticity.
00:15:16Like the backing from that notepad, that was sixth grade.
00:15:20And I sat there doing that and we had spelling, spelling, spelling.
00:15:28Anyway, um, what went on with this big bang firing order is that with the 90 degree crankshaft,
00:15:40the interval between loadings on a given piece of, uh, rubber from the yanking of the chain was, uh, small.
00:15:55So if you're coming off the corner and you've got the tire spinning the regulation 10% or whatever the,
00:16:05the engineering textbooks suggest, um, you're not getting full contact and you're not getting the
00:16:13full effect of the rubber grip.
00:16:16Here's the bottom line, static friction.
00:16:20The, the crate has just been forklifted off the truck and there it sits.
00:16:25We want to set up the new bike.
00:16:28Let's get it in the shop.
00:16:30You push on the crate and it's like pushing on the rock of Gibraltar.
00:16:35So you get a couple of guys and you throw your backs into it and it moves.
00:16:41Come on guys.
00:16:43And you get it moving.
00:16:44And once it's moving, it may only take one or two guys to keep it moving.
00:16:50No, I did it with my mill in the garage, Kevin, 2000 pounds of 54 inch index machine mill made
00:16:56in Michigan, I think.
00:16:58And, uh, got it off the truck and it's on the fairly smooth concrete in my garage.
00:17:02And I'm, I'm trying to push the rock of Gibraltar, not moving.
00:17:06Uh, I got the big heavy duty football looking dude from next door came over.
00:17:12And, uh, once he got it going, it was like a walk in the park.
00:17:16I mean, that guy got it off the line and I, I, we pushed it and it was like, but
00:17:21yeah, get it, get it going.
00:17:22Once it was going and we, luckily we just got it right where it needed to be.
00:17:26Yep.
00:17:28So if, if a rubber tire is pressed into the pavement and has a bit of time, it deforms into
00:17:40much more intimate and larger area of contact with that pavement.
00:17:45But if it's just, uh, passing through, uh, rolling and especially if it's sliding a little bit, it's much harder
00:17:55for it to press down into the texture and establish that larger surface area.
00:18:01And the molecular attraction, which does exist between rubber chemistry and the chemistry of the track surface.
00:18:11So what was accomplished by providing that long dead period between this cluster of cylinder firings was that the rubber
00:18:23could kind of go, oh, that feels better.
00:18:26I'm, I'm, I'm, I'm going to suck a settle in here a little bit.
00:18:30And, uh, it was able to get back to something more like static friction.
00:18:38And for the sliding frictions to die away.
00:18:44And, well, that's a very good story.
00:18:47I have no proof other than the lap times because in 92.
00:18:54Doohan won the first four GPs and he won five out of the first seven.
00:19:02Then he had his accident and he was out.
00:19:06Now, the first word of this invention to get out seems to be a mysterious person who phoned someone.
00:19:18Maybe this was Malaysia.
00:19:21Maybe there's an office somewhere in the windows open.
00:19:23It's warm in Malaysia.
00:19:25And the connection is established.
00:19:28And immediately the caller hears this strange sound.
00:19:32Is this road racing or is this 500 motocross?
00:19:37Because what he heard was a deep grunty sound.
00:19:43Instead of the shriek, he expected.
00:19:49And that was, that was the first, uh, outside news of this phenomenon.
00:19:55And of course, as soon as the GPs began, it was clear that Honda had this tremendous advantage.
00:20:01And, uh, he was injured, uh, mid, mid season.
00:20:07And, uh, when the next, uh, when the next season began, uh, Rainey was badly hurt and, uh, which was
00:20:19a career ending thing.
00:20:24And, uh, Kevin Schwartz on the Suzuki, which had pretty strong acceleration and line holding capability by that time, he
00:20:36became champion.
00:20:38But then came the next year, Mick Doohan restored on the Big Bang Honda.
00:20:46And it was a rain of five uninterrupted sequential world championships for him.
00:20:54Um, and, of course.
00:20:58Which you could argue that is very good racing.
00:21:01Yeah, sure.
00:21:04Um, from whose perspective?
00:21:06Yeah.
00:21:06By the ninth race, um, Yamaha were ready with a quickie.
00:21:12They clustered their two fire simultaneous firings, 90 degrees apart.
00:21:20Um, but the effect was there.
00:21:23Help, helpful effect.
00:21:25And doing one, five championships in a row.
00:21:30So, well, when Yamaha brought their, um, quickie to the first race, I think two of four bikes broke their
00:21:41primary gears.
00:21:43And, uh, there was probably clutch slip.
00:21:48And it could be that, uh, gears in the gearbox were showing signs of nibbling little teeth, tooth, uh, pitch
00:22:00line pitting.
00:22:03So, there were a lot of changes that had to go on with, to support this invention.
