Asymmetrical front tire wear

Hello, for the first time in my life I'm going to have to change the front tire (Avon) before the rear tire...
I've never seen that, even when I was competing! Most of the time I change both tires at the same time (which I'm still going to do because I only have Metzeler available)! There, my front tire has exceeded the limits of the TWI but only on the right side... strange right? Is it due to the cardan, the engine's overturning torque? I wonder...

On my Harley the front tire wears more on the left (Dyna Wide Glide) but since I have the only disc on this side it's explainable whereas the Rocket...
I admit that apart from the overturning torque I don't see any other explanation for this phenomenon!

Do you keep your wallet in your right pocket? The extra weight could account for the wear. Other than that I got nothing.

A tire spinning in air won't wear, it only wears when it's in contact with something, like a road surface. So if the right side is worn more than the left that tells you the right side has been in contact with the road more than the left. It has to be. Now how that occurs is the question. Bike geometry out perhaps?

If only my wallet was involved...I would be very happy!!! That said, according to French users, this asymmetrical wear is simply due to the longitudinally positioned engine. I suspected it a little and I had it confirmed by many users. Now it remains to understand from a scientific point of view because I am eager to know the why and how!

RUN666 said:

Hello, for the first time in my life I'm going to have to change the front tire (Avon) before the rear tire...
I've never seen that, even when I was competing! Most of the time I change both tires at the same time (which I'm still going to do because I only have Metzeler available)! There, my front tire has exceeded the limits of the TWI but only on the right side... strange right? Is it due to the cardan, the engine's overturning torque? I wonder...

On my Harley the front tire wears more on the left (Dyna Wide Glide) but since I have the only disc on this side it's explainable whereas the Rocket...
I admit that apart from the overturning torque I don't see any other explanation for this phenomenon!

Click to expand...

It's probably the camber on your roads. If it's worn more on the right I assume you drive on the left on Reunion Island?
In the UK, my tyres on whatever bike tend to wear more on the right, because we drive on the left. And if you habitually seek out smaller twistier roads they will have have a sharper camber than freeways/dual-carriageways, plus if you're entering turns on the front brake that will accelerate front tyre wear. If you drive on the right and the tyre wears more on the right, that is a bit baffling.

My KTM 1190 has it's tyres changed according to the condition on the front, not the rear. After about 4000 miles the front becomes faceted. If I stand up on the pegs and look down on the front tyre while it is turning and I see distinct flats on the side of the tyre so in profile it looks like half a hexagon I replace the pair.
That's partly how I ride the bike. It's very agile with a centralised mass and I like to brake deep into turns and turn very late because the bike rewards this style of riding. That wears the front as rapidly if not more so than the rear and once that faceting appears the front end loses it's glued-dwon feel and the steering starts to feel sluggish so it's new tyre time. The rear is pretty worn as well by this point but it won't necessarily be right down to the wear bars, but it'll be getting close.
I can't see how the longitudinal torque forces on an R3 could affect front tyre wear.

I think it's down to riding style and road camber. Could also be exacerbated by the Mezteler's compound composition. I don't know whether the Cruisertecs are dual-compound like Michelin R series, or single heat-treated compound like Continentals. The Michelins tend to wear sharply at the join between the harder central compound and the softer, stickier outer. Maybe the Cruisertecs have this charateristic too, and added to the mix of where you ride and how, is contributing to your wear pattern.

Thanks for your feedback Gimlet but in Reunion we are in France and we drive on the right... I can confirm to you, however, that I drive like an idiot and that I put the front tire under great stress at each turn, and there are a lot of them on the island! So I understand that my front tire died before the rear given my driving, on the other hand the asymmetry of wear... apart from the overturning torque I don't see any other reason that would explain this phenomenon. In short, it may also be linked to the Avon because, yes, it is indeed on Avon Cobra (original tires) I will only fit the Metzeler in a few days.

It's probably due to the wheel being offset to the side about 5 mm and the "pulls to the left" effect of the engine causing a commensurate lean to the right by the rider.

Normally, where driving on the right, excess wear is on the left due to longer, higher-speed left turns through intersections (not so much road camber, which is not typically steep enough to cause the observed angle of wear).

Improper suspension setup can also affect your wear pattern. Try increasing your rear shock preload 4 or 5 turns and then back off the rear shock rebound damping to MINIMUM and see what effect that has on tire wear pattern over the next few hundred miles.

When you put fresh rubber on make sure the balance is as good as you can get it. Or try some Dyna-Beads when you change tires and forget the wheel weights.

Some great suggestions already.
I have only one, and that is just too much digging in on the front end during cornering at speed, due to braking in the corner or something like that.
Tyre pressures are in the equation also, as is tyre and road temperatures.
The bike is heavy, The tyres are a soft and grippy as they can be, for that sporty handling characteristics. Go into the corner hot all the time and they can 'step' the tyre pretty quickly.
Question: Do you tend to prefer cornering fast in one direction more than the other? (can be a common phenomenon).

@Einar: "It's probably due to the wheel being offset to the side about 5 mm...":
Seriously? Triumph designs bikes with a non-aligned wheel as standard!!! I'm dreaming...

@atomsplitter:
My rear shock absorber is almost at maximum preload and the rebound is also almost at minimum...
Good idea for the Dyna-Beads, but where can I find this stuff? I don't know anyone who uses this system, have you tried it yourself?

@Jagster:
Objectively, I would tend (being used to off-roading...) to favor left turns, so...

long long time ago i would wear out the right front tire doing you turns to go to yard sales.