why is he faster?

Yes, it is the 'setup', broadly speaking, which is different.

The engine mechanics configure the delivery of power based on two main variables out of many: torque and rpm. Everyone seeks to smooth the relation between the two, so the rider can count on a predictable and uniform response in between gear changes, for instance. The top speed in a mere by-product of how they mapped the engine to optimise many other factors. Manouvrability and curve speed matter more than top speed in straights in technical circuits.

From a spectator's point of view, +/- 20 km/h may seem a lot when two bikes go in parallel in a straight, but you'll see that it isn't that decisive. The 'slower' rider may decide to outbreak the other (if he can or if he affords to punish his tyres harder, for instance). If anything, slipstreams may eventually favour one or another, but again top speed isn't materially significant.

Top speed doesn't decide any race or better results in the long run. Ducati 2005 is a valid example. At the level motogp riders are competing, it is the man's ability and intelligence which makes the difference, bar desperate cases of machinery limitations (Kawasaki) or tyre ones (Dunlop).

20km/h ?!?!? That's massive I don't know where did you get that Katt, The difference between Crashey and Dani in the last FP was just 1.2 km/h, which makes more sense.

The top speed depends on many variables, Engine mapping, braking point, aero coeff of the bike+guy, fuel weight on board, tailwind, and a few more.

The only way 2 riders on the same bike would get a 20km/h difference top speed is that one of them would have made a mistake and brake FAR too late.

Katt, I think the 20kmh figure you have in your head is from Le Mans. Stoner was consistently much faster through the speed trap there. This is because the speed trap is actually on the first bend which some most riders back off a lttle for. I think Stoner was holding it flat through there - from memory he ran off there in one of the practices - I guess he was pushing it!!

Also, the top speed has a lot to do with exit speed of the last corner -
Given equal bikes, the more speed they can carry through the corner and the better they can get the rear end to hook up, the higher the speed.

I noticed that as well Katt and wondered why? I reckon it's a combination of slightly taller final gearing, good drive off the final turn, and Casey's height allowing him to keep a small shape on the bike which would be helped by the fact he's fresh off a 250. Any racer knows that the corner leading onto the straight is very important to make a good lap time, Casey's obviously making a real good job of it.

<div class='quotetop'>QUOTE (vespix @ Jun 17 2006, 11:01 AM) <{POST_SNAPBACK}><div class='quotemain'>From a spectator's point of view, +/- 20 km/h may seem a lot when two bikes go in parallel in a straight, but you'll see that it isn't that decisive. The 'slower' rider may decide to outbreak the other (if he can or if he affords to punish his tyres harder, for instance). If anything, slipstreams may eventually favour one or another, but again top speed isn't materially significant.

Hi Vespix, 10kph is significant. Or 6 mph in £GBP. Miles per hour roughly works out as feet per second. The final few seconds of a straight can be crucial if someone's got a 6mph jump on you, in 3 secs they could gain 18 feet. Thats a lot to make up on the brakes and make it stick.

It`s gotta be the setup, right? Pedrosa`s weight would only be an adavntage in terms of acceleration, not top speed. one of the first laws of physics is Force = mass x acceleration. So on the same bike (The RCV) putting out roughly the same amout of power (Depending on tuning) therefore the same amount of force to push the bike out of corners, Dani`s smaller weight means bigger acceleration for the same amount of force. It means he can reach the top speed qucker, it wouldn`t really help raise the top speed at all, other than because he can get there so quickly, he can squeeze a little bit of extra speed outta the bike before he has to brake for the next corner.

Skid has been the only one to really mention gearing and I think that's where the differential in top speeds is hiding. Just my opinion.

<div class='quotetop'>QUOTE (skidmark @ Jun 17 2006, 05:08 PM) <{POST_SNAPBACK}><div class='quotemain'>Hi Vespix, 10kph is significant. Or 6 mph in £GBP. Miles per hour roughly works out as feet per second. The final few seconds of a straight can be crucial if someone's got a 6mph jump on you, in 3 secs they could gain 18 feet. Thats a lot to make up on the brakes and make it stick. Nicely put and very true.
Anyway, the rest of my post was about the relative irrelevnce of top speed figures. I think that the Shitzukis were the 'fastest' yesterday but that didn't help them a lot. Kevin Schwantz would agree on that point, I think.

<div class='quotetop'>QUOTE (richo @ Jun 18 2006, 03:12 AM) <{POST_SNAPBACK}><div class='quotemain'>Dani`s smaller weight means bigger acceleration for the same amount of force. It means he can reach the top speed qucker, it wouldn`t really help raise the top speed at all, other than because he can get there so quickly, he can squeeze a little bit of extra speed outta the bike before he has to brake for the next corner.

I try to find the logic in that but fail. Either his light weight help his top speed or it doesen't, make up you mind.
In fact, on a limited straight like on a track, more accelleration means higher top speed, given all other factors equal. But here is the mystery: Dani has been (way) down on topspeed compared to most other hondas at almost all the tracks this season. Why? He should have the advantage.

The theory is that his size screws up the aerodynamics witch play an important role in accelleration in the later 2/3 of these long stretches.

Stoner was fastest again with 334 km/h, Pedrosa second with 333.2. Honda powered machines were 1-7, The Ducatis, Yamahas, Suzukis and Shinya's Kwaker were all about 6-8 km/h slower than Stoner.

<div class='quotetop'>QUOTE (Babelfish @ Jun 19 2006, 07:51 PM) <{POST_SNAPBACK}><div class='quotemain'>I try to find the logic in that but fail. Either his light weight help his top speed or it doesen't, make up you mind.
In fact, on a limited straight like on a track, more accelleration means higher top speed, given all other factors equal. But here is the mystery: Dani has been (way) down on topspeed compared to most other hondas at almost all the tracks this season. Why? He should have the advantage.

more accleration dosent automatically mean higher top speed. It`s not like if you put the bike on 100km of flat, smooth, straight road and got Pedrosa to go flat out he`d just keep going faster and faster and faster. At some point (ie the bike`s top speed) it stops acellerating and just stays at roughly the same speed. So on long straights, like Catalunya, if Stoner can get the RCV going flat out in top before he has to brake, his top speed should be about the same as Dani (without taking setup into account) But if it was a shorter straight where they dont reach top speed, Dani should be able top get more speed out of the bike because he can accelerate quicker, and while other riders might reach, for example 250kmph at the braking point then slow down, Dani might reach 250 a few tenths of a second faster so he can get the bike to a higher speed before he has to brake. But that`s just hypothetical. The reality is it`s obviously not a huge advantage, because Pedrosa`s not winning all the time.