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bluninja
12th January 2003, 16:45
So who knows about tyre pressures then ?? Reason I ask is that I've been given loads of advice about tyres, especially with regards to fast or track riding.

I've come across lots of articles and information about road tyres that say that (with a few exeptions) all tyres should be 37 front 42 rear. It basically says that this pressure is needed to give optimal sidewall stiffness. A little less and your tyres squirm around in turns, too much and you bounce around.

My manuals always tell me to check my pressures cold, so what happens when you ride ....Yup the tyres warm up and there is a corresponding increase of pressure. So how do you know what pressure to set the tyres out when they are cold to get optimal temperature when riding ??

TTFN

duke
12th January 2003, 19:59
the 37/42 (F/R) advice is right for hot tyres. When I am at the track, with a new tyre, I check the pressures cold. Then I go out and practice and immediately after practice, when the tyre is hot, I check again and adjust as necessary. Once I know the cold setting for 37/42 hot I only check cold, thats every meeting and usually before a race. Top race teams use Nitrogen, not air in the tyres, to reduce pressure variability.

For road riding it's too much buggering around so I set the tyre as it says in the manual. :bigthumb:

wkid_one
17th February 2003, 11:15
I ride 38psi rear and 36 front on my VTR......you can't forget in this summer weather with road temperatures hitting 40plus degrees - you can expect a 10psi jump in internal tire pressures once they start cooking.

I find 42 to hard on the rear - especially running RennSports which tend to stay too cold at that pressure.  I run OEM pressure on the front as playing with this too much upsets the whole feel of the bike especially with the VTR being a larger bike.

KiwiDan runs the same pressures on this 01 GSXR Thou.....

Try them - they work really well.

 

 

duke
24th February 2003, 10:30
I ran 42 hot on the rear at the weekend and the tyre got cooked and I started sliding about.  The tyre was probably more than 42 on the track and cooled down by the time I got back to the pits and stuck the gauge on.  I came down to 32 cold from 36.  That worked great.  I got my fastest lap :) so  I reckon your 10psi increase is about right in hot conditions.

KiwiDan
27th February 2003, 13:53
Im no expert, but Ive always thought higher pressures were for load bearing machines, this is not black and white so dont jump on me for saying that.

The amount of HP the modern bikes put out really does mean we can no longer run sports touring compounds or pressures.

If your are one for throttling ya bike and have a machine that pokes out a lotta horses i would be looking at 36-36 or even 36-38R.

Race track applications dont apply to road what so ever.

If ya tyre is spinnig up it can be a number of things, eg, to much pressure can limit ya contact patch or can cause less heat.It all shows up with the same simptoms, BEWARE.

Best thing is to check wear patterns and if the tyre is balling up , increase preasure or if its not working up enough decrease pressure.

 

Dan