Tyre pressures

[julianb]

I seem to be topping up the rear on my 600RR every few days. I crank it up to 42psi as recommended, then two days later it's down to 25-28psi.

Could it be that the tyre is not seated just so, or there's a prob with the valve?

I can't see anything obvious like a puncture...


thanks


J.

[Andy Oh]

I'd say best take your bike to a tyre shop and get it sorted asap.

[shot2bits]

I'd say you have a slow puncture - mine loose a few PSI over a couple of weeks but not that much!

[YamR1V64motion]

shot2bits said:

I'd say you have a slow puncture - mine loose a few PSI over a couple of weeks but not that much!

same with mine, although i do have to say the CBR600RR and new model Fireblades seem to be very sensitive to having the tire pressures correct.

[julianb]

Yeah,

I know what you mean 3 or 4 psi and the back end snakes about over road markings and changes of surface. I guess because the bias is so heavily over the front wheel.

[shot2bits]

Although, road racers reckon the recommended tyre pressures are way out - basically designed to make the tyre last as long as possible. For real grip, the PSI should be quite a bit lower... On the track they recommend -4PSI to allow for heat build up increasing the pressure. I've no idea what the ideal road pressures would be for someone like me who only rides for fun and would therefore like as much grip as possible.

[Andy Oh]

shot2bits said:

Although, road racers reckon the recommended tyre pressures are way out - basically designed to make the tyre last as long as possible. For real grip, the PSI should be quite a bit lower... On the track they recommend -4PSI to allow for heat build up increasing the pressure. .

I think you'll find track pressures to be a around 30 to 31 psi front & rear.

[Fats25]

Not sure if this will actually work - but when having bike serviced last week, I had the tyres filled with Nitrogen (I think) by Steve Jordans, cost a fiver. Supposed to stop as much tyre presuure being lost so frequently.

I will keep checking, but will be interesting to see if I have wasted a fiver, or whether it will work!