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My response was to Dave and his assumption that gearboxes seems almost bullet proof Please note that I didn't mention the word clutch anywhere as I agree that proper technique will not damage the gearbox - be that with or without use of the clutch. Now to your questions Is there any advantage to doing clutchless downshifts? Advantage? It must be that you can retain a full grip on the left side of the handlebars. I honestly cannot think of any other valid reasons. Shifting down at lower rpm isn't valid - you can do that also with the clutch. What are the pros and cons of clutched and clutchless downshifts? Pros: See above. And your race will not be affected if your clutch release fails (which isn't very often). If you find it easier to perform clutchless shifts than clutched shifts, you will find it a pro as well. I'll risk saying those will be in a great minority if you make a study among all riders in the world - just as you are likely to find among car drivers, whose gearboxes are also simple to shift without the use of a clutch if you take care. Cons: It takes time to master for what I personally consider a miniscule return. And many will never master it, but that could naturally be said for a lot of things. It will make you less likely to pull the clutch should the rear wheel lock up due to a mechanical issue (which, admittedly, doesn't happen very often). It will, in my opinion, increase the number of poor shifts for most riders, increasing the risk of gearbox damage. In conclusion, I will say that both pros and cons are very limited and that it is more down to personal preferences than any real benefits. But please feel free to disagree. My words are no more gospel that those of others. What I can say is that I have tried clutchless downshifts many times over the past 30 years and never found any reason to persue the subject into perfection because for me, the clutch is something I can operate well without thinking about it.

Bent or worn shift forks and damaged dogs/slots on the pinions are, if not exactly common, not unusual. Pre-loading the shifter will put bending forces onto the shift forks - too much, and it can bend permanently. Even restricted pressure will increase wear. However, they can usually take quite a bit of wear before they stop functioning. Bending them, though, will usually make it hard to shift or gears to jump out under load. Bending them do take some serious effort, however, and isn't very common. Having the dogs or "claws" break is perhaps a bit more common damage done to motorcycle trannies and is caused by shock loads. Imperfection during production will make this kind of damage more likely. However, elongated slots or rounded off dogs is by far the most common thing to take place, as they wear over time. The result is that the affected gears starts jumping out under load. Here is a picture of a badly broken pinion Rounded dogs

Doohan, under control Schwantz,probably less so Schwantz, now simply a passenger?

Roberts Jr Rossi Hayden Stoner

Lawson Garnder Rainey Schwantz Doohan Criville

Here are a bunch of pictures from as similar an angle as I could find without spending the rest of my week on the interweb, all from what could arguably be called the modern era, starting out with Ago on his 1975 Yamaha. All these are world champions over the past 35 years and hence the best of their day. For me, it would be interesting to get comments on each rider's BP because I'm sure there are good and bad things obscured to my untrained eyes. I must also, before the pictures, say that when watching through hundreds of pictures of each rider, I did notice that the BP changed for all of them, suggesting an adaption to the needs for each corner. In other words, they did not seem static over a period of years, nor from one corner to the next. Hence it is hard for me to tell if I got the most representative pictures of each rider or not. PS! There are two images of both Roberts Sr and Rossi! PS! Due to restrictions of images allowed, this will have to go over several messages. Ago Sheene Roberts Sr Uncini Lucchinelli Spencer

I cannot see anything I wrote that would contradict with your statements there?

I guess you could miss your shift/clutch timing, but that probably doesn't happen very often. Most people are more likely to miss the rpm match when blipping the throttle. Let's say you need 12000 rpm for a smooth engagement of the next lower gear. If you pull the clutch and only blip to 8000 rpm before releasing the clutch, you will have a shock that will still be softened, especially since the gears are already engaged. If you hammer in the next lower gear with even moderately too few or too many revs, you will hear it very, very well because nothing gives. Doing clutchless downshifting is fine if you master it, and it will be easy for some to learn, harder for others. Personally, there are other things I'd focus on before worrying about acquiring this skill. After all, most world champions have - and do - use the clutch on downshifts, so the practice cannot be considered completely debilitating

Another myth perpetuated by the internet and simply untrue. How convenient to omit the other half of the information in your quote. You should be a politician. Do you honestly belive a badly mismatched downshift without using the clutch will not cause greater stress on the gearbox than if you let a slipping clutch take up most of the shock?

Even when you have a bunch of quite good riders on the track at the same time, like in AMA racing, things get scary when the fast guys lap the slow guys - few will experience to be lapped more than once*. I couldn't imagine being on a track where the difference may be that the best is nearly twice as fast as the slow riders - it would make downtown rushhour traffic seem calm and safe in comparison. * I would actually prefer to see riders being flagged off before they get lapped. 15 years ago, you could even see lapping in GP racing regularly, and it often made for some dangerous situations. This lead to the 7% rule; if you were more than 7% off pace during qualifying, you weren't allowed to start.

I do it when the clutch cable snaps But it takes concentration and if you mess up - as we humans are unfortunately apt to do from time to time - it will put more stress on the tranny than if you at least partially disengage the clutch. But each to his or her own - if you can master it without thinking, keep doing it. If you do not care to learn it, there is nothing wrong with using the clutch - it is there for your convenience

Most of all it shows poor editing I have never been a great fan of watching others wait Good thing there wasn't a crash, though

I wonder - how much has the "hang-off" style evolved and improved since we first saw it about 40 years ago? Mike Hailwood wasn't convinced that it was any better than "just sitting there" - and he proved it by winning a few races when he came back to the sport in 1978 and '79 on both those days eqv. of superbikes as well as on 500 GP bikes. Since it seems unlikely that anybody could copy that feat today, it must mean that the style has evolved significantly and become more efficient. I'd be grateful if somebody could explain how and why it is performed to a much greater effect now than back when.

