The H2 original Bridgestone RS10 tyres which are 200/55/17 have a circumference of approx 2050 mm.
The Dunlop Q3 190/55/17 which I used and selected because it was so close in circumference was 2040 mm. 10mm is nothing when you consider the huge variations you can get from other manufacturers. For example the Michelin 2CT 190/55/17 (which I really wanted to use was 1953mm) so I decided against it.
So we are on the same page the first number only identifies the actual width of the tyre eg 190 is around 190mm wide ( only approx) 200 is 200mm etc, different manufacturers can have up to 5% more or less in size and still be called a 190 or 200. The second size /55 is the profile and aspect ratio of the width (that is 55% of the width of the tyre and the last figure as we all know is diameter of the tyre
So your comment that the circumference is smaller isn't correct as you can see. I chose that tyre specifically for its so close in size to the original 200 I had.
You may be lucky in your comments & application on the 200 gripping better, but it's generally a rim designed for a 190 won't accept a 200 without consequences. The 200 on the standard OEM rim we have will sit
on the rim and have a profile that will hinder the contact patch. At low lean angles it probably won't make a difference but high lean angles the amount of rubber on the road (therefore grip) will always be more with the 190 vs a 200 tyre on that same rim. The 200 tyre will not sit on the rim as it should and at high lean angles the contact patch actually shrinks compared to the correct tyre for that rim. If you have ever tried to ride a Ducati Diavel around a corner? I have they don't wanna turn! And the Harley V Rod? Same thing. Not much fun, look great but not designed for cornering to the same extreme as sportbikes.
Anyway good luck using the 200 must look the part at least and if it makes you feel more confident then heck go for it!
Last edited by Jeffro; 12-05-2017 at 11:22 PM.