Bill Farrell

Does anyone "heat cycle" their Michelin Slicks one time (before racing use) to extend their life ? This past race weekend - I only got 4 heat cycles on my fronts before they were done (ie: worn past the wear indicators).

In this book: Paul Haney says *all* race tires will benefit from a break-in procedure of gradually bringing them up to temp, then letting them rest for 24-48 hours. It allows an additional curing stage for the rubber.

Tire Rack does the process for Hoosiers:
http://www.tirerack.com/tires/tirete....jsp?techid=66
The final curing occurs while they are being shipped.

You can also do it yourself - However, this isn't very practical at the track. Please advise - Thanks !

Dan Jacobs

Bill,
I've tried but to no avail. We all had thousands of reasons to wish it would this weekend

fstockcarrera

I think you should just slow down a bit Bill. Nice time.

J richard

Tried this with Hoosiers and kumho, made no noticeable difference in the tire going off. Best bet is to scrub and let them set. Not sure the mechanical process gets them to temp properly.

Ps:two sets one set from previous weekend and one new. Scrub new during warm up, swap out for previous set for the day, run the fresh scrubs in the morning...wash rince repeat...

ZSA Motorsport

here's my take and experience; Tiv @ Heinlein Racing heatcycles all my tires with a chicken hawk tire warmer. nifty little piece. takes about 1 hour to heat soak a set to 175degrees, let it sit for 30,40minutes to soak .
brings the oils out, and allows him to do the heat cycling in the calm of his shop.

we've tested HCycled slicks and R6s back to back with non-cycled, as best possible at Monticello. while its very difficult to conclude a ton and i would deifnately suggest its not appallingly apparent....i would say that on the R6s for sure, the ability of the tire to sustain falloff is better. noncycled tires i find lap 3 is that magical lap, you get about 5 to 8 more laps in that range and then it fades on cycle 2,3,4 etc. and then you simply get as many cycles as you drive fast vs your tolerance for times falling off. i guess when guys say "i get X sessions" out of a tire, we should really discuss how many sessions within 1/2 second of best lap times, how many within 1 second, how many outside of 1.

but basically heat cycling allows me to get more laps within that 1/2 second of that buttery great lap you get around lap 3 on tires.

the slicks were abou tthe same.

we've also used those warmers at races and particularly in PCA environments where a) they are permitted b) qualfying is green from the outlap, you go out with heat in the tires and pressure on board.

if you're doing an open track test /tune and you come in to pit for 20minutes to recovr or make changes, they are great for keeping heat in the tires to avoid an unnecessary cooling, hardening, ie cyclng. on the other hand your magical lap now moves to lap 1 or 2 which might not be a good thing.

overall, worth heat cycling? if you have access to it, whats the harm? tire rack does it for a few bucks a tire. thats a good option.
my two cents.

jrgordonsenior

Does you cup regularly wear out Michelin fronts in 4 HC's or is this track tougher on fronts than most? My other thought was is your front end set up real soft (shocks and bars) so that you're scrubbing the fronts in turns?....

Bill Farrell

I ran the Heat Cycle experiment on the Michelin N1 Spec tire (Scrubbed for 5-6 laps and let them sit for 2 weeks before the Lime Rock Race).

RESULT: I got the same results as Dan Jacobs, J Richard and Steve Goldman. For Michelins - NO BENEFIT for Heat Cycling. They fell off significantly (2 seconds slower compared to a previous 55 second lap - ie: 4% performance drop) during the 4th heat cycle. I should have simply trusted Dan Jacob's recommendation !

J richard

^^^^
Ahh I figured out your problem. You have to keep the tires in contact itch the track to get a good heat cycle

ZSA Motorsport

not suggesting you didnt, but 5,6 laps, in my estimation is a scrubbing off of reasonable material. plus, i believe most companies have prescribed heat cycling process, i think its something like, one lap easy, another lap medium, then FULL tilt, and get off the tires.

as i mentioned, thats why i kind of like the tire warmers, heating blankets, chicken hawk warmers. you can cycle them without losing any material. plus, as i mentioned, the real value in a venue where they are permitted is that you go out with some heat and pressure in the tires. i can throw down a fast qualifying lap on lap 2, amybe 3 and done, saving tires, etc. and have more security in knowing im going full boogie on a tire that has reasonable temps and psi in it.

cstreit

I had an interesting experience with Hoosier Slicks at the NASA Nationals last year.

The tires that were not heat-cycled never felt like they came in fully. They were CLOSE, but always had a slightly greasy "edge" to them. Like they were at 90% rather than fully gripping. It was frustrating to say the least. I think I would have been better off on the 5 heat cycle tires for the final race rather than the 0 heat cycle tires.

Live and learn....

mikew968

I had the same experience as Chris on sticker R6's. I am finding that scrubbing them in and letting sit for at least a day or two makes a huge difference.

HiWind

Thanks ZSA - nice to hear the detail.
In my experience you're def right about lap 3.
I scrub in with 3-4 laps and no hard breaking in first lap to warm, just some weaving, then pop onto jack stands for the night. It feels like it make for 1-2 more 'proper/fast' HCs but at the .5 sec off level, not at par.

roketman

Bill
I was happy with your results!
Keep up the good work!
LOL
Seriously ,Good luck at the Glen!
Ron

analogmike

The track was REALLY show for the second race so take that in consideration, at least a second slower than normal in a GT3 cup.

HiWind

Ps - anyone running Pirrellis?