Tire pressure questions

[Xian_13]

Tire pressure questions

Tires/Bike
(Dunlop 208GPa)
(Kawi 600)

Quick back ground for my question...

While at BHFs this last weekend, I set my tire pressure in the morning with cold tires.
Bike was great thought out practice.
The tires only had 20 laps on them and looks to be in good condition.
Come time for the GTU race, with about 5 laps in... the tires lost most of their usable traction. Both front and rear tires where sliding out badly.
Next morning I did go double check my cold pressures with the Dunlop guy... and double check my tire pressure. (29#s rear, 30#s front)

Once again bike is riding well through practice (same tires... to broke to buy a new set :( )

Just before the MW Superbike race Sunday, I decided to check pressure with my tyre sox on.
Rear tire 37 #s
Front tire 42 #s !!!!

I have only check the tires hot once and I thought they were near equal @ about 35 psi.

What pressure should my tires be while heated up from tire warmers?
Should I even check my tires hot?

[lil_thorny]

sounds like you were running the correct temps for Dunlop. how many laps did you put on during practice. maybe try some take-offs for practice and just scuff the new ones. I only check my tires when
cold. in the am. also, make sure that your gage is calibrated to Andy's. And lastly, are you fighting a handling problem. we usually run faster during the race than we do in practice, agree? are you running a
rear shock( penske or other) when the shock heats-up....the handling of the bike changes...at least in my experience. many things change from practice to racing. you may feel "better" in practice because you
aren't pushing your limits like you do in a racing situation. No offence, try the Michelins... last
mucho longo........ ;D ;D ;D ;D
michelins 31/29
Benji # 30.

[MELK-MAN]

i check when cold.. the pressure goes up when hot. i have checked hot just for Sh**s and giggles but what is "hot"??? the pressure could vary alot depending just how hot. better to check cold i think.
"only" 20 laps.. my tires seem awsome for 1 race..then drop about 1-1.5 seconds after that race. i have always had my fastest times on brand new rubber.

[Xian_13]

I have a Fox shock on the rear of the bike...
I may have handling issues, but thats a differant story.

Maybe my pressure gauge is off, but the reading from 31 to 42 is what is troubling me right now

[tcchin]

What compound(s) were you running and what were the ambient temps during practice and at race time? Also, how long were the tires on warmers and at what temp?

[lil_thorny]

that's norm for heated tires. like melkman,
i too have checked my tires just out of curiosity.
sometimes over 40 psi on the rear.....
i also have a fox built buy Baker (re-valved)
20 laps may be too much for the Dunlops. remember, 20 laps is a GTU. It isn't too uncommon
to go through a rear in a GT. try slicks. try
Michelin ;D  with the heat last weekend, I went through 2 rears and a front. also, remember that the longer(GTU/GTO) you are running the heat cycle,
the greasier the tire tends to get...
Super Dave, correct me if I'm wrong.
for example; I had a new Michelin M2 on the rear
for the GTO it started to fade with about 5 laps to go
but it was still awesome in the sprints on Sun.
lasted 3 more sprints. Granted, I ran 10 races this weekend. But only 2 rears and 1 front which is still in ok condition. I got on average 55 laps out of my rears this weekend. and have almost 90 laps on my s2 front. As far as handling is concerned, I made a 2 mm adjustment on ride height(lowered it) in the rear,
and that helped with the rear tire endurance. I was
spinning up too much. also went down a turn on the compression from 4 to 3. try that for starters.
other than that, I don't know.
Benji 30

[Jeff]

If the bike is set up correctly, you can get 2 weekends with practices, 3 sprints and a gt each weekend on a Dunlop...  (well, I can anyhow...)

[Thingy]

If the bike is set up correctly, you can get 2 weekends with practices, 3 sprints and a gt each weekend on a Dunlop...  (well, I can anyhow...)

Hey Jeff, wait until you drop another second or so.  You will S$%t when you see how fast you go through tires by dropping one little second.

Also, sorry that I did not get to go for a spin on the RR.  THe R6 sure was fun.  It would have been interesting to compare.  In the end, I spent the most time on the 1000, but I turned the fastest time on it by a long shot.

[lil_thorny]

yes Jeff, what Bill said.
when i was in the 16's my tires were lasting all weekend and the whole school at VRS.
now dropping into the 13's....they don't last for half
as long now. And my bike has a pretty good set-up.
Something to consider. set-up certainly aids in the longevity of the tires. the faster i get, the more money i spend!!!!!
Benj. 30

[pitbtch#1]

Thats true the faster u ride the more tires u are going to wear, also the more money u will spend

Heath

[Xian_13]

... try slicks. try
Michelin ;D ...

Would slicks make any differance?
Dollars for Dounuts... there is not that much differance in price from a DOT to a slick...
I have thought about doing this, but doubted it would make any differance to me...

[lil_thorny]

well you can't run the slicks in all events........but
they tend to last longer...i stick with the DOT's
i will be honest and tell you that i've only run pirelli/
michelins. michelins lasted longer than the pirelli's
over all and get much better traction in the rear from the michelins. the fronts pretty much feel the same
on both brands. i wish i could tell you more. also,
i get better longevity by keeping the tire warmers on longer and getting them back on the tires as soon as i pull off.
30