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Tire Spin Balancing

G

GREGFUESS

Guest
If this is in the wrong area of the forum, please accept my apologies and feel free to move to a more appropriate area.

Is spin balancing motorcycle tires something that you consider significant to the performance of your tires?

I was in the local shop (not a BMW dealer) having some new RP3 tires mounted front and back of my R-bike (the model is not significant to this thread). In talking to the mechanic, he stated that shop policy is not to spin balance the tires. The claim was that they have never noticed that they get wobble, uneven wear or other objectionable behavior from their tires, despite the not spin balancing.

My thought was that this shop's primary business is to buy and resell used motorcycles, and that they do not receive feedback on the tires that they mount. But these guys are close to the house, and have mounted several sets of tires for me, and I have not noticed objectionable behavior, either. I hadn't been aware previously that this was the shop practice. They have been leaving the weights on the rims, causing me to think that they were balancing the tires. Oops.

I have always run Avon Ultra Storms, and generally get 8~9k miles per set, without noticing unusual wear characteristics. I am hoping to get better endurance from the RP3's. Am I risking tire longevity because the tires are not "balanced"? Am I open to other types of problems?
 
I consider balancing important. But, I must admit, I've not played with it. Next time I mount tires, I will note the weight and where it needs to go, then ride the bike w/o the weight and with the weight to see if I can spot a difference. Since most of my bikes need 14g or less, it might not be noticeable.

One thing I'll toss out is that spin balancing is faster, but not necessarily better, than the static balancing done with a No-mar or Mark Parnes, etc. type balancer. Ever notice the guys racing at AMA races with millions of dollars of equipment in the huge sponsored motorhome type trailer shops? They don't use spin balancing, they use the rod balancers. That has to tell you something.
 
Always Spin Balance

Back in the 70's we changed our airhead tires in the garage and never thought of balancing. We are a lot smarter now...

Have a tire changer in the garage. Change 3 sets a year on my K12RS. Change another dozen sets a year for other riders. Tube and tubeless tires. Every newly mounted tire gets static balanced using a No-mar balancer. Balanced is better. YMMV
 
We are a lot smarter now... Balanced is better. YMMV

I am asking out of ignorance and concern, why is balanced better? Can you feel the difference, or notice a smoother ride? I haven't noticed the difference, so am (wrongly?) concluding that the difference is in the durability of the tire.

Does this match your experience?
 
My response to the exact same question in another forum...

- - - -
Why balance a motorcycle tire?

You can put a tire on a bike, never touch it or balance it and it will run forever... there's no reason to balance that tire, right??? WRONG!

Look folks... you put a new tire on a bike... balance the damn thing or put beads in it. To not balance a tire is idiotic. Sure, you may not feel anything in your ride. You may tool happily down the road without a care in the world thinking that balance of a tire is just dumb.

Let's look at the mechanics of an unbalanced tire. And not from the standpoint of the tire.

The tire uses an axle or drive wheel to attach the tire to the bike. These axles and drive wheels (not to mention the hard mounting points) have bearings and sleeves and other parts that keep the tire doing its job. While you may not feel a vibration as you drive, the mechanics of the bike damn sure does. Failure of the bearings and or axle or any other number of parts and pieces can be a problem. If not failure, at least a massive amount of wear can occur in those components.

That tire that's mounted to the bike is also attached to shocks (of one type or another). The primary purpose of the shock is to dampen the perceived amount of bumps and vibrations that naturally occur in our pristine roads (I can show you a pot hole that has a visitors center). Again, that shock will do it's job only to keep you from noticing the wear and tear on other parts of the bike that make the wheels go round and round.

I would talk about brakes, steering dampers, pivot points, wiring, chains, drive axles, tubing and a whole slew of other stuff, but I hope you get my drift.

Repetitive vibration kills mechanical components quickly (Isn't that the 63rd article in The Constitution?). Balance in a motorcycle tire is crucial to keeping the mechanical parts (that which keeps you on the road) in good condition.

- - - - -

Just balance it... Better to be SAFE then SORRY!
 
I am asking out of ignorance and concern, why is balanced better? Can you feel the difference, or notice a smoother ride? I haven't noticed the difference, so am (wrongly?) concluding that the difference is in the durability of the tire.

Some tire/wheel combos are better balance than others. Also, tires are better made these days, at least with respect to balance. Some tire manufacturers don't even bother marking the light spot on the tire any more. I balance my tires (static, not spin) but found that MOST of the time I was putting the new weights the same place I took off the old weights and using the same amount of weight. Turns out that my tires were pretty much balanced but my wheel wasn't.

