Asymmetrical front tire wear

[Dr.D]

The front wheel and tire are offset by design by the manufacture. It is done to compensate for the torque, weight and design of the rest of the bike. It does not promote uneven tire wear. It actually prevents it and causes the bike to track more straight. The tire wear pattern you have is caused by another factor.

 

[atomsplitter]

The front wheel and tire are offset by design by the manufacture. It is done to compensate for the torque, weight and design of the rest of the bike. It does not promote uneven tire wear. It actually prevents it and causes the bike to track more straight. The tire wear pattern you have is caused by another factor.

Sounds like it's time to call Hinckley and get a definitive answer. Anyone got their number (and willing to make the call)?

 

[Kiwicol]

I think Jagster lives close by the factory, maybe could go in & ask?

 

[Jagster]

I think Jagster lives close by the factory, maybe could go in & ask?

Not that near, but if and when I next go to the visitor centre, I will try to ask to speak to somebody......don't hold your breath though.

In the meantime, anyone who can't wait that long can call them directly:


Triumph Motorcycles,
Normandy Way,
Hinckley, LE10 3BZ
+44 (0)1455 251700

 

[RUN666]

Ok. But it's not clear to me how you are able to conclude that those particular differences result in the steering geometry being out of alignment.
Surely you would need to take a line from the centre of the front and rear tyre (or rim) and reference from there to the centre of the axis of rotation of the headstock.
If the headstock axis is offset (in plan view) to the centre of the wheel rims when they are aligned with each other, then you could state that the bike has an offset, but it's a very difficult thing to measure, so i'm somewhat doubting your conclusion.
You might be right, but then again.......
I'm not suggesting that you just noticed the front mudguard being out of alignment with the tyre and declared the chassis as being out of alignment, but I think there's is more to this than what we have been discussing earlier in the thread.
I have to confess that I had noticed the mudguard offset etc.. before, on my bike about a year or so ago, when I was making my front fender extender, but I kinda just accepted it and then forgot about it.

Every shaft drive bike i've ever owned looked like it had some offset at the rear wheel, but i've never investigated it to any extent because it's difficult to do with any accuracy. Perhaps this kind of thing is more common than we are aware???

I conclude that the steering is not centered simply by noticing the asymmetrical wear of the tire... Add the engine's overturning torque to this difference and the explanation for this wear seems obvious to me. Afterwards it is very possible that the wheels are aligned in the longitudinal plane, or not, but I do not have the material means necessary for this verification. Now I make do with it like you with the mudguard and I would change my tires more often...

 

[Dr.D]

I did not call the company but when the new bikes came out my mechanic went to a week long school for the new bike. It was this mechanic that gave me the information.

 

[Renigma]

As you said, it's by design- all of our front wheels are offset on the 2.5s.

As far as wearing on the right, and this may contradict what someone said earlier about driving on the right side of the road, I was told by a mechanic years ago with my '98 Thunderbird Sport that this is normal due to our right turns being sharper than turning left.

What I suspect on the 2.5s is that the way it always wants to drift left (evident if you take your hands off handlebars) forces you to constantly apply just a slight amount of right turn pressure to compensate. This constant steering pressure to the right wears the right side of the tire more than the left. That's my theory and I'm sticking to it

Static balance on front and dynabeads in the rear

I think this is the best explanation.
My bike goes to the left when I take my hands off. I've also observed that the bike leans slightly towards rights when going straight to counteract the left going tendency. I gave my bike to brother and rode behind to observe this on multiple occasions and different roads. And that's why my front tire is quite clearly worn out more on the right side. The rear looks okay though. Seems completely symmetric.

 

[eka]

I think all my bikes has worn tires more at right side...not just Rocket with wonky geometry and longitudinal engine. At right side traffic if you stay at yours side, the corners are tighter to right as you are at inner circle and left turns are at outer circle.

 

[Kiwicol]

This uneven wear on front tires has always been a bit of a mystery, never have I found a definitive reason for it. Eka, how does that stack up for those of us that ride on the left? It doesn't.

Couple of absolutes to bare in mind while considering this issue:
1) a tire spinning in mid air won't wear down the tread
2) tread only wears when a tire is spinning and in contact with a surface
3) load on the tire whilst in contact with a surface will affect wear, greater load = greater wear

The question is how do we spend much more time on the right (to cause accelerated wear on the right side of the tire) than the left?

For those of us that ride / drive on the Left, you can make the argument that our right turns at intersections are longer, 3 times longer actually than a left turn (because they are) and that our right hand corners on the open road allow better visibility throughout the turn than a left hand one does, hence we could assume because of the better visibility we tend to take the right hand corners faster - faster = more load and lean which = more wear on that side.

All this 'sounds' reasonable until you go to a country that rides / drives on the right lane, these countries should therefore have greater wear on the left, but they dont! They have the same wear on the right, so all the above (except the first 3 points) goes out the window.

I've also read that it's the road camber that does it, nope, the camber if the road is insufficient to cause this issue & why don't cars get it then? & why is it not opposite for right hand drive countries? Actually I'd like to hear from someone who lives in Germany and rides the Autobahn, do they also get the accelerated wear on the right?

Maybe it's voodoo built into the bikes by the manufacturer to drive us all crazy . . .