A forum for owners of Yamaha TTR250 trail and enduro bikes!

TTRfan · Super Guru

Weird tyre wear!

Markvan · Guru

This is my front tyre wear. The center knob wears towards the rear of the tyre caused from hard braking on tarmac Or any hard surface. Most of my riding is on the road and even the road trail tyres wear like my picture. Im doubling alot so thats 130kg trying to brake down hill on road surfaces wears them odd. If i were to brake hard into a corner they would wear to the side more i reackon. I have been going crazy on the bike alone around a undevolped housing estate with brand new roads. No houses as yet. So its like my own race track. . Its like they wear another one millimeter towards the rear with a few laps with front brakes nearlly pulled as hard as possible. Think i need twin discs on the front. 80 percent front brake 20 percent rear flying into some corners. :).

feetup0 · Member

Brian I've put it down to braking for some reason trials tyres do this, they wear every other row of tread blocks more so on the disc side

TTRfan · Super Guru

Hi Mark and Martin!

I am used to the "braking" wear pattern of every other row of knobbies wearing leaving the alternate row in good condition but this is odd as the wear is different in one part of the tyre compared to another.

Very strange confuse

Brian

brindabella · Senior Member

why do things that wear out, often develop a particular pattern?
for example, a nice smooth new graded dirt road develops corrugations after some traffic.

one tyre wear pattern is due to road camber and driving on a particular side of the road,
one side of the tyre receives more wear (not the issue here though).

another tyre wear pattern is that any particular block subject to either a braking or driving force,
will have a local asymmetry - a "leading edge" effect (not the issue here though).

another tyre wear pattern is seen especially in trials type tyres with square tread blocks in regular lines.
these blocks hammer out a drumbeat (often heard as a buzz on a paved road).
if a wear pattern starts to develop on every 2nd block, it will "resonate" with the main drumbeat,
and will be reinforced, eventually evolving into a clear pattern (not the issue here though).

assuming that the tyre was mounted perfectly and had no manufacturing deformity,
it is still likely (and typical of dirt bikes) that it is not properly balanced.
an out of balance tyre has a lower frequency "drumbeat", once per revolution,
and the force is felt by the rider, and is slightly annoying on a smooth paved road.

so my bet is that the 180 degree wear variation is caused by the tyre being out of balance.
maybe you find the heavy point of the wheel+tyre by spinning it a few times,
and see if it correlates with the 180 degree wear variation.

Chimpy · Veteran Member

The TKC-80 on the front of my mates XT 600 looks the same as that top pic, we decided it was caused by the braking force pulling the knobles over.

matador · Veteran Member

I've noticed this on quite a few tyres, mainly fronts for some reason. I often suspect low pressure but now think it's just a case of some tyres do, call it harmonics of the tyres against the road it shows up more with trail type block tread tyres. Also I've noticed a few times on web pictures 'new' rear tyres with 1-3 centre blocks ripped out, it's not just one make, I'm sure it's the new sharp edge on the tyre gripping too well, & possibly again the harmonics of the tyre as to why 1-3 centre blocks.

Markvan · Guru

More weird tyre wear. Its a front tyre. Arrows point to the low spots and its the same all around, its like that centre knob is not touching the tarmac,( Quantum entanglment) physics.

ttboof · Super Guru

Al the pics look normal but im afraid brian with his only one side of the tire wearing is making my head hurt trying to come up with an answer.

Maybe a bit of a demon on the roundabouts getting the knee down?

-- Edited by ttboof on Wednesday 30th of March 2016 11:02:53 AM

TTRfan · Super Guru

Markvan wrote:
More weird tyre wear. Its a front tyre. Arrows point to the low spots and its the same all around, its like that centre knob is not touching the tarmac,( Quantum entanglment) physics.

Every MX front tyre I have used has worn like that Mark. I was told it was to do with how the tyre acted under braking.

An elderly riding buddy who heard this stopped using his front brake after that to help reduce tyre replacement demands on his meagre pension - and no, he wasn't a Scotsman or Yorkshireman

Brian

PS Yes Les - the wear on my tyre still has me baffled. Haven't seen it before or since confuse

petenz · Super Guru

braking & road camper maybe puting more presure on one side of the tyre....
do your roads have a high crown in the centre ?....

peteBLUEttr · Super Guru

Yes I have had this before, I thought it was road camber hurting that particular tyre but then it did it again on another tyre..