00:22:09And on the bikes that, um, adopted this firing order, production bikes, uh, these changes had to be made.
00:22:19The R1 also needed a balance shaft, of course.
00:22:23And it became part of our, uh, our culture to say Big Bang when talking about close firing order.
00:22:33But there are other effects on traction or on the rider's perception.
00:22:39That are equally interesting.
00:22:43There came a time, um, when Yamaha's, which in the four-stroke era, beginning in 2002, were running inline fours,
00:22:57transverse mounted inline fours, like the classic Jalera.
00:23:01And Honda were running V4s.
00:23:06And the V4s seemed to be able to accelerate a bit harder than the inlines.
00:23:15And for a time, they simply were, well, it's a new series.
00:23:20We're racing four-strokes instead of two-strokes.
00:23:23It'll take us a while to learn the ropes.
00:23:25But then it sort of became clear, hmm, we have a, we have a problem, Houston.
00:23:35So, whom do they put on this problem?
00:23:38But their master of noise, vibration, and harshness.
00:23:45Masao Furusawa.
00:23:48He had previously, um, smoothed out the RD-400.
00:23:56And he had also caused the snowmobile division to sell more sleds by putting a rational front end on the
00:24:08Yamaha sleds.
00:24:12So, he was put in charge of the team.
00:24:16If you have ever turned a four-cylinder inline with a flat crankshaft, that is one that has two pistons
00:24:24up and two pistons down,
00:24:27you will notice that it's very easy to turn it near top and bottom center, but harder to turn in
00:24:35between.
00:24:36Because twice per revolution, all the pistons stop completely and must be re-accelerated.
00:24:46On a racing engine, that means that a mass of a pound or two is having to be brought to
00:24:53a stop and then re-accelerated to 100 miles an hour, more or less.
00:25:00What does that do down the line?
00:25:04It's transmitted through the gearbox and the chain, um, fairly undiminished to the rear tire.
00:25:12And Mr. Furusawa said, I don't know which it is.
00:25:18Does that, uh, variation in torque as the pistons must be started and stopped interfere with tire traction?
00:25:28Or does it interfere with the rider's ability to detect the maximum with the throttle?
00:25:36He was being, um, formally correct in not claiming to know what he didn't know, which was it, but it
00:25:48brought them parity with the V4s.
00:25:52Uh, Valentino Rossi was able with a lot of modifications and desperate changes to, uh, win the 2004, uh, world
00:26:04championship.
00:26:05In MotoGP.
00:26:09So, um, a few years later, they switched the production R1 to this firing order.
00:26:15And that's why they have that fascinating rhythm, that V8 sound that they make.
00:26:23And I think that is good, is reason enough for a manufacturer to adopt a cross-plane, that's what Yamaha
00:26:34called it, cross-plane crankshaft, because it takes away the monotonous, even-firing drone of the inline four with a
00:26:45flat crank and replaces it with a much more interesting syncopated sound.
00:26:52Now, it can be argued that, and Phil Irving, who was always on the scene at Vinson, Phil Irving speculated
00:27:05about a 270 degree phasing for twins, that this might produce a useful effect.
00:27:14The effect, the effect is useful, but what it turned out to be for our industry, our industry.
00:27:22Industry.
00:27:23For motorcycling.
00:27:25What turned out was, it gave it a fascinating Ducati-like sound instead of a droning 1965 Triumph sound.
00:27:35Euphony.
00:27:37Euphonious.
00:27:38Euphonious.
00:27:38It was euphonious.
00:27:42So.
00:27:43Yeah, people seem to like it.
00:27:44They're all 270s now.
00:27:46Yes.
00:27:47Can't find it.
00:27:47Triumph introduced, reintroduced the Triumph Bonneville in 01.
00:27:53And what did they do?
00:27:54They put a 360 crank on it, because they just had to.
00:27:57Yeah.
00:27:57And then they threw a 270 at it, and everybody liked the 270, and they don't do a 360 anymore.
00:28:03Yeah.
00:28:04And you name it.
00:28:05All the other parallel twins out there, everybody's running the 270.
00:28:08And even the old XS650 guys, it's harder to do a 270.
00:28:13I think you can easily rephase the crank.
00:28:16I mean, relatively easily rephase an XS650 crank to 277, and a lot of folks do that.
00:28:22Of course, you've got to change your camshafts and all that.
00:28:24Oh, yeah.
00:28:25Yeah.
00:28:25But we humans do a lot to be different, not necessarily with any benefit other than sort
00:28:35of an inward pleasure, and there's much to recommend that.
00:28:39So, this is another case of, does the production R1 have a cross-plane crankshaft because it
00:28:52sounds good?
00:28:53I think it sounds good.
00:28:55Or because there are so many riders who are saying, all those guys on V4s are getting
00:29:00away from me off the corners.
