RickBetterley

My shaved (4/32nd originally) Toyo RA1As are just down to the wear bars; this is after 25 heat cycles.
Anyone care to hazard a guess as to how many more heat cycles I have until they are corded? It would be good to know about how much they have have left.
Thes are DE tires, and are generally corded before they go greasy.
TIA

TheOtherEric

Check out this thread:
https://rennlist.com/forums/racing-and-drivers-education-forum/281821-odd-wear-on-ra1-s-at-the-rear-see-pic.html

I'm well into the wear bars, and the entire outside edge (on the right in the pic) is worn off, yet guys were saying they're only half-way done!! I haven't tested the theory yet.

Matt Marks

They will run just fine until they look like slicks, and will likely continue to get faster. Just keep an eye on on the shoulders - when you start to see what look like small circumferential lines at the shoulders they are getting ready to cord.

m3bs

My experience has been that 25 cycles is about the point the grip goes away. You can run them on down to the cord, but you might find that your street tires stick better! I start with a partial shave (4-5/32, not the "race" shave of 3/32), and find that I now run out of rubber about the same time as I run out of grip.

forklift

This is what I think also. I keep on hearing they are fast right up until they cord, but mine are really close to cording right now and I was a second off my times at SPR a few weeks ago. ...might have also been the warmer weather or a slicker track, but for whatever reason I didn't feel as though I had as much grip.

RickBetterley

Might well be true; car was geting loose during the last run group at Mont Tremblant; admittedly it was NER's Enduro, so I was out for about 45 minutes (with a 5 minute break in the middle). I was suspicious that the tires might have been hotterthan usual,and was tired, so I came in.
Of course, the car might have been loose because I was tired.
I'll report back after my next event, which is 2 open track days at the Glenn.
Thanks

sleder

Keep checking and adjusting the pressures, but I have gotten 50 heat cycles from mine on a regular basis.

RickBetterley

Good to hear from you, and thanks for the suggestions; will do.
I was interested in the question so that I could develop kind of a milestone ('when the tires are at the wear bars, I have perhaps 25 more heat cycles'), but will of course as always watch the wear and pressures like a hawk.
Had a great time at Tremblant - the music festival is fabulous, as is the track, of course. You have got to join us next year for both.
Off to WGI this Sunday for 2 days of open track (Monday and Tuesday); yahoo!

jerome951

If you're just down to the wear bars you have a lot of life left. As Matt said, when you start to see indentations in between the outer shoulder blocks you're almost to the cord.

I've found RA1s are at their fastest when they're nearly slicks, though for my heavy car, that's only about 25-30 heat cycles.

Jim A (Forklift), SP didn't have much traction a few weeks ago (at Hyperfest). I was running newish Hoos and could barely beat my best times on RA1s.

sleder

I wanted to and should have gone to both. My plan was to do the CR and then DE...one thing lead to another and now, I am going down to summit for a de and I'll get some practice in for the CR in Oct. Seems like you are getting some use of the new vehicle...It looks great and use it with the best of enjoyment!!!Hope to see you soon.

RickBetterley

Thank you
The 'indents between outer shoulder blocks' comment is helpful as well.

forklift

Cool, thanks. I thought that might be the case, but wasn't sure. I wonder why the track had so little grip...?

M758

In my experience RA-1 last until the cords or they noticeable have no grip. I have gotten 48 heat cycles from 1 set and 35 from a couple others. This is until they simply don't stick any more. However they have been virtual slicks for 10-20 heat cycles long before they got old. When they get down to the bars they are looking really good. I perfer to race on tire with 25 heat cycles vs ones with less than 5 even if shaved. The older tires simply work better on my car.