tyres 998 with 6 inch rear brembo wheel
 

should i run 180 or 190 with this rim, i 've measured it across (with tyre on) and it looks like a 6 inch rim (Brembo cast inside a spoke)
Got 190 on now and planning to fit 180/55 209 GP

What is best?:devil:

if its a 6inch rim 190/55 not 50 is best.
if its a 5.5 rim and i would be surprised if its not, being a standard brembo wheel. go with the 180/55

Personally, in my humble opinion, I would go with the 180 / 55 myself, the bike will turn in quicker and will be easier to hold a tighter line when "on its ear!":)

I think that the rear rim is probably a 5.5 or a 5.75. If you have measured across the rim ( spoke side) and it is 6 inches, then I think this is the case.

To measure correctly, would mean removing the tyre and measuring the inside of the rim, where the tyre beading sits. It should have the measurement on the inside of one of the spokes as well.

I have 5 spoke marchesini rims. The rear measures 6 inches across the rim ( spoke side) but on the inside of one of the spokes. It has 5.75 stamped on it. I run 180/55 and sometimes 190/55 depending on what mood I am in. ;) I do notice that when running the 190/55, it tends to move around a tad when cranked over. This never happended with the 180/55.

Still, I could be wrong. :frog: All I know is when you see an actual 6 inch rim on a 748/916 etc, it looks awsome. Really wide.:cool:

DC..........:burn:

I've been using 180/55 on my 6" Mag, mainly because I ended up with a part worn stock of Rennsports and Super Corsa from running the R6 at the 2003 TT.
As I have no issues with them I can't see the need to try a 190 and if I was going to it would probably be a 190/55 as suggested by Keefer.