Another tyre pressure question

[Red Devil]

Did a search on this and looked on google but can’t really find a solid answer. I’m going to be on track from early next year (end of January onwards) so it’s going to be fecking freezing! Do you drop or raise your tyre pressure when the track temperature is low? I run metz racetecs (normally K1 front, K2 rear) and on a normal day run 30 hot which I set in the tyre warmers after they have been cooking for a while.

My guess is that you would raise the pressure a couple of PSI to generate more heat? The quicker you are the lower PSI you can run which allows the tyre to deform more = more contact patch but you have to be pushing the tyres enough to keep that heat in them.

Could be completely wrong…what is your opinion?
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Thundersport Pre-National Sport 600 2014 #92
EMRA Roadstock 600 2013 - 3rd
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[Wafer_Thin_Ham]

In my opinion, set your pressure for the first session in warmers to your 30 odd PSI.

Then check them as soon as you've come off track after the first session and adjust accordingly to your usual "hot" pressures. This'll mean your pressure will be the same regardless of the time of year.

Used to work for me.
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[Deano]

[Red Devil]

Cheers guys

What pressure did you aim for straight off the track running metz Dean?
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Thundersport Pre-National Sport 600 2014 #92
EMRA Roadstock 600 2013 - 3rd
www.facebook.com/MattJohnstonRacing

[Deano]

[bladerunner]

Exactly this. Measure your tire temp just before you take them out of the warmers and again as soon as you pit. That way you'll know what to expect when on track! If it's jan and cold maybe run a few psi more to start with during winter time as the track temp is low....during summer running maybe a few psi lower as tire heat. Builds with the extra grip and inflatetes the tire temp during a race. It's a bit suck it and see depending on the bike.the tires you use and how you ride tbh. As well as each track you ride. Plus or minus 4psi from the recommended is a good base line to see how it feels. The lap times show the rest
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Current bikes...cbr929, KDX200's, Rd125lc mk2, RGV250's

[Red Devil]

Cool, cheers guys! Wanted to check the way I was planning to do it was correct to save me crashing for a silly reason like pressures.
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Thundersport Pre-National Sport 600 2014 #92
EMRA Roadstock 600 2013 - 3rd
www.facebook.com/MattJohnstonRacing

[Blue_SV650S]

The lower the pressure, the more deformation, the more heat generated ... increasing pressure, reducing deformation ... the tyres are kinda self governing (within reason).

I have never set my pressures HOT, but am surprised how low people are quoting the HOT figures to be. They are the sort of figures I ran cold

I found racetecs at 29.5F 28R (cold) on an 'average' temperature day worked best for me ... I never varied more than 1psi from that.
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The purpose of life is to fight maturity.

[Red Devil]

Yeah I’ve done a bit more reading up on this and that’s correct:

Lower pressure = more carcass deformation = more heat generated
Higher pressure = less carcass deformation = less heat generated

I’m going to start having a play with this next year once I’m happy with my set up as I’m going to have a lot of track time and see what works well for me.

What group do you run in on track?
____________________
Thundersport Pre-National Sport 600 2014 #92
EMRA Roadstock 600 2013 - 3rd
www.facebook.com/MattJohnstonRacing

[Deano]

[Red Devil]

What year onwards is classed as the 'new' interacts now Dean?
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Thundersport Pre-National Sport 600 2014 #92
EMRA Roadstock 600 2013 - 3rd
www.facebook.com/MattJohnstonRacing

[Blue_SV650S]