Uneven Front Tyre Wear

[jeremyc]

I'm noticing much greater wear on the inner edge of both of my front tyres. A geometry check shows that nothing was wildly out, so:

1. Any one else experiencing the same problem?
2. How far out would the front geometry have to be to cause uneven wear?
3. Anything else that could be causing it?

[Ruckie]

Thats spooky ! Just been looking at tyre prices. Inside front tyres almost bold ,outside looks almost unused. Apparently tracking, but like yourself need to know if this is a common problem.Could work out expensive if ongoing problem.

[VYT]

Mine wears the offside edge of both fronts. Probably due to excessive cornering speed on motorway off ramps.

[vroom]

And mine too.

If its wearing on the inside & tracking is OK it must be camber.

You can get excessive camber if your springs are too low (sagging) or if you have adjustable ride height that again is too low.

Mine was due to the latter. Increasing the ride height corrected the camber.

Its all to do with trignometry I suppose.

Nick.

[ATG]

Don't know how similar the Cerbera geometry is to that of the Chimaera, but I was concerned by the same thing happening to my front tyres. MOT geezer said I needed the tracking checking, so next time I had the car serviced I asked Dave Batty to check out the geometry. He said the car was set up fine and the apparently "excessive" tyre wear was normal. It's a compromise between handling and tyre wear. The SO2s on the front of my Chim were pretty much bald on the inside and had at least 2mm left on the outside.

[FourWheelDrift]

Could it be anything to do with the steering rack?

Only getting the wear when you turn the wheels, thus the rack is adding camber and wearing the tyres on the insides.

Never known this to happen, just thinking out aloud.

[aaandy]

Do you do a lot of track days? Even if your set up is OK, hard cornering on a track can wear the inside of the tyre. Happens where the inside edge of the front tyre is scapped side ways across the track.

There is a section about this in Steve Heath's Chimaera/Griffith bible (mine is version 2 of the bible). Guess that the same priciples would apply to your cerbie.

Hope that this helps.

[rocket]

I had the same problem. It resulted in the front tyres not lasting any longer than the rears (about 10k miles). The dealer said that there was nothing wrong, it was just the way the suspension is set up...basically, TADTS. (Mines an early '98 on standard 16"s and suspension.)

Neil

[deanpluthero]

Jeremy, mine had this problem.. thought it was tracking at first, which they did; then within a 1000 miles it had stripped the tyres on the inner side (leaving the rest of the tyre unused.
It turned out to be my shocks.. so get them checked (they're covered under warranty) hence i got the adjustables

Dean
www.theratpac.com

[deanpluthero]

btw Jereemy have you seen the other cerb going up and down villiers road.. same colour as yours W reg haven't fiqured who it is yet... thought it was you at first.. that makes 4 on villers road.

Dean
www.theratpac.com

[jeremyc]

Thanks all; seems that Cerberas all suffer from it to a certain degree with the general suspension setup to blame.

I have only done one track day (plus a few runs up and down Bruntingthorpe ) so it is probably road use that has worn them. They have lasted 18K miles though, with plenty of tread on the rest of the tyre. My friendly Tuscan Challenge driver at the dealer of course diagnosed it as "too many trackdays".

[joospeed]

Jeremy .. excessive inner edge wear is caused by a fault .. you don't get inner edge wear from camber alone .. you can run 3deg neg camber with no ill effects if the toe is set 0.5deg in total.
Most common fault is the front springs sagging .. the cerbie gains toe out with suspension going into bump, so you gain camber (not too bad) but also toe out (big no-no). For this reason the steering MUST be checked every service and adjusted.

[jeremyc]

Thanks Joolz: latest check revealed no significant problems, so I can only assume that it has been out at some point in the past.

Check showed a total of 0deg27' toe which looks to be about correct. It could as you point out be due to this changing under bump. How is your Nitron & spring stock looking?

[jeremyc]

deanpluthero said:

btw Jereemy have you seen the other cerb going up and down villiers road.. same colour as yours W reg haven't fiqured who it is yet... thought it was you at first.. that makes 4 on villers road.

Seen it around Dean; in fact I stood behind the owner in the dry cleaners the other day without knowing it (until he drove up the hill) - D'Oh!

Still not sure who it is though....

Edited to say: could be sixx

>> Edited by jeremyc on Monday 28th July 17:49

[joospeed]

jeremyc said:

Thanks Joolz: latest check revealed no significant problems, so I can only assume that it has been out at some point in the past. Check showed a total of 0deg27' toe which looks to be about correct. It could as you point out be due to this changing under bump. How is your Nitron & spring stock looking?

that figure does indeed seem spot-on, so conclusion is that the tyres have been wearing abnormally in the past and even though the steering is correct you can't compensate for any previous wear.
Nitrons .. you still wait about 4-6 weeks for these, they're selling like hot cakes from the hot cake shop.