00:29:09So, this kind of thing is marvelous because it shows that there is an overlap between sort
00:29:21of abstract human preferences.
00:29:23I just like it.
00:29:25I just like it.
00:29:26That's all.
00:29:26I don't know.
00:29:27I don't have to know why.
00:29:29And some solid engineering reason.
00:29:32Click went to stopwatch.
00:29:34Much better, said the engineer.
00:29:41So, we could have studied all this with putting playing cards in the spokes of our bicycles,
00:29:46I suppose.
00:29:47But what it took was that tedious narrative that I gave you before we got to the heart
00:29:54of the matter, static versus sliding friction.
00:29:57They had to build up a tremendous need to improve their off-corner acceleration so that
00:30:06they would actually throw resources behind it and come up with something.
00:30:12And they came up with what was a surprise to the road race people, but on dirt track, everybody
00:30:18knew about it all along because of this twingle effect.
00:30:22And twingles, aren't they banned currently?
00:30:27That I don't know.
00:30:28The rule book just came out for AFT this year.
00:30:30I haven't read it yet.
00:30:34So, of course, the people making rules are always giving the wrong reason for making them.
00:30:40They're going to save teams all this money, but they haven't done anything about the major
00:30:48costs, which are transportation and personnel, hotel, and all the rest of it.
00:30:57Well, we are cost centers when you get down to it, Kevin.
00:31:01People are just cost centers.
00:31:03That's it.
00:31:06It's just one of those things that – oh, and at one point, I asked Robin Tullui, who
00:31:15built the – what was that snowmobile engine-powered thing?
00:31:19Oh, the Tularis.
00:31:20Yes, I almost said Tularemia, but that's wrong.
00:31:24Rabbits catch that.
00:31:26But it was a remarkable, very lightweight, very fast accelerator and two-stroke motorcycle.
00:31:34And I asked Robin, who went – he spent years and years in Formula One and finally set up
00:31:44on his own somewhere saying that he'd lost interest.
00:31:50But if anyone could, it would be him because he can light up any discussion with his mathematical
00:32:00understanding of physical phenomena.
00:32:04And I said, why hasn't this effect occurred in Formula One?
00:32:10Because, he said, they're shaft drive.
00:32:12Those shafts have a lot of torsional give in them.
00:32:15They couldn't transmit those sharp torque pulses.
00:32:22That was a conversation that took place in front of the flat nose of some great big transport
00:32:29truck in the Valencia paddock.
00:32:33Oh, there's Robin Tullui.
00:32:36I'll go waste his time.
00:32:38Anyway, this kind of thing shows that the more closely you look or the closer the competition,
00:32:49the more abstruse may be the differences that you discover and the potentialities of benefit.
00:33:01So, motorcycles have gotten pretty good, but people have been saying that they have gone
00:33:09beyond human capability since the 1920s.
00:33:15I don't remember what the lap record at the Isle of Man was in, say, 1925, but now it's
00:33:23over 130 miles an hour, and I think in the early days it was like 47 miles an hour.
00:33:31Yes.
00:33:32Well, it's a big shift.
00:33:34I'd say new Ducatis, new M1000RR BMWs are definitely a new era for street legal performance.
00:33:44It's just mind-blowingly capable, fast, traction control, you name it.
00:33:52And the tires, of course, have come along with it.
00:33:55So when you get a slick tire, especially, but man, it is, you have to respect all of those
00:34:02guys, your McDoins, Mark Marquez's, Valentino Rossi's, the guys who especially make it look
00:34:09so effortless, but, you know, your Max Biagi, he was instrumented with a heart rate monitor,
00:34:16and Max was over 200 beats per minute from his heart rate during a race.
00:34:21Now, he was-
00:34:22Like a cute little rabbit.
00:34:23He was a more keyed up kind of, if you've ever met Max Biagi during his racing years,
00:34:30he was a more tense person than, say, your Valentino Rossi, and Rossi was more like 180,
00:34:35as I recall.
00:34:36There was a German, I think, who had-
00:34:38And Eddie Lawson also was, it was, 180 was attributed to him.
00:34:44Yeah, and so you have, maybe there's, you know, the psychology at work there where you're
00:34:49not, I don't know, the, it's not, Max Biagi has to be intellectual.
00:34:55I was going to say, well, it's the intellect at work and the intellect being able to understand
00:35:00and process all that information, but obviously Max had that capability as well.
00:35:03He just had a different angle coming at it.
00:35:07But that's, high speed can be really terrifying.
00:35:12And this is not a Max question, but it's putting someone who's not experienced on a motorcycle
00:35:17versus someone who is, and barreling toward a corner knowing, oh yeah, the bike's going
00:35:23to stop.
00:35:24This is my brake marker.
