[kevinb99]

Avon Storms with 8500 miles on them.
Run at 42psi ( as recommended)[attachment=19516:Reduced.jpg]
I know thats a good milage but has anyone ANY idea what is casing them to wear like this?
This is the second time out of four sets of tyres, the bikes were different.[attachment=19515:reducedTyre 2.jpg]

[ajoe90]

relaxed, on 08 August 2010 - 08:21 AM, said:

Easy. Set the back wheel vertical by adjusting the bike on the centre stand and a spirit level or plumb bob against the back tyre. Then turn the handlebars so the front is vertical too, again using the level. If everything is aligned properly the wheel alignment will be correct looking along the bike. A straight edge or tight string or laser line will show the same distance between the side of the narrower front and the rear on both sides.

If you have twisted forks, for example, you won't get the wheels aligned both vertically and horizontally. The rake of the steering head causes the front wheel to move off vertical as it deviates from straight ahead.

I hear what you are saying, but what you are doing is setting the bike up vertical so that you can check wheel alignment and how you are checking that is what I would do. Having said that, there is no adjustment for vertically aligning wheels, the front spindle is not adjustable on bikes and the rear is only adjustable from left to right when looking from the front or rear of the bike. If you have bent/twisted forks or forks not aligned in the triple clamps, that's a whole different issue.

Not being arsey with you mate, just having a discussion on the mechanics of stuff

[relaxed]

ajoe90, on 08 August 2010 - 01:29 PM, said:

I hear what you are saying, but what you are doing is setting the bike up vertical so that you can check wheel alignment and how you are checking that is what I would do. Having said that, there is no adjustment for vertically aligning wheels, the front spindle is not adjustable on bikes and the rear is only adjustable from left to right when looking from the front or rear of the bike. If you have bent/twisted forks or forks not aligned in the triple clamps, that's a whole different issue.

Not being arsey with you mate, just having a discussion on the mechanics of stuff

OK, I see my original reply was ambiguous. I was just trying to show a way the OP could see if his frame or forks or swing arm were misaligned. Misalignment might cause tyre wear like he showed in his pictures.

[kevinb99]

Just had a reply from the Avon techies so I thought I'd give you the professional opinion---


Hi Kevin,
Cupping can often be observed on front tyres that have been put under a
high load. There are many reasons for this phenomenon including bike
geometry, weight, suspension, cornering speed etc. The most common cause
is that where ever there is a groove in a tyre, there will be more tread
deflection in that area of the footprint as the tyre rotates. The areas
of the footprint in-between the grooves take the tyre loading and hence
wear more in those areas. This can lead to irregular wear/cupping.

I think that as you ride two bikes that can easily load up a front tyre,
the fact is that after 8000 miles, the tyres are just worn out. Believe
it or not but this shows that you are riding the bike correctly through
the corners.

Best regards,

Peter J McNally

M/C Technical Product Manager

01225 357753

www.avonmotorcycle.com



seems like it's just me being mean and getting the last out of the tyre!

[plato]

Happens to all of my front tyres,is normal,looked it up once and got an explanation which i cannot now remember,but tis normal enough,as for people "not knowing sometimes",theres experts everywhere

[K Kid]

I always ask - what tyre does the tyre manufacturer recommend for the bike??

Ask the tyre company for an opinion - they ought to know !

http://www.avon-tyre...=showtyre&id=25

This post has been edited by K Kid: 25 August 2010 - 09:36 PM

[danceswithmopeds]

It's because of the camber of the road. If you had ridden those miles on mainland europe, the wear would be on the other side of the tyre.