How important rear tyre balancing?
 

How important is it to balance the rear tyre on an XT? Bike does a max speed of 80mph on Motorways. Thanks

I always balanced both tyres back in the sixties, in those days it cost nothing as most bike came with adjustable balancers. I also balanced the tyres on my BMW and Enfield. If they are unbalanced it will wear the suspension and transmit an irritating vibration throughout the bike and you. Vibration will also cause your luggage to rub and chafe.

Hi,

So far i never balanced my tires...not on my XJ900, not on my NTV before and never on my transalp. No problem up to 200 km/h.

LG, Tobi

It depends! Some bikes seem to be more sensitive to out of balance vibration than others. How out of balance is it? Is the front balanced or not?

My rule of thumb with my current stuff is that +/- 10gms is good enough. I start to notice it at about 30gms - particularly on the front, and if both front and rear are out of balance by about that much or more it sets up an in and out of phase resonance (front and rear wheels are diff sizes so revolve at diff rates) that can get to the point where it snaps things. Some years ago I had really unbalanced front and rear wheels on my CCM - somewhere round about 70-80gms each (the weight of the rimlock). It was unnoticeable up to about 55mph, got annoying as it went in and out of phase at around 60-65mph and by 75-80mph was giving me double vision. After about 50-60 miles on the motorway the vibes snapped the silencer mount. A couple of hours playing with strips of lead taped to the spokes fixed it and I've not had a problem since.

I'm doing a trip to Portugal in a couple of weeks and my rear tyre won't get me there and back, 3mm left on a TKC80. I was just trying to decide whether to change the tyre before I go and get it fitted/balanced professionally, or whether to strap a tyre to pillion and change by hand when I get there. I'll be staying on a farm about 50kms from the nearest tyre dealer, so getting it fitted & balanced professionally whilst I'm there isn't an option.

The front has 6-7mm left on it and was professionally fitted an balanced, so that should still have life left in it for the return trip.

The rear was professionally fitted and balanced, but with new rubber if there is a significant imbalance it will be on a different spot on the tyre, so that means nothing.

I guess another question would be, if you take the chain off the rear sprocket so nothing is holding the wheel still, can you balance the wheel on the bike, or will the wheel not turn freely enough on it's wheel bearings, for the heavy spot to rotate to the bottom and expose the imbalance?

This.....

‪How to Balance a Motorcycle Wheel‬‏ - YouTube

Can I do that on the road without the equipment, by letting the wheel rotate on the rear spindle? Or would there be too much resistance?

It depends on the bike. A centre stand makes it much easier.
taper bearings tend to be a little bit tighter than ball bearings.
sometimes the brake can be binding slightly. it is easy to push pads back a tad for a moment or two if they are.
and if you had a shaft drive the gears would also tend to bind a little.

I have never had a problem testing and balancing my wheels, but most of my bikes had spoked wheels which are much easier than cast ones.

Ralf, if nothing is giving you problems at the moment and you're just changing the tyre for something similar I really wouldn't worry. There are heavy and light areas in tyres but we're only talking small amounts. If your front wheel is balanced and ok you don't have to worry about that and the back tends to be the lesser of the two for vibration issues. When you've got the wheel out to change the tyre put the spindle back in and prop it up between two chairs. Give it a spin and see where it stops. Do that a couple of times and you'll soon see how much of a balance prob there is.

Bearing drag will make it less accurate than a pro balancer but that's good in this case as my rule of thumb is once you've identified the heavy spot by spinning the wheel, move it by hand to 90 degrees from the bottom (ie half way up) and release it. If it doesn't move or just moves slowly to the bottom (because of bearing drag) that's good enough. If it moves quickly then you may need to consider balance weights. You can buy stick on ones at tyre depots. If you do the above with the wheel before you take the old tyre off (pencil mark the heavy spot on the rim) and again after you've taken the tyre off you'll get an idea whether any imbalance is in the wheel or the tyre. You can then alter the position of the new tyre to compensate.

With knobbly tyres like TKC80s you need to be a bit more out of balance than with road stuff before you notice it as the knobbles set up their own vibration.

Hi,

i would generell get rid of the expensive tkc wich is not good for tar at all (just melts away, doesn even last 10.000km and sometimes just rips the whole knobs of) and get a Mitas E-07. This tire took me more then 25.000 km all the way from capetown back to germany (without being balanced of course).

Travel save, Tobi

The Mitas will be my next set I think, but I'll stick with the Conti until the front is dead and change them as a pair.

Not balancing while on a trip wouldnt bother me at all, half the time I forget to do it, even when chaning tires at home.