00:35:26I know I can stop the bike here and have reserve versus not knowing that.
00:35:30And most people, like if you get into a high performance car and you go hauling ass toward
00:35:35a stop sign and you say, you tell me the latest that you think I can stop the vehicle before
00:35:41we get to that stop sign.
00:35:43And they will tell you, and you will stop many, many, many feet before the stop sign.
00:35:50Because if they're not, if they've never trained on that.
00:35:53Anyway, heart rate's interesting.
00:35:55Staying intellectual, being able to pilot the motorcycle at high speed.
00:36:00We hear a lot about, even today, about wanting to tear out the electronics and that it is unfair
00:36:13and contrary to the spirit of motorcycling for the rider to be assisted by electronic rider
00:36:21aides.
00:36:22And I would suggest that those skeptics should buy or otherwise acquire one of these rider aides
00:36:36loaded ultra fast motorcycles and see if they can get around Loudoun on it faster than the
00:36:45local madman on his 800 twin.
00:36:52Because the guy on the 800 twin knows his bike well.
00:36:56He knows how to ride it.
00:37:00He's good at it.
00:37:02And the let's buy it and try it guy, the pay as you go thrill seeker, is going to be
00:37:08horribly
00:37:09disappointed because the local madman is just going to pass you in every corner.
00:37:16And then you can go blaring past him down the next straightaway only to confront panic at
00:37:27the next corner.
00:37:29And here he comes passing again.
00:37:34So I don't buy it.
00:37:36I think that carrier pilots need that beam so that they, and they need autothrottle and
00:37:45all the other things that they've been given to increase their chance of A, being above
00:37:52the deck when they hit it.
00:37:55And B.
00:37:56They call it task saturation.
00:37:57Yes, picking up the third wire and that's all they want.
00:38:04They want it to be safer for the pilot and turn something that is at its worth, hideously
00:38:14dangerous into something that most gifted pilots who've graduated from Navy pilot training
00:38:24can do successfully.
00:38:28And of course, the chances are that the assist that these people receive in aviation is essential
00:38:38to the basic performance.
00:38:40For example, stability control.
00:38:45It's been described to me as modern fighters are like an arrow that's flying backwards.
00:38:52If you cause a yaw or a pitch motion, they will immediately start to flip in whatever direction
00:39:03at a fantastic speed.
00:39:06That's what you want for the best maneuverability.
00:39:10But a human isn't fast enough to manage it.
00:39:14So there's auto-stability built into those aircraft to keep them, to keep the tail feathers of the
00:39:22arrow pointed first.
00:39:25I was talking to a friend of mine who's a warbird pilot and a studier of aircraft.
00:39:30He works in, in aircraft, restoring aircraft and OV-10 Broncos and B-25s.
00:39:39His brother is an engineer at Boeing and we were talking about those systems and the capabilities
00:39:46that we don't see of modern aircraft that the fighters, they don't demonstrate at air shows.
00:39:52They give you a little taste of the full capabilities, but they don't tell you what the full capabilities
00:39:57are.
00:39:58And it's, you know, the rumors are how mind bending the planes, you know, the agility and
00:40:04the things that they can push the plane around and do in the sky as they were damaged.
00:40:09Like, you know, in, in the latest, uh, Top Gun Maverick movie, there was that period where,
00:40:14you know, Mav steals the old fighter from the base, from the country of no name and manages
00:40:21to get it off the ground.
00:40:23And, and then he's having a dog fight with this, you know, latest generation foreign fighter.
00:40:31And it does something crazy on the screen where it does this big rotation and it starts going
00:40:35the other direction.
00:40:37You watch the planes, even at the air show, you watch them fly backward.
00:40:41And we were like, well, you know, what's, what's keeping us from just autonomous flight,
00:40:45like just programming something and going it off.
00:40:47And it was nice to have this engineer and the brothers say like, because the human element
00:40:51is the creative element in all of those systems.
00:40:55And that's true on a MotoGP bike that the rider is the creative element and they're using
00:41:00that tool and they're getting a feeling from the tool.
00:41:02And those, you know, the human psychology and the talent and the muscle memory is evolving
00:41:09with the complimentary equipment and those things together are moving forward and we're
00:41:14getting what we get now, which is incredible lap times and G loading that mere mortals can't
00:41:23stand and couldn't.
00:41:24I mean, yeah.
00:41:27Wayne, Wayne Rainey described, uh, one of his rides against doing in that formative period
00:41:33before the, the big bang saying that, uh, at first I thought he was getting away from
00:41:42me and then I saw that I wasn't falling back anymore and I studied to see what was causing
00:41:51it.
00:41:52He was, um, pushing the front.
00:41:55So I decided to show him my front wheel, uh, regularly because a, I could, and because
00:42:05B, it might increase his push as well.
00:42:10And that's how it turned out.
