IIRC they use 16.5" wheels as well, not sure of the other profile numbers but I would bet that they are at least 190 if not slightly larger.

 

Taken from this website... 2009 Yamaha M1 specs

http://images.google.ca/imgres?imgu...VCP-sF2M:&tbnh=113&tbnw=150&prev=/images?q=Yamaha+M1&um=1&hl=en&sa=N&tbs=isch:1

Wheels: Marchesini 16.5 front, 16.5in rear, available in a variety of rim widths

Tyres: Bridgestone, 16.5 front, 16.5in rear, available as slick, intermediate, wet and hand-cut tyres.

*IIRC, the size is 19/67...

:fork

 

Their tires are huge.. I'm betting they are like 215/75s or some crazy shit like that..

 

yeah I like em, I'd feel pretty confident about leaning those over with the huge contact patch. also wondering what the 'sharkgill' cuts on the airbox are for other than lookin cool

 

I pretty sure the air box is lower than that and the top area holds all the electronics the shark gill holes are for cooling them I think.

 

cool beans. learn all kinds of stuff here eh?

 

Yeah...
I remember reading Rossi's tire at the Long Beach motorcycle sho and it was a 16.5/?/70 I think, maybe even 75% aspect!
It was very tall!

 

pretty sure they use 190 and 200's :dunno

 

it's definitely NOT a 50 series tire, too wide and flat, it's at least a 60 or 65 series i'm sure, and probably minimum 190mm or 200 mm wide...

 

I'm running 16.5's on my Superbike and use either a 200 / 70 - 420 or a 205 / 60 - 420 for the rear and a 125 / 80 - 420 for the front.

Pretty sure Moto GP fronts are similar but they may be using something slightly larger on the rear

Rims sizes are typically

R - 16.5 x 6.00 to 6.25
F - 16.5 x 3.5 - 3.63 I believe

 

the dunlop ntec slicks i run on my bike are 125/80-17 and 195/65-17... and the tires on the gp bikes are bigger, but like previously mentioned they are on a 16.5" rim

 

They might just look wider because there's no tread cuts in them. I remember when my slicks for my stang came in, only 12" wide but looked a foot and a half wide. Motogp rear tires are def def taller tho, but 190-200 is my guess on width

 

Interesting. I always wondered, as well.