Frustrating Cup tyre wear

[mr wilks]

A lot of stuff not relevant to this thread

Do you have to? Of course cups are not going to be the "right tyre for longevity" that's not really the op's point, it's a question about excessive inner tyre wear, not about what type of tyre or what 'most' people on the forum do. Sorry but it just gets my goat people commenting on things they don't really get.
Sadly sixspeed, I can't help that much but could it not be the case of running somewhat severe negative camber whilst using the car for road miles? With the intrax setup on my last car it was a cinch to adjust the camber when arriving at track and then back to -1 or so when finished.

Sixspeed has posted he is at a loss as to why his tyres have worn so fast & on the inside edge , i can't help him with the uneven wear , il leave that to GEO experts like yourself ,
At the end of his OP he was questioning whether or not they were the right tyres for him going forward & i was merely pointing out that Cup tyres are not ideal for doing 95% motorway miles with a few hundred track miles thrown in

 

[mr wilks]

please only comment on technical posts if you have a modified car

Have you considered asking the mods for a specific section where only those that have modified their cars can discuss topics ?

 

[TomK]

I thought inner tyre wear was a trait of ZMs ? married with a predominantly track focused tyre & the ending is pretty predictable :?

I'll just leave that there in case you do a Jb on us
Seriously though, as I've clearly stated I am no "geo expert (sic)" and have given what little helpful advice I can I shall be going to bed!

Perhaps the mods could set up a separate 'modified rims' section for you so you don't feel left out...

 

[mr wilks]

I thought inner tyre wear was a trait of ZMs ? married with a predominantly track focused tyre & the ending is pretty predictable :?

I'll just leave that there in case you do a Jb on us
Seriously though, as I've clearly stated I am no "geo expert (sic)" and have given what little helpful advice I can I shall be going to bed!

Perhaps the mods could set up a separate 'modified rims' section for you so you don't feel left out...

Staggered at times by some folks who previously come across as rounded then suddenly show up as a complete knob .
Goodnight Tom , your mum will be in shortly to tuck you in as sopn as she's finished making your packed lunch up

 

[exdos]

Sixspeed,
Driving on motorways (essentially long distances in a straight line) with increased negative camber means that the contact patches on the tyres are loaded more on the inside shoulders than equally across the full width of the tyre. In this scenario negative camber is unnecessary. Likewise, when travelling in straight lines, there is no need for any toe angle, and toe-in with negative camber will cause "scrub" of the inside shoulder. The Cup tyres confer high levels of grip because of their soft compound rubber. Consequently, your geometry, soft rubber and lack of cornering to equalise wear, have worked against longevity of your tyres.

I understand that motorcyclists travelling from the UK to The Ring can also ruin their tyres by the long motorway trip, wiithout cornering, because the 500+ miles of travelling in an upright position of the bike squares-off the rounded tyre profile.

Geometry setting is a compromise in anticipation of the intended performance of the car. You have used a track setting yet only needed it for 5% of the actual use hence the unequal wear.

Adjusting front toe can be a doddle provided you can easily undo the nuts for the tie rods. You just need to know how many degrees of toe you get with one turn of the tie rod. All you need is an18mm and 13 mm spanners.

 

[original guvnor]

Were your tyres the Pilot Sport Cup + or the newer Cup 2's? You've probably already read this -it's Michelin's blurb on the Cup 2 - but it does mention details on the contact patch and the new compounds used on inner and outer edges

http://www.michelinmotorsport.com/content/download/8715/152333/version/2/file/MICHELIN+Pilot+Sport+Cup+2_EN.pdf

 

[FR08MEE]

I had a similar experience with the first set of tyres on my M and when I eventually took the car to the alignment centre (who are pretty well known) I was told that it is likely to be the toe-in coupled with the negative camber across the front.

As a result I got all of the toe-in removed and the wear on the inner shoulders improved dramatically... My car has started "scrubbing" the inside edge and doesn't feel as balanced again so I need to get the alignment done. I think our cars are really sensitive to alignment when it comes to handling and I think it's reflected in the type of tire wear that is seen when the allignment is slightly out or not "ideal".