00:42:15Um, you have to factor in your understanding of the other person against whom you're competing.
00:42:22What is this person?
00:42:24What does this person usually do under these circumstances?
00:42:27Does he, is he known for bad surprises or is he sort of dull as flat and devising where
00:42:38on the racetrack to make a pass attempt considering a great number of variables and this, this kind
00:42:46of thing, uh, simply doesn't appear in, um, what would I call it?
00:42:55Uh, popular video and the, the, the voiceovers of the announcers whom I think of as professional
00:43:07blokes because they have to sound like they're in a pub.
00:43:13They're all having a good time and they're saying the expected thing.
00:43:19And I bought a year, you know, one of those GP season or moto GP season summaries.
00:43:26And I just, I just put it away because the commentary was just, I like to see the bikes
00:43:36though.
00:43:37Yeah.
00:43:37Well, you know, there's that NASCAR joke about he loves, loves to win and hates to lose.
00:43:42So it's all our motivation.
00:43:45We just love winning and hate losing.
00:43:47So we're going to go out there and just be more brave.
00:43:51Or more clever.
00:43:53Yeah.
00:43:53I think, well, of course it's more clever.
00:43:55The, the supernatural observation powers of, and the memory of world-class racers is, is profound.
00:44:04You know, like I go out and I race vintage bikes and I feel proud of sort of attacking
00:44:09the track, learning the track and racing the track so that I can operate the bike at
00:44:15a margin, feel safe and get a lap time.
00:44:18And I can see that I'm competitive without racing against anyone in qualifying or practice
00:44:23that you just go out and ride the track until you have a time that you say, okay, now I'm,
00:44:29that's a race winning lap.
00:44:30That's a race winning lap time where it's a mo it's, you know, okay, I have this, but
00:44:35then when you race, everybody's rushing to the same point.
00:44:39Like we're all rushing to the same point where it clumped together.
00:44:42It's not practice.
00:44:43And then you have to start figuring out what the other bikes on the track are like, and
00:44:47what are they doing?
00:44:48And, you know, we're both seven fifties, but obviously that bike makes more power, but
00:44:55I think I can go faster through corners than that bike.
00:44:59And then you have one corner in particular, which might be a place to make your pass.
00:45:04Yeah.
00:45:05So it's, I was thinking of the BMW versus the XR, uh, TT, the seven 50, the team of sleet
00:45:12seven 50 written by a great rider, but a big heavy bike.
00:45:18And I was on a light bike and if I went in, so then barber, there's two left, right combos,
00:45:24you know, that are blind over a crest kind of a thing.
00:45:26And the BMW was great because the rotation of the crank helped it roll right for the exit.
00:45:32So it was very easy.
00:45:34And I made a, I made a mistake for four, maybe four consecutive laps of going into the chicane
00:45:42at the same speed as the XR and getting out accelerated.
00:45:47And I couldn't pass them by the next braking zone or even on the brakes.
00:45:54So I had to fall back and use the timing to get, get past.
00:45:59And that's a, you know, that's my level.
00:46:01And I think about what, what Wayne, Wayne Rainey is observing, oh, he's pushing the front.
00:46:06And then he's just like, poke, poke, he's just sticking it in, poking in just here and there.
00:46:13Like, oh yeah, I'll just put it there.
00:46:15So he knows.
00:46:17And, and you're going against world-class, you know, intellects and physical beings.
00:46:23It's great.
00:46:24That's why we love racing.
00:46:25Yeah.
00:46:26And of course you're using, uh, the same process that they use.
00:46:31You haven't developed it, uh, to the level that they have, but it's just like racing an RD back in
00:46:40the day.
00:46:40You could have that experience of, of sliding the front tire on occasion that you've seen in those videos or
00:46:50at the races and, um, all for, uh, 500 bucks.
00:46:57No team transporter, no mechanics to pay, uh, no PR people tugging at your sleeve, 500 bucks and you're sliding.
00:47:08Yeah.
00:47:08Whenever I talk about racing or racing advice, my caveat is always, you know, my, like my most recent experience.
00:47:17I can give someone racing advice and I will say, well, you know, keeping in mind that my level of
00:47:24talent and experience could win a bears race in Arma.
00:47:28So that's what you're, that's what, that's what you're getting is I have this much.
00:47:36And, you know, actually Nick Einach used to say that because Nick, Nick finished second in the two 50 Grand
00:47:42Prix championship.
00:47:44And so that's what he would say.
00:47:46He would say like he would, he's running the school, right?
00:47:48He's giving people advice and he's talking to racers and he would, he would just caveat that and say like
00:47:54my advice at, at the most can get you the second place in two 50 Grand Prix championship, national championship.
00:48:03That's where the message is coming from.
