Okay, I've got a fresh set of Kumho MX's coming in for the second half of the autoX season and the question I'm wrestling with is whether or not to get them shaved or just get them installed and put some miles on them since I have a month before the next event. Any thoughts, suggestions? I've heard that the Kumho's don't get fast until they're down to 4/32's of tread depth but at the same time knocking off almost 60% of the tread is kind of scary. Thanks.......On another Kumho subject, anybody running these have a recommendation on what tire pressures to start at or is it just the same as the Advans.

 

Personally I would just puts some miles on them since you do have a month until the next race.

 

I have Kumho's and the dealer reccomended 39psi in the front and 25psi in the back.

 

For autocross, at least go to 42psi (hot) on both front and back. Some of the more experienced racers here have said they go up to 50psi (hot). I personally go higher in the rear, since I have no suspension mods, because that helps the rear end rotate. I'm not sure what the MX's are, but I have the Ecsta V700 (R compound).

 

Shave if you want to win.

 

If you are running local events, (not bigger divisional and national and all) then dont worry about shaving them, you should be able to win anyway, if not, drive faster

There is some merit to shaving for longer life actually, some tires have a tendancy to tear themselves up a little more because of tread blocks, I am not sure about the MX. I think Tom Hoppe did well on "naturally shaved" MXs in his National Championship STX WRX. Naturally shaved being driven at locals till they were worn down.

Pressures, I haven't been on them other than fun runs and such, but I would start at 38/38 cold and go from there if i was going to start trying pressures for autocross.

Jon K
www.seat-time.com

 

Thanks for the insight everyone. I think I'm just going to mount them up and have it. That was the info I was looking for Jon so I appreciate it.

I typically run the Advans at 40 in the front and 42 in the rear to get the back end to rotate a little better so it sounds like Kumhos will be similar. Thankfully I have a test and tune day prior the next event.

 

Tom Hoppe from NC? He won a national championship in a WRX? Wow, if it's the same guy, holy crap. We used to have some knock-down drag-outs at Rockingham Raceway when he was still on the 14b with both of us running 12.2s or so. Of course, we were just fighting for 2nd place behind Al Blaha and his high 10s...

 

Don't bother shaving them, the MXs aren't really R-compound tires ... just drive them and get the initial coating off and you should be good ... Keep the tire pressure above 40psi if you are auto-xing ...

 

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