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For what it's worth going to a 200 rear more often then not makes the handling worse. My Ninja H2 had a 200 rear std from the factory and handled very well however I took a punt and went to a 190 and it handled even better! . I was told "oh you don't wanna mess with it" from guys that don't know anything or people that have never been out of the comfort zone. But in the real world bum on seat riding and experience you can tell if something works or not. Wasn't recommended for TC corruption possibility reasons but even so handled noticeably better. I was careful though to get a tyre virtually identical in circumference not to change the geometry of the bike ( which I was very happy with). Changing even what would be regarded minute (in circumference) by most people does change pretty dramatically the handling of the former setup. I would say it's not the way to make these handle better but perhaps going one size smaller would be a better bet in that regard. Going to a 200 rear might look cool but in the next corner look out. Of course going to a bigger tyre is going to mess with the TC capability thresholds etc.
As for the comments on the OEM tyres are crap (that's interesting) although they aren't my choice of tyre, correct pressure and suspension setup they are fine in my opinion just have bad durability and don't last as long as the Michelins that I am used to.
Jeffro
 

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Discussion Starter #23 (Edited)
For what it's worth going to a 200 rear more often then not makes the handling worse. My Ninja H2 had a 200 rear std from the factory and handled very well however I took a punt and went to a 190 and it handled even better! . I was told "oh you don't wanna mess with it" from guys that don't know anything or people that have never been out of the comfort zone. But in the real world bum on seat riding and experience you can tell if something works or not. Wasn't recommended for TC corruption possibility reasons but even so handled noticeably better. I was careful though to get a tyre virtually identical in circumference not to change the geometry of the bike ( which I was very happy with). Changing even what would be regarded minute (in circumference) by most people does change pretty dramatically the handling of the former setup. I would say it's not the way to make these handle better but perhaps going one size smaller would be a better bet in that regard. Going to a 200 rear might look cool but in the next corner look out. Of course going to a bigger tyre is going to mess with the TC capability thresholds etc.
As for the comments on the OEM tyres are crap (that's interesting) although they aren't my choice of tyre, correct pressure and suspension setup they are fine in my opinion just have bad durability and don't last as long as the Michelins that I am used to.
Jeffro
What size tyre did you change to to keep the circumference the same as the original 200/55? 190/55 is smaller circumference and 190/60 is larger!

I have definitely felt an improvement in handling with the 200/55, turns in better and feels more confidence inspiring in the corners. More traction too and as it has been raining heavily the last 2 weeks i know the TC still works fine.
 

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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!
Jeffro
 

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Discussion Starter #25
It does seem crazy that the quoted size does not near much relationship to the actual size.

I have supercorsa sc2 and the 200 is only 4mm wider than the 190. As far as not sitting correctly on the rim because its not designed for it, that is in correct as Pirelli spec a 6inch rim for the 200.

The 200/55 definitely has a bigger contact patch at lean than the original 190/50

To compare to a diavel is nonsensical, as it has a 240/45 so very wide but with a significantly lower profile, so useless ah high lean angles.

If you compare a 190/50 to a 200/55 on the same rim the the larger tyre has more contact area at high lean angles - just basic maths, it is pulled in further so the sides are steeeper giving more contact.
 

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I am afraid you are wrong in regards to the contact patch of the 190 Vs 200 on the same rim at high lean angles. Track work and lots hours taught me that! Read research on tyres in this context and you will see. However, You can believe what you want to believe that's cool and we can agree to disagree
But if you were right why do you think 99.9% of bikes come with the 190?
Think about it.
You actually answer your own question regarding the basic maths...
At extreme angle the 200 will be steeper as you say and not able to be at the correct lower angle for a bigger contact patch. The bigger tyre actually has a "pinching" affect at the rim making the sidewalls steeper at the edge. To use the tyre all the way to this edge now is virtually impossible.
If you like you can reference several books on the subject. The well known Total control book by the very accomplished Lee Parks describes exactly what we are talking about on page 19 & 20 of his book. Worth looking at to educate yourself!
Anyway have great day sometimes we can't always be right my friend!
 

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There's way too much variability in tires for either side to be stated as an absolute. Variation between manufacturer dimensions. Differences in tire pliability due to both materials and thickness. Even weight and suspension settings will change the contact patch at lean. All that can be said with certainty is that Jeffro's claim is a possibility, and every rider should take care when changing anything about the tire they use (sizing, brand, model, pressure).
 

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and another small thing to be taken into consideration.
Normally an oversized tyre takes more effort to lean from one side to the other. Not only the physical profile but also the reciprocating mass is increased. Therefore the bike actually will turn slower unless you put more effort into the same transition.
In the old days a lot of the club racers I would hang around with would often put a smaller tyre on for quicker handling and better grip on the track. If you were less tired (pardon the pun) towards the end of the race you will always stand a better chance of putting one over on your competitors.
Of course things have moved on and bikes are more powerful and tires are whey better. In the real world I don't think it will make a lot of difference, it's all knit picking really.
I've have some pretty good riders pass me on what I would consider pretty $hitty tyres and I wouldn't even have the bottle to attempt what they had just done on some of the best latest rubber!
 

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and another small thing to be taken into consideration.
Normally an oversized tyre takes more effort to lean from one side to the other. Not only the physical profile but also the reciprocating mass is increased. Therefore the bike actually will turn slower unless you put more effort into the same transition.
In the old days a lot of the club racers I would hang around with would often put a smaller tyre on for quicker handling and better grip on the track. If you were less tired (pardon the pun) towards the end of the race you will always stand a better chance of putting one over on your competitors.
Of course things have moved on and bikes are more powerful and tires are whey better. In the real world I don't think it will make a lot of difference, it's all knit picking really.
I've have some pretty good riders pass me on what I would consider pretty $hitty tyres and I wouldn't even have the bottle to attempt what they had just done on some of the best latest rubber!
Here here! Nice to see well informed members !
Your comments at the end of your post reminded me of something similar
Years ago road racing we had a guy on a ****ty old Gixxer with some crappy tyres that out qualified most of us at a meeting. He was very modest about it all, I really looked up to that guy. I thought how good would he be with some decent machinery! Only saw him the one time then disappeared. He really had talent!
Cheers mate
Jeffro
 
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