00:48:04And that's what you, you know, I mean, we're all, we're all variable, but I think observation, watching other riders,
00:48:11knowing the feelings of the bike, knowing I was thinking about traction spinning versus moderate hookup and drive.
00:48:19And those experiences on slick dirt roads, flat, flat corners, but also on street bikes where a moderate amount of
00:48:31slip and you have drive, but when it actually lets go, it's almost like going backwards.
00:48:39The, the, the, the, the decline in acceleration is huge when it starts to really spin and you're not getting
00:48:48drive.
00:48:49It's a very interesting feeling.
00:48:51And I think that feeling is what you were talking about, about the tire being able to deform.
00:48:56And once it's really spinning, it's just, it's on the, it's on the asperity.
00:49:01It's like a bunch of pencil points, right?
00:49:03All lined up and it's just going.
00:49:07So one riders contribute different things.
00:49:12One of the things that Valentino Rossi was famous for was springing surprises on people.
00:49:19He made impossible looking passes that just caused people to gasp and then shout with delight.
00:49:29But on the motorcycle, he didn't look all that different from Mike Halewood.
00:49:34But along comes Mark Marquez and once he got the feel of those Bridgestone slicks, he was moving his whole
00:49:50torso, not just swinging his butt to the inside in the turn,
00:49:54moving his whole torso inward so that his outside arm was stretched tight across the tank and his inside arm
00:50:06needed an elbow protector because the track was right there.
00:50:12And he had fabulous tire management understanding.
00:50:23And not only that, he could do things that most people would never even attempt.
00:50:30And I don't know whether I should call it uncrashing, but that's what it looks like in the videos that
00:50:37he's down.
00:50:39And then he seems to give a mighty yank and it digs the front tire in and the bike flops
00:50:45back up onto its wheels, gives a mighty shake.
00:50:51And off he goes.
00:50:53Uncrash.
00:50:53Of course, you lose time doing that.
00:50:56So preferably if you're going to do it in practice.
00:51:00But he had found that occasionally he could uncrash.
00:51:08So I don't think that any rider has mystic ability, but it may take time to discover what it is
00:51:16that they're doing.
00:51:17And in many circumstances, like, for instance, Kenny Roberts discovering that on pavement, you could do the same things that
00:51:26he had learned to do on dirt.
00:51:29And understanding that a motorcycle is worth at cornering and best at accelerating because it's just two wheels.
00:51:41And an engine and a place to sit.
00:51:45So instead of trying to, oh, oh, I'm teetering.
00:51:49I'm teetering on the very edge of, oh, I lost it.
00:51:53He was charging into a turning point.
00:51:58Getting the bike going slow enough that he could pretty much get it mostly turned there and then just accelerating,
00:52:05which the motorcycle does well.
00:52:08To a higher exit speed than he would have had if he'd done the great circle route, which, remember, travels
00:52:15farther.
00:52:19And the British press was full of talk about how, oh, we all have to go dirt track racing now
00:52:25so we can be like Kenny.
00:52:26And riders have different things to contribute.
00:52:34Freddie Spencer learned to recover the front when it was gone.
00:52:43And wonderful stuff.
00:52:46He described, he said, there are two dirt tracks down there in Kentucky.
00:52:50He said, I used to kind of play with it because they were more shaped like a football than they
00:52:55were like the Indianapolis 500.
00:52:59And he said, if the front started to go, when I would normally have said, well, that's it.
00:53:10Hope I don't get hurt.
00:53:12He said, a whiff of throttle would reduce the load on the front often just enough that it gripped.
00:53:22And he went around the corner and Irv Kanemoto told about seeing Randy Momoa watching this.
00:53:30And he said, I don't think he ever understood it.
00:53:34At least not then.
00:53:37But these are things that riders create by having a close symbiosis with the motorcycle and finding new ways to
00:53:52exploit that, often brought about by something new, like, for example, the Bridgestone front tire.
00:54:05I asked two different riders.
00:54:07One was Mark Marquez, when he would just come into MotoGP, and the other was a super veteran, Colin Edwards
00:54:15Jr.
00:54:16They both described that front tire in the same, practically in the same words.
00:54:21You can just keep loading it and loading it, and it doesn't give up.
00:54:27Normally, the curve relating the load on a tire to the grip it has goes up linearly at a slope,
00:54:37and then it softens as the grip starts to fall behind the load.
00:54:42And then it heads on over and decreases.
00:54:47What they were describing was, and the softening occurs after the rubber has been pushed into every pore of the
00:54:55pavement, and now it's like a mooly grater.
00:54:58It is the tear resistance of the rubber that is providing the grip.
00:55:07But when the tear resistance is fairly low, it just shaves rubber off the tire, and you lose the front,
00:55:16and you're down, inspecting the pebbles.
