tyre wear question

Wheels, shocks, forks, frame
dave32
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Post by dave32 »

Luders wrote:I think Dave is just saying that the tyre is being subjected to more braking and weight forces, than what a super moto would put on the tyre and therefore the recommended pressure may not apply in your case and a couple more psi would be required.
Thanks thats what i should have said :D
also a proper supermoto is going to weigh at least 30kg less than a KR,and there use on loose dirt and the riding position,supension travel is night and day of a road racer so would put different demands on the tyre.
It may not be the tyre pressure causing the tyre to rip up like that,it could be the settings are way out (something is) and overloading the front tyre (which is whats happening).
might be worth seeing what the weight bias is front to rear with a set of scales,it could have too much front end bias,thats why the rear is looking fine.
still on the tyre front i would run a pair of whatever you choose i dont see a gain in using one make for the front and another for the rear,there designed to work together (profile,tread pattern and compound).
26 psi is was too low on a 130kg machine,whatever make the tyre is.
How much sag does the rear have static and then with you sat on it (should be 0mm staic and 25 to 35mm with the rider)?
Just need to adjust the spring preload to get this right.
also the front end wants about 25 to 30mm with you on the bike,and the front and rear should compress/rebound at the same speed and time.
You need to get the sag and ride height right before you adjust the damping otherwise you wont get anywhere fast.
Rocket
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Post by Rocket »

I think my race bikes must be miles out,
Front weight is 65kg on 1 bike and 66kg on other and 60kg on rear of both,
My ktm 525 sm road bike weighs 61kg front and 62kg rear
Maybe if they were setup properly I would go even quicker
Rocket
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Post by Rocket »

I think my race bikes must be miles out,
Front weight is 65kg on 1 bike and 66kg on other and 60kg on rear of both,
My ktm 525 sm road bike weighs 61kg front and 62kg rear
Maybe if they were setup properly I would go even quicker
andy b
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tearing

Post by andy b »

Looks like cold tear to me, Dave has the right idea i run supercorsas with a soft side wall at 31 front and 29 rear. I know the dunlop gp has the hardest side wall then i do believe its the michelins.
Firstly get the tyre pressure right then make sure your forks are set up properly, sounds like your compresion damping may need a tweak but again try 31lb front 29 rear from cold first.
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scooble
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Post by scooble »

I know that other 250 riders have used them successfully in the past. I upped the pressure a few psi but it still looked ripped. I then changed to a supercorsa front, rode faster and the surface was totally smooth. Upping the rear rearbound damping by two clicks also improved mid corner stability.
john-b
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Post by john-b »

We dont do alot bike wise only the powercup now but you need to find out what the working temp range is then set the pressure so it hits it.
Put a bit to much in it do a couple of laps then drop the pressure to what you want. The amount the pressure rises has too many variables like track temp rider weight set up etc. You need to set the pressure hot then it will be right when the temp comes up if that makes any sense? Setting the pressure cold and hoping when you dont have a temp probe etc is pointless because you dont know if the tyre is getting into its working range if that makes any sense i have been on the wine?

A light car will only rise about 6psi normally i think and obviously a KR isnt heavy so the temp isnt going to rise much. I have no idea if that helps but it might put you on the right track?
I wish i knew something about KR's so i was like knowledgeable about them and everything like what you lot are ;-) :-) :-)
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