Shaving Toyo RA-1s ?

[Dave B]

I have a 97 Camaro that I run in the Canadian Solo 1 (time trial)series. In Solo 1 a tire may go through up to 7 full heat cycles in a day but not necessarily a lot of wear.( Maybe no more that 30 -40 laps total in 5 lap sessions) I have used Kumho Victoracers 275/40-17 with lots of success but have heard that Toyo RA-1s are very resistant to heat cycle degradation.

 

I know you folks use this as a spec tire and thought you could give me some advice on shaving. The way I see it, shaving will decrease my risk of tread chunking and increase tread block stability but will decrease my wear. Just how bad are these tires at full tread depth and how much slower than when shaved? Also (being both poor AND cheap) how much more wear would I get out of them if I didn't shave them but didn't chunk them either?

 

I am prepared that at their best , the kumhos are likely a bit faster but after a few heat cycles the Toyos may be better. Would this be accurate?

[racercosmo]

The 2002-2003 AI West Champion used about 4 sets of tires total over the 2 years. That included 16 AI weekends, two additional race weekends out of the region, and two SCCA weekends for a total of 38 races.

[turbolx]

As I understand it from talking to many other racers in my region, we expect at least one full season out of a single set. I just bought two complete sets (dry/shaved and full tread/wet) and the shaved tires were only $10/pc more.

[coupe331]

I ran all of 2004 and used 8 or so shaved RA1's. I do not think I could run a season on one set unless I skipped practice sessions, or had a sub 3000 lb car and did not run at 100% all the time.

 

Ryan Walton

[Dave B]

That seem like very impressive wear.

 

Were there any issues with chunking at full tread depth or did you only use these in the wet?

 

How fast were they as they got down closer to slicks? Some people up here tell me they just keep getting faster and faster until you hit the cords.

[DanElam]

We've run both on the RX-7 and have a lot of experience with the Kumhos on the Factory Five car. Both of these cars are lighter though.

 

We do shave the Toyos and pick up some speed. Both of these tires are excellent when it comes to resisting heat cycles and we find that on the RX-7 we can get a full season on either set (assuming no other problems). I certainly wouldn't say that either tire gets faster as you them - they still do have some heat cycling issues, but it's just a lot slower than other tire brands. I would expect the heavier cars to go through tires slightly faster. In any case, even with shaved tires you aren't going to go through the rubber before you heat cycle them (I have plenty of hard sets with lots of rubber).

 

We also run unshaved Toyos in the rain, but would never consider doing that for the Kumhos. We definitely think the Kumhos are faster in the dry.

 

The tires will chunk if you don't get them warm enough. In our experience, we've chunked shaved and unshaved tires if we have tried to push them too quickly before they get warm.

 

For auto-x I am not sure how you get those temps quick enough. My experience is that the Toyos heat up *sligthly* faster which would seem to give them the edge, but the SCCA solo results suggests that Kumho is doing just fine in the hands of the guys who know what they are doing.