00:55:21And so the Bridgestones were part of the silica revolution, and I suspect that if we could see that curve
00:55:35for a Bridgestone, that it just kept on the upward slope to a higher level.
00:55:42Well, Michelin, for whatever reason, we don't have access to their thinking on this point, but more often than not,
00:55:52Michelins have excellent rear tires and so-so fronts.
00:55:59And with Bridgestone, it was the other way around.
00:56:01They had mysteriously wonderful front tires and, you know, rear tires.
00:56:08It's back there.
00:56:11Yeah, I was once at dinner with Cal Carruthers.
00:56:14I was at Paul's house, Paul Carruthers' son, who was my boss at Cycle News.
00:56:21We had a barbecue, and Jim Allen was over.
00:56:24Jim Allen was the American racing Dunlop guy, so he was the guy who went to all the MA Nationals
00:56:29and the famous story.
00:56:32I just happened to be there, but Nicky Hayden got his first qualifying tires.
00:56:37It was at Laguna Seca, and I happened to be walking through the pit.
00:56:41They gave Nicky qualifiers.
00:56:44He went out.
00:56:47He had a pretty good lap time.
00:56:48He came back in, and he was walking toward Jim Allen, and you could see his face was like, you
00:56:56know, Nicky's face.
00:56:57And Jim's like, let me guess.
00:56:59By the time you figured out how good it was, it was gone.
00:57:04He said, yeah.
00:57:06And those tires, those cues, man, you could just turn it open.
00:57:10You could just completely let it go, and the bike would drive, and he was doing the right thing.
00:57:16He was feeding more and more, and then he was like, oh, my.
00:57:20And then the tire, because they don't last long, they're qualifiers.
00:57:23They give all very quickly.
00:57:26It was just fascinating.
00:57:27They said to riders, as little as one lap, and they've replied, if that.
00:57:34Wow.
00:57:37All this discussion reminds me of, you know, rider aids.
00:57:41We talked about rider aids.
00:57:43I've talked to a few riders who say, this is years old now, but they would work on the mechanical
00:57:51grip.
00:57:51They would ride the bike without a lot of TC or any TC, and they would work on making the
00:57:58bike work without that stuff,
00:58:00and then adding in electronics, getting the mechanical grip.
00:58:05And it makes me think back to McDoin riding a screamer and then switching to Big Bang and getting better
00:58:13drive.
00:58:15You're allowing McDoin to have a better management of tire slip with his natural abilities.
00:58:27So then I think, well, what would McDoin have wanted?
00:58:31Probably to have TC on that 500.
00:58:35Yeah.
00:58:36And then you might be getting into the virtual power band, as we've discussed, where now they're cranking up outputs
00:58:44to get this astronomical amount of power,
00:58:47and they're managing the fluttering of the butterflies to smooth the torque curve out somehow to make, you know, to
00:58:54make drive happen and to make the torque re-estab workable for the rider.
00:58:58Well, if the natural, one type, one very common type of natural power curve has a dip in it,
00:59:05and the dip is caused by the interaction between waves in the exhaust pipe and the valve overlap.
00:59:14But there's also a point in RPM where that effect works against you.
00:59:20Instead of putting fresh charge into the cylinder, starting the intake stroke early with that before the piston has moved,
00:59:28it's pumping exhaust gas into the combustion chamber.
00:59:32That's the dip.
00:59:34And below that is where the curve would have been normal, so you get this shape.
00:59:39So what a virtual power band does is when you're accelerating out of a turn and you don't want to
00:59:46get caught in the dip or be surprised by the sudden moonshot from the bottom of the dip up to
00:59:54peak torque,
00:59:56the butterflies are opening to fill in the dip, and then they're closing to restore the torque to what you've
01:00:06asked for with your throttle angle so that it's as though the engine doesn't have that dip.
01:00:12It's as though it's been filled in, not with body filler, but with butterfly movement.
01:00:18And obviously this can't work if you're on full throttle, but these bikes are on full throttle a very small
01:00:27percentage of the time.
01:00:29How are you going to imagine 300 horsepower in your street bike?
01:00:38Or because your street bike is heavier than a MotoGP bike, 500 horsepower.
01:00:44Are you going to manage it?
01:00:46Would you like to rip out the electronics?
01:00:48The classic example is the 1998 Yamaha YZF-R1.
01:00:53It was lighter.
01:00:55It made 135 horse at the rear wheel, which was astronomical.
01:00:58Like the competing motorcycles were 129 was, I think, where the ZX-9 was, 120, somewhere like that, 127, something
01:01:10like that.
01:01:11So it was like basically 10 more horsepower from the R1.
01:01:14It was significant, like way lighter than the ZX-9.
01:01:18The equivalent Honda CBR 900RR was making 118 at the rear wheel.
01:01:24So you have 135 horsepower bike, but the torque curve was like what you described, the two peaks.
