Excessive uneven front tyre wear.

[Bonneville63]

Hi

I wonder if you guys have any suggestions...

I recently noticed some extreme uneven front tyre wear on my Bonneville. It's on the front right side.

So far I've ruled out:

Under inflation - I always keep the pressures to the recommended specs in the handbook and have been on sites like triumphrat to confirm the pressures with other users.

The tyres themselves - I recently swapped out the old Metzelers for Avons. The same problem is happening.

Road camber - This didn't happen when I purchased the bike and other bikes along a similar work commute route do not have the problem.

I've not knocked or fallen off the bike and I've kept the chain tension between 20mm-30mm as recommended.

So I'm a bit stuck. It's still within warranty so I guess that will be my last call unless anyone has some suggestions?

Thanks.
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https://www.youtube.com/user/TheBonneville63/videos

[RhynoCZ]

Well, it's rather simple. You drive on the left hand side of the road, which only means you turn right on every roundabout you go through, meaning you put more wear on the right side of the tyre than you put on the left side. We, continentals, have quite the opposite problem.

There is also a possibility, the motorcycle was crashed in the past and now the wheel alignment is wrong, but you'd notice if the fork tubes were bent.
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'87 Honda XBR 500, '96 Kawasaki ZX7R P1, '90 Honda CB-1, '88 Kawasaki GPz550, MZ 150 ETZ
'95 Mercedes-Benz w202 C200 CGI, '98 Mercedes-Benz w210 E200 Kompressor

[Bonneville63]

I understand that as I've mentioned in my post. But it's gotten worse over the last 6 months.

I wonder if that's simply because of the tyres becoming old as well.
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https://www.youtube.com/user/TheBonneville63/videos

[Teflon-Mike]