Are you saying Spencer wanted people not to hang off?

This is how bits of it works

It depends also on how they are stored. Cool and out of sunlight gives them a longer life. Also important is your pace and riding style as well as the behaviour of the tyre. Unused tyres perfectly stored - off the rim and standing in a dark, cool room without chemicals - can stay fine for at least a decade*. Once used, though, deterioration starts to set in regardless of how it's stored. I have used a front street tyre as old as 13 years that was perfectly OK for riding on; it had lost some of the grip but was still very predictable. In fact, I've ridden brand new tyres that were worse. But some tyres can behave erratically when old. I guess it comes down to comparing the price of a set of tyres to that of a potentially crashed bike. *Although virtually as good as when it was first made, it will still be a decade behind in development by then

I believe - as I wrote - that fewer power pulses and/or crowded power pulses improve grip. In fact, there is no denying that. What I tried to get through is that nobody has fully understood WHY it is so, that it is down to using logic and speculation and not objective science.

Throttle rocker is something I have considered for just the reason described; quite often, the friction between grip and glove is poor (I have heated grips), requiring a too firm clench of the fist just to maintain throttle position. Seems I must buy a rocker now.

From what I have gathered, the "eggsperts" doesn't fully understand why lesser firing pulses gives more traction. At 10-15000 rpm, the pauses between each firing must be considered infinitesimal at best. 12000 rpm = 200rps and whether you fire them evenly spaced at 400 puffs per second or in one big whack and 100 bangs per second, it still seems unlikely that you could have the tyre grip between the slips before the next power burst hits. In theory, having many cylinders and even firing spacing should provide the most tractable and flexible power because the crank speed will not vary nearly as much as if you have a single cylinder. But in real life, fewer throbs seems to work better than many thuds when it comes to traction.

It is probably a confidence thing and doing it until it becomes second nature. For me, trailbraking (on the road) is natural and I need to make an effort to set my entrance speed early and drive through the corner under some power. I feel much more comfortable regulating the grip on the front wheel than the rear, a habit I formed during years of bicycling andmotorcycling on snow and ice. Even if it isn't the ideal way to ride

Many champions have used lots of trailbraking. In fact, you cannot even hope to win a world level race IMO without some degree of trailbraking today. Or are the examples of riders that doesn't trailbrake and still run at the pointy end? If there are, I'd be interested in learning who so that I have something to look for while watching this season's races.

I can only talk from personal experience, which is that I have never* (in 30 years of riding) suffered a front wheel washout when chopping the throttle midcorner, or even getting on the brakes. However, if I do have to slow midcorner, for whatever reason - be that fear, starting to slide or facing unexpected obstacles - I simultaneously pick the bike up if I'm already at or close to full lean. I can pick it up a lot and brake very hard before easing up and leaning in again at a slower pace, or just pick it up a little and use just a bit of slowing, depending on available room etc. There is, though, little doubt that loading up an already heavily loaded front tyre with deceleration can cause it to overstep the available traction - hence the picking-up-the-bike thing. *It has actually happened twice; once at moderate lean when I hit a big bump that sent me skywards and made me land on a locked front wheel. The other time was when I was faced with two cars coming towards me on a narrow road - no room left for me - and I locked up the front and went down. I think. I have no recollection of the incident after stopping one of the cars with my face However, I digress as neither of those episodes can be considered usual occurences

With the new satellite bike having been described as much closer to the factory prototype than in previous seasons, LCR Honda Team Manager Lucio Cecchinello offered his thoughts on the new machine following Sepang: Cecchinello continued: “The bike is very different, because it is shorter and the weight distribution is different. It has transferred much of the weight to the rear to gain traction, and the centre of gravity is also higher. Right now it is giving us a lot of work because we must find the correct setting for Randy.” So while Yamaha has a long and low bike, Honda has gone ahead and shortened and raised (CoG) its machine once again. This most likely to suit Mini-Me, since his small stature and very low weight won't make the bike as wheelie-prone as it will for bigger, heavier riders. Perhaps these changes can explain why the Hondas were generally off pace during the Sepang test? I believe it is a mistake to develop the machine around Pedders because he has a very unique (PC speak for child-like) physique. They would have been better off designing the machine around an average sized rider and then made one-off fuel tank, seat and pegs for the midget. He could also have his own, short swingarm. I think Melandri is equally fast to Pedrosa if given suitable equipment - after all, they both have a second place championship position to brag about - and he would be far more representative to build the bike around so that it would suit more riders, enhancing Honda's chances of success. But perhaps it's all intentional? Last year those pesky customer bikes had the hide to finish ahead of the Repsol bikes more than once. With Melandri on one, there was a danger that it might happen again. Test times so far seem to indicate they have eliminated this problem

To my extremely untrained eye it looks as if he is basically coasting and simply running out of cornering clearance...

I think this perfectly illustrates how you know when you are using it all and how to save it by staying relaxed and not chopping the throttle