01:01:32And let me tell you, wheelies everywhere because it just came in.
01:01:37Wheels spin.
01:01:38I almost high-sided that motorcycle leaving my neighborhood riding to work because two things.
01:01:45A rapid torque spike and these tires I was using were DOT race tires.
01:01:51They were a Michelin, and man, when they were cold, they were like bowling balls.
01:01:57And I didn't do anything crazy.
01:02:00It was a dry morning.
01:02:01I just turned.
01:02:02I came out of the neighborhood.
01:02:03I dipped it left to get onto the four-lane, you know, big road with people going 65, 70 on
01:02:11it.
01:02:11And I just dipped it, and I just rolled in to accelerate into traffic.
01:02:15Nothing crazy.
01:02:16And that thing went, slid to the lock.
01:02:18It had fixed foot pegs, and I'm wearing jeans because I'm riding to work, and the thing goes click, click,
01:02:24and it whips me.
01:02:25And I did not crash, but that foot peg went into my leg.
01:02:29It went through my pants, ripped my pants, and then cut me because it was fixed, and it had machined
01:02:35edges.
01:02:36They weren't full round with plugs in it.
01:02:38They were machined to look good.
01:02:40And that's why you put plugs in your handlebar ends or your clip-ons, because you don't want to take
01:02:46a core sample out of your body with the clip-on in the worst-case scenario.
01:02:50A core sample.
01:02:51Wonderful.
01:02:51Yeah.
01:02:52But anyway, the 98R1 had that torque curve that you're talking about, and it had no electronics.
01:02:57And it was certainly thrilling, but we've worked to smooth that out.
01:03:02You've remembered the experience.
01:03:05Yes, we want better.
01:03:06Yes, we do.
01:03:07We want better.
01:03:08And boy, we could talk about crank mass, wheel mass, you know.
01:03:14And we will yet, but maybe not today.
01:03:17Not today.
01:03:18But dirt track, you know, looking at dirt track, dirt's just dirt.
01:03:22It doesn't change that much.
01:03:23It's just dirt.
01:03:24That's all we've got to race on.
01:03:25Lap time isn't all that much better than it was in 1911.
01:03:30So, it's fascinating the way that we try to manage that traction and learning to do that, as you have
01:03:38said, with your Kenny Robertses and Freddie Spencers and Valentino Rossi's Ranch, man.
01:03:44There's flat tracking all over.
01:03:46They have road courses and dirt, and those guys go there, and they practice all the time.
01:03:51There goes the front.
01:03:51But, man, it's, you know.
01:03:53Well, I remember the words of Cook Nelson when he had his first interview with Kenny, which was years ago,
01:04:01the 70s.
01:04:02He said, I went to this thing, and I'm thinking, I'm going to go see some quick-risk kid who
01:04:12just gets out there and skids around.
01:04:14But he said, what I found was an intellectual of motorcycle racing.
01:04:20He talked about what he does on the motorcycle, and he explained why it worked.
01:04:28Now, this brings up a fundamental point about motorcycling, and that is that, at its best, it is a high
01:04:38-speed intelligence test.
01:04:40How fast can you recover data?
01:04:43How can you establish a parallel between this situation and something that you've handled?
01:04:50How are you going to combine the agility of your mind with the capability of the machine?
01:05:01Pretty attractive.
01:05:03It is.
01:05:03It's terribly attractive.
01:05:04And it's not just a quick-risk kid getting out there and skidding her around, although there are plenty of
01:05:10those.
01:05:16Yes, I've heard the stories.
01:05:18Unnamed riders.
01:05:20This, you know, a rider X will never win because he doesn't know how to preserve the front tire.
01:05:29I looked at wear marks of an AMA superbike rider, and they looked wrong, front tire wear marks.
01:05:38And I asked Jim Allen about that, and he said, it's because my tires didn't look like that.
01:05:43And he says, it's because the way he's braking, he's braking so hard and combining turning with that,
01:05:49that his wear pattern is going to be completely different than yours because you're just riding around, you know.
01:05:56Yeah, I've seen those front tires that were being used as brakes, scrubbing off speed with the front.
01:06:06And there's times to do that, but like McDoon said on another occasion, you can't do it all day.
01:06:17Excellent.
01:06:18Well, thanks for listening, folks.
01:06:20That's it for Big Bang.
01:06:21As ever, we wandered into other nooks and crannies related to Big Bang.
01:06:26Green pastures.
01:06:27Green pastures, traction, human psychology, high-speed intelligence test, Cook Nelson, Kenny Roberts, you name it.
01:06:35We appreciate you listening.
01:06:36Share this with your friends if you like it.
01:06:40We'd love to talk to them.
01:06:43And we appreciate you being here.
01:06:45See you in the comments.
01:06:45We'll catch you next time.
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