New tyres chipping on the edges...? why?

[powerman15]

Hey guys,

I've done about 2000km on my new 285s Cooper STMaxx's...? and they appear to be chipping on the edges....

anyone have any ideas?

I'm running 30psi in fronts and 32psi in the rears... used the 4psi rule to come to these figures

I've been up the powerlines, over plenty of rocks on multiple 4wd tracks.. but still wouldn't have thought it'd chip the tyres that bad???

[WHHEMI]

Did you air down when off road, if so what pressure did you drop to.

[powerman15]

Originally Posted by greenjk

Did you air down when off road, if so what pressure did you drop to.

I usually do, but the last couple times I haven't because I thought 30psi isn't too bad for fast rocks.. I know if I was rock crawling very slowly i'd drop them to 25-26ish?

but travelling over rocks at 20-30kmh i thought 30ish was okay? maybe not?

[WHHEMI]

Maybee not, it depends on the tracks you do, but over here I normaly air down to around 25psi for high speed dirt 60/80kph any thing slower or rougher than that and I go lower somtimes as low as 15psi or lower if stuck and on the soft sand in NSW 8/10 psi, and I havn't had any chipping with 110,000k on BFG AT's and 25,000k on BFG KM2's.

[powerman15]

Originally Posted by greenjk

Maybee not, it depends on the tracks you do, but over here I normaly air down to around 25psi for high speed dirt 60/80kph any thing slower or rougher than that and I go lower somtimes as low as 15psi or lower if stuck and on the soft sand in NSW 8/10 psi, and I havn't had any chipping with 110,000k on BFG AT's and 25,000k on BFG KM2's.

wow that is low. in sand in WA i'm at 17-18psi and it gets through nearly everything... if stuck I go as long as I need to..

but okay, mite try go down to roughly 22ish for rocks and tracks now if i hear a *hissing* sound i'll be hunting you down greenJK! haha

[WHHEMI]

No problem mate, you could try talking to some of the locals to see what they run, as the tracks are very different over there, also if the chipping is only on the rear try selecting 4 high next time and see if this helps.

[powerman15]

Originally Posted by greenjk

No problem mate, you could try talking to some of the locals to see what they run, as the tracks are very different over there, also if the chipping is only on the rear try selecting 4 high next time and see if this helps.

yeah hoping some locals will see this thread...

also, the chipping 'is' only on the rears! why would 4 high help this...?

as up the powerlines in wa, most of the track and hills are done in 4 low..