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

Sparky · Member

Michelin Enduro Comp4

TTRfan · Super Guru

Hi again Mike!

The Comp IV is my front tyre of choice and I have not had a problem such as you describe.

It sounds as though you are an experienced dirtbike owner so I am at risk of telling Grandma how to suck eggs here

Check:

Wheel bearings are good with no play and that the wheel runs true between the forks with no more than 2mm run out on the rim.
Steering head bearings are good with no notchiness or play.
Fork leg seals and bushing are good with no leaks and no play in the bushings.
The tyre is perfectly seated on the rim and that it is reasonably balance with the tyre clamp opposite the valve.

If the TTR passes all the checks then you may have to consider the possibility of a defect in the tyre.

Brian

Sparky · Member

Thanks Brian, I won't get a chance to fiddle with it until the weekend now, but as the problem only really manifested itself when the tyre was changed I'm guessing it's tyre related. Can I ask what pressures you typically run?

Mike

peteBLUEttr · Super Guru

I just run 14 lb psi in both front and back all the time for road and dirt. It wouldn't be because of a particular brand/model/style of tyre I wouldn't of thought, so yeah just check all your bits and bobs at the front of the bike and see what you can deduce. Where abouts do you go riding in the alps?, sounds great fun.

TTRfan · Super Guru

Because the front is more susceptible to compression punctures (or "snakebites") I tend to run it at about 18lbs and the rear at about 14-16lbs depending on time of year and type of going.

Brian

Sparky · Member

peteBLUEttr wrote:
I just run 14 lb psi in both front and back all the time for road and dirt. It wouldn't be because of a particular brand/model/style of tyre I wouldn't of thought, so yeah just check all your bits and bobs at the front of the bike and see what you can deduce. Where abouts do you go riding in the alps?, sounds great fun.

They're old military roads around the French /Italian border Briancon, Sestriere that sort of area. 7,000 to 10,000feet, the scenery is fantastic, but the old bikes and the old blokes can run out of breath at altitude!

Sparky · Member

TTRfan wrote:
Because the front is more susceptible to compression punctures (or "snakebites") I tend to run it at about 18lbs and the rear at about 14-16lbs depending on time of year and type of going.
Brian

Thanks, that's about what I was running. After years struggling with milk crates I've got a proper bike lift coming this week so I'll get the front end properly off the ground and see what's going on.

Mike

comeragh · Senior Member

Sounds unusual .
Have used mitchelin ecs for years with no problems .
Great tyre all round .
The only 2 issues are they can take alot of pressure to bead out correct and the front when used alot on roads can wear of at the edges before the center .Must use a softer compound for cornering grip .

Try breaking the bead and beading it in again .

Sparky · Member

comeragh wrote:
Sounds unusual .
Have used mitchelin ecs for years with no problems .
Great tyre all round .
The only 2 issues are they can take alot of pressure to bead out correct and the front when used alot on roads can wear of at the edges before the center .Must use a softer compound for cornering grip .

Try breaking the bead and beading it in again .

That's on my to do list plenty of tyre soap and wind up the compressor. The tyre seems to be seated evenly round the rim, but I had the front off the ground last night, wheel and head bearings seem ok, nothing obviously wrong with the forks, there's no rim run-out and the wheel alignment seems ok, so running out of options!

TTRfan · Super Guru

Unlikely but defective tyre?

Sparky · Member

TTRfan wrote:
Unlikely but defective tyre?

Might come down to that Brian but as you say unlikely with a quality firm like Michelin. I'm going to look at the suspension settings as well, sometimes a weird harmony can set a terminal weave off. I've had a couple of really bad tank slappers on road bikes that I'd done a lot of miles on with no problems then one day a combination of load and weight distribution unsettles them and they try and spit you off, tweaked a few things and it never happened again but it destroys your confidence for a while!

Mike