Yamaha R1 Rear Fuel Tank

[Blade]

Could this be the future ????

Rear mounted fuel tank for better weight distribution.



More info here:

http://www.crash.net/motogp/news/225628 ... -tank.html" onclick="window.open(this.href);return false;

[Cav]

The latest Husqvarna has that.

I really don't see why you would put it there. The weight is high up and potentially behind the rear wheel which means you lose weight at the front with a heavy fuel load under accelearation and you lose stability under braking as the rear will want to lift as it is the furthest point from the pivot point (the front tyre).

The geometry of the bike will also change as the fuel load decreases as the rear will stand up as the weight diminishes (even though the difference will be small it will be noticeable). This would result in less rear grip as the load decreases and an increased steering rake angle.

There's a reason they have been moving engines further forward and lower, to aid in the centre of mass being below the lateral pivot point (the imaginary line drawn between the axle of front and rear wheels). The reason is to be able to brake and accelerate harder as well as making the bike easier to ride (less fatigue).

Im' sure for an endurance race this is something that would be useful as a super size fuel tank means less fuel stops meaning a faster average lap time through a race. For a typical sprint race there is no benefit that I can see

[Kwacky]

It makes sense to have the filler behind the rider and away from the engine. You can refuel and lever the rider in place and the mechanics to do their stuff without worrying about fuel going everywhere and the refuellers getting in the way.

[Cav]

I think the ultimate place would be where the gearbox is but obviously that spot is taken...

[Kwacky]

It's a bit hard to fill up there as well

[Cav]

You'd have to have a port on the side with an elbow connecting to the tank probably.

Due to the fuel load affecting the behaviour of the bike is it quite important to have the fuel tank in a neutral place where is has as little effect as possible - at the centre of mass.

I personally ride a bike exactly the same with a full tank to an empty tank - I can't tell a difference

[Kwacky]

I can. It's very different on the SX as the tank is so large. An extra 17 litres of fuel shows up when you're tipping in or braking hard.

[Blade]

They know what there doing and it's good to see them trying new ideas as that's the only way to make progress.

[Monty]

I think thats just the fill point and the tank is where it always is

[Kwacky]

I think thats just the fill point and the tank is where it always is

It is.

[Blade]

“It's not completely [decided] if we will use this tank set-up yet. We know we have two litres more fuel to put somewhere so this idea was created and we are trying it,” Zeelenberg continued.

“Basically we can go everywhere [with the two litres of extra fuel] but you cannot go a lot more forward because you have the airbox. And if you make the airbox smaller, that would be a problem!”