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d2dracer
April 15th, 2009, 09:46 AM
I wasn't quite sure where to put this, I hope this is the right place. Last week at the track, I was using my new tire warmers for the first time and by the end of the day towards the middle/right side of the rear tirewas pretty riped up. I think I heard it was called cold burn.

Anyway my question is are the tires still good or do they need to be replaces before I go to the track again?

Also... how can this problem be avoided in the future. Maybe by giving the tire more time to heat up?

TIA!

dragos13
April 15th, 2009, 09:52 AM
Let me ask a couple questions..

What type of tire?

How old are they?

What tire pressure?

What temp do your warmers go to?

Sounds like you might have been experiencing cold tearing. I had the same trouble with my tires the first day at HPR but after bumping up the rear tire pressure, the problem went away. Unless you are down to the tread depth indicators I think you should be fine running these tires still, given they are newer tires not old takeoffs from last year.

eklew
April 15th, 2009, 09:57 AM
Could it be suspension set up as well???

d2dracer
April 15th, 2009, 10:00 AM
Pirelli's I am not sure how old they are... at least 7 month very little usage though. Tire pressure was set 25/25 cold which was probably not right for the day.

Tirewarmers are chicken hawk standards.

dragos13
April 15th, 2009, 10:31 AM
Could it be suspension set up as well???


Very good point Eldon

Sounds like the tires are just old and need replaced. I woudn't troubleshoot suspension or anything like that when you are running tires over a half year old.

My opinion (read: worth very little) I say get some fresh rubber on there. Talk to the vendor to figure out what pressures you should be running. Chicken Hawk warmers should work great. If you are still getting the tearing then check rear rebound etc. Right now, I would be willing to bet that the age of the tire has caused the compound to become harder. Even though they have plenty of tread left, the rubber itself will get hard and could be the reason for tearing.

toptier
April 15th, 2009, 11:12 AM
I think it's the Pirelli's. I know 2 others and myself that were experiencing cold tear on the right side of the tire last Friday. I switched to Michelin at lunch and had no problems with tearing.

gsnyder828
April 15th, 2009, 11:30 AM
Anyway my question is are the tires still good or do they need to be replaces before I go to the track again?

Also... how can this problem be avoided in the future. Maybe by giving the tire more time to heat up?



Rather than accepting a bunch of speculation from Michelin riders as fact - take the tire to someone who knows Pirellis (i.e. Mike @ Faster!) and have them assess how bad the cold tear is and what you should do about it. Depending on how bad it is - the tire may be fine to continue to use. Age is not necessarily an issue in this case.

Also ask about what your target pressures should be for the tire you're running - and remember Pirelli sets HOT pressures, not cold - so that may have affected things. Different compounds may also be more susceptible to tearing - especially on new pavement - so again, see what your tire vendor recommends. :wink:

Edit: You can get more info on Pirelli tires/pressures, etc here: http://www.diabloracer.com/

Throttleroller277
April 15th, 2009, 11:34 AM
Wow...pull the clutch in...

I doubt it is the age of the tire! This Cold Tearing / Feathered look is very common at brand new race tracks. We have seen this at both Miller and Hastings, when those tracks were brand new. We have seen this on both NEW and USED tires. Changing the pressure does seem to change things, but it also depends on the Manufacturer. Going up on pressure helps the Michelins, but that does not necessarily mean that it will be the same for the other. As stated earlier, check with your tire vendor. From my experience on these new tracks, we either see this "tearing/feathering", or the tire is baby smooth. It never seems to "Ball" the rubber up.

As for suspension........... Often times a "well set up bike" will see this as well. Suspension can make this tearing appear better or worse, but not necessarily make it go away. Often times if the "tearing" is consistent all the way around the circumference of the tire, then it is most likely a tire pressure issue. If the "tearing" is inconsistent around the tire, and there are gaps or a thinner band within the "tearing", then that usually is a suspension issue.

As for re-running the tire....... depends on the amount of rubber still on the tire (as Dragos said), and/or whether or not it will effect your confidence. 8)

My 2 cents...... 8)

dave.gallant
April 15th, 2009, 01:48 PM
I think it's the Pirelli's. I know 2 others and myself that were experiencing cold tear on the right side of the tire last Friday. I switched to Michelin at lunch and had no problems with tearing.

:roll:

I switched to Avons this season. I swear that (and a giant pile of bullshit) will fix all my problems.

benfoxmra95
April 15th, 2009, 06:14 PM
Wow...pull the clutch in...



Exactly!!!!!!

You guys are bumping off the rev limiter.

I highly, highly, recommend everyone scrub some tires at pueblo before the hastings round and the HPR round.

HPR has a track surface very similar to hastings, and at hastings, when in not perfect temperarture conditions for racing, will cold tear a tire.

It has been found that if you scub in a set of tires at pueblo for 10 or so hard laps, then put them away and remount them at hastings, it hugely combats cold tearing, as that heat cycle in the tire helps it.

As for the above comment of the tires being too old...? well that's an incorrcet assumption. I've raced/practiced many many times on tires that are 2 and 3 years old. On friday sat and sun at HPR last weekend I was running a rear tire that was made in 2005. Now im not reccomending it, and i can't speak for other brands abilitys to do this but I myself would put on any pirelli or michelin that was made in the last 3 years and run the dog crap out of it.

Btw all the tires i have for sale this year have been manufactured in the last 3 months.

pressure, suspension, track temp.....that's what you need to pay attention too.

Wild Cheetah 612
April 15th, 2009, 09:32 PM
[quote=Throttleroller277]I highly, highly, recommend everyone scrub some tires at pueblo before the hastings round and the HPR round.

Here Here!