Tyre Pressures

[kevip6]

What tyres are you running?

[adam1986]

I don't want to hijack this thread, but I'm in a similar position to the OP and after a winter layup have noticed some dodgy handling issues.

I'm currently running a rubbish set of Kumho tyres (>6 yrs old) and pumped them up after the winter to 20 PSI and noticed the rear squirming about all over the place under moderate acceleration (albeit in slightly damp conditions). A very kind friend has offered me a free set of second hand T1Rs that I'm hoping to get fitted in the next couple of weeks, do you think these will make a dramatic improvement and do you think dropping the PSI to 18 will make a difference?

[Captain Colonial]

Impossible to say, but one, get rid of the old tyres for sure, and two, how old are the T1Rs? Do make sure there's nothing wrong with the rear suspension, wheel bearings, bushes, etc, check it all for free play.

[peterg]

do you think these will make a dramatic improvement

'improvement'?, yes almost certainly, 'dramatic'?, well that's in your judgement and no one can tell how sensitive your is to the available grip assuming they are no more than a couple of years old and been looked after then they'll definitely have more grip but how much none of us can tell you

and do you think dropping the PSI to 18 will make a difference?

Maybe but I would start on 20 so you're comparing them to the rubbish old tyres as closely as possible - ie. don't change too many things at the same time or you won't know what made the 'improvement' if there is one... once you have felt the improvement of the new(er) tyres then have a play with pressures.

[adam1986]

Ok thanks. I know my post probably wasn't the most helpful given the scant detail, but I'll switch them over and see how it goes.

[dhutch]

Toyo R888's are a semi slick trackday tyre with specialist compounds and a particularly stiff side wall. They benefit particulalry from quite aggressive geo settings - they love camber for instance and will lap up 2 or more degrees of negative camber. They will also respond really well to certain tyre pressures, though its probably a good idea to distinguish between road and track use.

I always thought that one of the main things about the R888, compaired to say an A048 is that the R888 is while both are 'road legal semi-slick' type tread and available in sticker than normal compounds, the Toyo is on a fairly generic road carcase with road going sidewalls etc, where the Yoko is on a slightly more race carcase with a bit more in the side walls.

 

Bringing back a fairly old thread, and while it unlikely to be of use the OP might be to others.

 

 

 

Daniel