Have new 205/40R 16 Falken Azenis RT-615’s tires which we use for autocross only on our MC. Ran our first autocross day with these recently and the wear on the side walls of the front tires obliterated the first horizontal bars (above the triangles on the edge of the tires) and wore well into the second horizontal bar. Is this too much rolling over on the tire? Do you want to wear a little on the side wall or none at all?

 

I am running Azenis 215s on the 5.5" wide holies and the rollover is a major problem for me. I have pushed the pressures up to 43f and 52r and i notice that they still roll up front. After about 10 events and ~700 miles on the street, the outside shoulders are pretty much bald with the insides still a ways from the wear bars. I can't comment on the performance of the Azenis on anything wider than a 5.5" wheel.

 

2nd horizontal bar looks about right. On the old 215 Azenis, we always ran them down to about half way into the triangle on the shoulder (that indicates where the wear bars are). I wouldn't go any further. Definitely not down onto the sidewall.

Not knowing anything about your competitive driving experience I'll make some generic comments that strongly apply to autocrossing. I'm not trying to be insulting. I've found that many new drivers (I did the same when I started) charge aggressively into the corners and then crank the steering wheel over trying to post a better time. This style of driving is very hard on the tires, and typically not the fastest way to go.

I suggest focusing on turning the steering wheel sooner, but slower, for each element. This allows the car's weight to transfer more smoothly and reduces the odds of the front tires loosing grip and sliding. In slaloms, you should run over the back side of the cones rather than plow into the fronts of them when you do hit a cone. Anyway, driving style has a major impact on tire wear. Smooth is boring but fast. Overly aggressive is dramatic, fun to watch, but slower for most drivers. It's also tough on front tires.

If you're tired of wearing out the shoulder of your tires, you can always install some camber plates and go play in STS! You'ld be amazed at how fun these cars are with some front camber and a larger rear sway bar.

Scott
90SM

 

These are my wheels;
https://www.northamericanmotoring.co...ad.php?t=54801

We have just done 3 & 4 events each so thanks for the advice. At first I was not aggressive enough, but being over so now could be something to watch out for.

 

Rollin, I think you need more tire pressure, too. I ran mine at 43 that day, I think you said you were in the mid-30's? That's too low for a FWD no-camber car on a concrete course, man.

 

I'll start at 40 Sunday and see how that goes. I was at 35. It seemed a bit fare down to me, but somone there said they thought that was about right, so that is why I asked here.

 

Over aggression and insufficient tire pressures can make it worse, but there's no getting around the fact that an HS or GS MINI is gonna be hard on front tires no matter what you do.

 

I can't emphasize how much Scott is "spot on" with regards to many newcomers to autocross. Smooth and steady is what you want. (That ol' "friction circle thing" taught in most Solo2 schools ). Doesn't matter if you're in GS, HS, STS, whatever.

One add'l item of note is track surface: if you run on a concrete pads, that will increase the wear factor immeasurably if you're not smooth. Concrete is like a cheese grater to tires if you're over-agressive.

The car and tires can only perform to their best if you know how to utilize your equipment, rather than abuse it (even if unintentional). Not knowing how much Solo experience you have, it's hard to plug in much advice, but hopefully you are in an area where you can get driving tips and instruction from your fellow competitors to help maximize your fun and raise your driving ability.

 

A pyrometer is a valuable tool also. Tire temps can give you a good idea where you need to be on tire pressures. On FWD cars or cars that understeer,like my old WRX and STi, work to get as much bite as possible up front then adjust the rear to balance the car.

 

Smooth and steady is great but dont forget to drive the limit. Driving the limit will win races. I dont know how many drivers are afraid to push that limit, to do that spin out once in a while, to know that limit. Taking the mcs for example, it already has an understeer given that it is a fwd car, trail-braking would do wonders by getting a severe understeer in the wraps. Keeping the car balanced through turns and a strong traction will keep the driver taking faster turns and could help correct steering problems rather than automatically turning to the wrenches.