Again oh wise ones please come forth. I'm on the street for years and have always judged tire wear by wear indicaters or the cord peeking thru. I see guys changing what looks like an ok tire. Even the race bike I just purchased still has alot of tread but the mechanic ( who is an expert here in Fla) told me I might get a track day out of it or maybe a practice day. I will admit the sides are quite ruffed up. Question is do you know by the seat of your pants feel, looks of the tire, heat cycles ( another topic I need info on), or all of the above? I was told also to get the durometer specs on the tires I will be using (Dunlop 209's) and take the durometer measurements across the carcus (does anybody do this). Thanks for any input here as I have found it somewhat difficult to gather info at the track from other racers cause they all seem to be very busy.
What the hell is a durometer?
This is something you'll have to feel out for yourself. I've raced on tires that others have thrown away, and now throw away tires that others will happily race on. It really depends on your taste, speed, goals & budget.
If you're out to have fun and can handle backing off if the tire slips in order to save money, then run them a bit longer. If you're shooting for podiums and can run the pace to attain them, plan on a few sprint races for a rear tire.
Tires lose grip by the LAP. Heat cycles certainly do affect them as well. How many laps or heat cycles can your tires take? I don't know. It will depend on the tire, your bike and you...
As a novice I was getting 3 weekends out of a rear. That's race and full practice days. Now I get 1 weekend out of a rear. Sometimes less, and that's without that full practice day.
Another thing to consider is the brand of tire. Different brands last "longer" or wear differently according to machine, rider and style of riding. One racers take off will not be the same as the guy in the pits next to him.
For someone who would replace tires when cords are showing, you should invest in a set of take offs, and then a set of new tires. You can then judge the difference for yourself.
A durometer is a calibrated tool that measures the density (hard or soft the compound is). I thought this would be the reply I would get. It is very different for each rider. And it's mostly a seat of the pants feel. I will run the tires on this bike for a practice day then put new rubber and go from there. I will also talk to the tire guy at the track. Thanks for the input.
As others have said it is going to vary based on your style, speed, Etc.
The new tires are going to feel great at first. As I have gained experience I can run my tires longer and lose less speed as they age.
One thing that helped me was to run a track day on tires (the rear in particular) that were really worn out. I was having rear tire trouble the last 3 sprint races on the rear. I did a full trackday on the tires and used that day to get used to the rear moving around more than I had been comfortable with.
Charlie
Thanks charlie I just came from GMD computrac. Had them give me some base line settings on my suspention. I'm gonna use the tires that are on the bike they are well worn but I'll use them for practice on sat. at homestead to get a feel for them.
That will help, but also I think that running worn tires that you've had from new will be better, that way you will be able to feel the differences from new.
A word of caution, I've not been doing this very long so others may have better ideas. It did help me stay comfortable on tires longer.
Charlie
I have yet to see anyone at a CCS event use a durometer. And as Jeff showed us, alot of bike racers dont even know what one is (not saying he's ignorant or anything, its just a tool that usually isnt associated with bikes). But like Jeff said, tires can last for 3 weekends or 1 day. It all depends on your riding style, suspension settings, hp, track surface and tire composition. If I used 3 sets in a year on my F2 it was lucky. Usually I did 3 races a weeknd at 6 events (1 RA and 5 BHF).
my first event i bought a set of take offs from our tire guy and they worked great for me. my last race i was pushing a bit hard and had the rear spin up a couple of times on the final corner but grip was great for a set of tires that someone just didnt want anymore. The wear spots still have a good amount of space left but will more than likely run down before the end of my next event.
it all depends on how bad of takeoffs they are. hell i picked up a free set from one of the guys i race with after he used them for 2 practice sessions (20 minutes each) since he wanted to pick up new slicks....