Pictures may help, but....
You mention that the bike is still under warranty, which prompts a couple of assumptions: 1/ you bought it brand new, 2/ you haven't had it a very long time.
Bought brand-new would tend to dismiss any suggestion of previous owner crash damage, such as twisted forks or bent frame.
New plus short owner span, would suggest that you are still on the hill of the learning curve getting to 'know' the bike... and that for a fair chunk of your ownership, you haven'e ridden the bike with total confidence, whilst observing 'running-in'...
However, assumptions are challenged a little by the suggestion that you have just swapped 'old' Metzlers for new Avons.... I would not expect an air-cooled 60bhp twin, even a relatively heavy 200kg one, to wear out OEM tyres within the warranty period..... So more assumptions to make, either you have done an awful lot of miles, or you didn't trust the Mezlers...
Delving into that arena.... O/H has Avon Road-Riders on her Guzzi... 'old-fashioned' 18" wheels mean they are one of the few tyre choices for such 'classics' and AFAIK they are similarly old fashioned 'Bias Belted' construction.... we got her a new set at Christmas, 'cos the old ones were genuinely 'old'; About eight years going by the date code on the rubber, backed up by a receipt in the paperwork she got with the bike, for them, along with MOT's that implied it had done around 5,000 miles on them... and while the back was a little squared, they still had more than half original tread depth on them!! Few hundred miles 'in' on them, they are looking nicely scrubbed in, but hardly worn at all...
WHICH makes me a little surprised you can even see significant 'wear' on relatively new tyres, let alone uneven wear....
Does chuck up another query though... you say Avons.. not which ones. As said, road-riders AFAIK are bias belted, but specs for the 'new' bonnie suggest that it takes radials... Avon offer the 'Cobra' range for cruisers in sized to suit, which I think ARE radials, BUT.. the Road-Riders cover the same sizes in Bias-Belted....
So have you fitted the 'cheaper' bias-belted tyres in place of radials?
But, follow on, thoughts, suggest it's more likely to be your riding, than any inherent fault in the bike....
Bonnie, aping the original, has geometry and dynamic more akin to a cruiser; weight bias is to the tail, it responds to 'balenced' braking, with more rear-brake effort, and wont like either hard front brake or trail-braking into corners too much.
As your confidence in the bike has grown, are you riding it much harder than you were?
Next, are you 'trail braking' into turns, particularly slower tighter ones like smaller round-abouts?.. Do you KNOW whether you are trail braking? Could you be 'lagging' coming off the front brake, before getting on the throttle to 'drive' it through such turns, or even, 'accidentally' dragging the back-brake, as you lean it in?
But, that bike has a big front wheel, and relatively a long'ish wheel-base and a lot of fork rake; At full steering lock, the front wheel 'leans' quite a lot relative to the back, with a lot of 'offset' from the quite large 'trail' of the big wheel; so it would prefer to get its turning from 'lean' rather than from steering the handlebars.... but, back to those tighter, slower turns like round-abouts.. chances are, you use more bar lock and less lean, so even without any braking effect, you get a 'hesitancy' in the mid turn, where it doesn't feel 'right' getting on the throttle to 'drive' through, after you have tipped in, because you haven't really 'tipped in' so much, and with so much steering lock 'on' it still feels like its not really turning, which results in you going round a lot of the turn, with the front wheel tilted more, and off-set more, to the back, 'pushing' creating more 'scrub' between the tyres, that will be made worse, as you try and push the bike round with a little throttle, and are likely to apply even more bar lock to counter that seeming to try and push the bike wide... the result being you feel that 'scrub' from the bar-lock created off-set, and apply even more of it, as you apply more throttle... AND that is most likely ON right hand round-abouts.. bringing us back to that "we drive on the left" suggestion... but, excaserbated by the bikes nature and your riding style.
If there is real differential wear on the front... I suspect that these are likely causes.
You might not notice any change to the wear pattern in a hurry, but, I'd suggest you look at your riding style, and think about how THAT might have changed since you have had the bike, and I might suggest, you try the 'counter-leaning' technique. On slower-tighter turns, get the bike to turn by tilting, lean the bike more, and use less handle-bar lock to make it go round, and where that feels 'wrong' because you dont have the g-force to support so much tilt, rather than leaning over with the bike, or leaning your body further than the bike, lean your body less, and the bike more, keep your head and shoulders 'up' and let the bike tilt between your legs.... more like a dirt-bike style... you should find that it'll tip in a lot more hapily, and if anything I have said about that 'hesitancy' and the tendancy to try and run wide mid turn rings true.. that should become less pronounced, as counter-leaning reduces the amount of 'off-set scrub' keeping the wheels more in-line with the forces, making it track more naturally, with throttle 'driving' the bike through, rather than fighting the off-sets, and creating that front tyre wear.
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My Webby'Tef's-tQ, loads of stuff about my bikes, my Land-Rovers, and the stuff I do with them!
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[Pete.]

Wheel misalignment would have to be extreme to do this on a bike. It's not like a car where you can have excessive toe causing the tyres to work against each other. On a bike if the wheel isn't pointing dead ahead then the bike won't ride straight and any adjustment is automatically adjusted by the rider.
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a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[mentalboy]

[iooi]

[Teflon-Mike]

[mentalboy]

[Teflon-Mike]

[iooi]

[RhynoCZ]

When I was commuting, the round about was the only place where I got the peg on the tar. Some of the round abouts here are huge, so going more left (right in your country) puts more wear on the left (right in your country) side of the front tyre.

Check these pictures, the left side of the tyre is gone...
https://i970.photobucket.com/albums/ae184/RhynoCZ/GPz550/Image1291.jpg

https://i970.photobucket.com/albums/ae184/RhynoCZ/GPz550/Image1292.jpg
____________________
'87 Honda XBR 500, '96 Kawasaki ZX7R P1, '90 Honda CB-1, '88 Kawasaki GPz550, MZ 150 ETZ
'95 Mercedes-Benz w202 C200 CGI, '98 Mercedes-Benz w210 E200 Kompressor