My car is used on the road but like I said I think the weight over the front, toe-in, negative camber and straight roads = scrubbed inners this will be worse if the allignment is out

 

[sixspeed]

Usually my Z sees nearer 75:25 track:road use these days, but obviously this road-trip was an exception. I didn't expect such abnormal wear on the Cups though as a result.

It is going in next week for a check-up on all the suspension components. Will keep this thread updated..

 

[Beedub]

Not sure if you meant Beedub, me or both. Mine probably sees 50:50 track : road miles these days but previously I ran OEM / Eibachs for 30k+ miles with 90% on the road.

Very few M owners will see anything like 50-50 road track so tyre wear will obviously reflect how the miles were covered :?
If mainly road use i wouldn't think Cups were the right tyre for decent longevity
In regards your own question above to Beedub on tyres wearing evenly for most of the forum they maybe think the question relates to everyday road use ?[/quote]

id say i see around 60 % road 40% track work, more track work depending on how many holidays i have booked :evil: :evil: :evil: :evil: :evil: As the OP commented on his car being a track biased vehicle with a total track biased suspension setup i was referring to mine and his wear comparison, when my car was completely stock i used to find the tyre wore very evenly and if i did track work the outer edge would suffer/ overheat.

i ran the old cups on my CSLs and found them to wear very quickly whch soon translated to me not being able to afford the upkeep, hence the shift to the 18s to get a much broader range of tyre cheaper, this was a very good choice !

In this case i think you've ran a few more miles thats killed the inner edge ( based on your neg amber setup) , if you do a few hard track days i think you'll find this evens out nicely., as this type of driving as you know hits the middle and mostly the outer sections of the tyres ( usually why the semislick tyres are a different tread pattern on that outer edge)

 

[abar121]

Not sure if you meant Beedub, me or both. Mine probably sees 50:50 track : road miles these days but previously I ran OEM / Eibachs for 30k+ miles with 90% on the road.

Very few M owners will see anything like 50-50 road track so tyre wear will obviously reflect how the miles were covered :?
If mainly road use i wouldn't think Cups were the right tyre for decent longevity
In regards your own question above to Beedub on tyres wearing evenly for most of the forum they maybe think the question relates to everyday road use ?

id say i see around 60 % road 40% track work, more track work depending on how many holidays i have booked :evil: :evil: :evil: :evil: :evil: As the OP commented on his car being a track biased vehicle with a total track biased suspension setup i was referring to mine and his wear comparison, when my car was completely stock i used to find the tyre wore very evenly and if i did track work the outer edge would suffer/ overheat.

i ran the old cups on my CSLs and found them to wear very quickly whch soon translated to me not being able to afford the upkeep, hence the shift to the 18s to get a much broader range of tyre cheaper, this was a very good choice !

In this case i think you've ran a few more miles thats killed the inner edge, if you do a few hard track days i think you'll find this evens out nicely.

Spot on!

 

[ga41]

I've been driving mine with 0 toe front and rear for a few thousand road miles now and i've noticed much more even wear than before on my Yokohama AD08s... I think toe affects inner tire wear more than a small degree of negative camber...

 

[FR08MEE]

I've been driving mine with 0 toe front and rear for a few thousand road miles now and i've noticed much more even wear than before on my Yokohama AD08s... I think toe affects inner tire wear more than a small degree of negative camber...

+1 this is what I stated above and is probably the likely cause.

 

[sixspeed]

I'm leaning towards the toe settings also (although 0.2mm - if it was set correctly, is near-as-damnit neutral)...

I'm not convinced by camber as I've run serious camber on many tyres in the past and the wear comes out more like this:

and is typical of camber-based wear.

^^ This kind of wear is toe-related, and looks more like the wear on my Cups. But I'm struggling with the fact that 0.2mm of toe-in (about 0 deg 1' !) caused this.

In my mind, it was either set incorrectly, I hit something that knocked it out early on in the trip (but fairly certain I didn't!), or there are some worn suspension components somewhere causing play. I guess I'll find out the answer to most of that next week.

 

[ga41]

Did you get to the bottom of this?

 

[Argenta]

Sorry saw this thread just now.
Try 1mm toe in at least. I think that will sort it, but of course you will always get a LITTLE more wear on the inside with 2deg camber.