If you get an out of balance tire/wheel the danger is that at certain RPMs with the right road condition the out of balance will synchronise with suspension movement, entering a positive feedback cycle that can wind up with the wheel literally hopping down the road. Throw in some older shocks with little damping and it can get interesting.

Short version, I check the balance, but rarely have to do anything about it since I balanced my wheel with tire off and don't remove those weights.
 
For the past 1.6 million bike miles on our several BMWs I have used a static balancing stand and have never seen any deleterious effects from the lack of dynamic spin balancing.

Here is why. Spin balancers balance on both axis - radial and axial. Getting a good axial balance (inside and outside) is important on car tires, and the wider the tire the more important it is. That is why you will see them put weights on the inside and outside of a car tire at different locations around the circumference of the wheel.

Our tires are narrow. Even if spun on a dynamic balancer, weights normally go on the wheel at or near the center, or on both sides together, and axial balance is ignored.

Now if I had a big fat tire on the back of my cruiser drag bike it might make a difference but with the narrow tires normally mounted on my motorcycles a precise static balance on a balance stand is just fine.
 
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Be wary of having your tires balanced at shops that do a lot of tires (especially wide/heavy Harley tires).

Motorcycle dynamic tire balancers have the axle supported only on one end quite a distance from where the wheel mounts.

Shops almost always put the "new guy" busting tires.

When the "new guy" drops a heavy wide wheel on that axle a few times, he can slightly bend the axle of the machine thereby rendering the machine inaccurate.

Next time you have someone dynamically balance a tire for you, try to look at the tip of the axle as it spins. I have seen at least four DIFFERENT machines at six or so different places have some degree of runout. That's why I bought my own mounter and STATIC balancer.

Static balancing is just fine for 99%of the tires. An added plus is it is very easy to check the rim for ANY runout (axial or radial) BEFORE you mount the new tire on it.




:dance:dance:dance
 
Now if I had a big fat tire on the back of my cruiser drag bike it might make a difference but with the narrow tires normally mounted on my motorcycles a precise static balance on a balance stand is just fine.

Paul, I appreciate and respect your opinion and so want to clarify that they did not balance the tire at all, neither dynamically or statically. Do you agree that even if nothing is felt in the control of the motorcycle or noticed in tread wear patterns, that the higher frequency vibrations could damage the mechanics of the motorcycle?

If so, I will take the bike elsewhere to have some kind of balance performed. Certainly will not take tires to this outfit for mounting again.

Appreciate your recommendation.
 
Paul, I appreciate and respect your opinion and so want to clarify that they did not balance the tire at all, neither dynamically or statically. Do you agree that even if nothing is felt in the control of the motorcycle or noticed in tread wear patterns, that the higher frequency vibrations could damage the mechanics of the motorcycle?

If so, I will take the bike elsewhere to have some kind of balance performed. Certainly will not take tires to this outfit for mounting again.

Appreciate your recommendation.

There have been times that circumstances dictated that I didn't balance a tire. Maybe I didn't yet have a wheel adapter. Or I changed the tire in a campground while on the road. In those cases, if I didn't feel any vibration or thump at elevated speed where I might be passing, for example, I simply didn't worry about it.

While I can't establish this scientifically my attitude is that if I can't feel it I don't worry about it. And I get way better than normal life out of wheel bearings and have never had a final drive issue.

That said, and those are the exceptions, it is good shop practice to balance every tire and I do so except in those odd circumstances where it isn't practical.
 
There have been times that circumstances dictated that I didn't balance a tire. Maybe I didn't yet have a wheel adapter. Or I changed the tire in a campground while on the road. In those cases, if I didn't feel any vibration or thump at elevated speed where I might be passing, for example, I simply didn't worry about it.

While I can't establish this scientifically my attitude is that if I can't feel it I don't worry about it. And I get way better than normal life out of wheel bearings and have never had a final drive issue.

That said, and those are the exceptions, it is good shop practice to balance every tire and I do so except in those odd circumstances where it isn't practical.

Thanks. I am not sure what I will do, but I will definitely not return to that shop for tire mounting. Your experience and thoughts are appreciated.
 
Two weeks ago I mounted and static balanced two new tires on my 2005 GS. I put on Shinko radials, and removed old Anakee's. (all by myself for the first time)

The ride is smoother at speed. The vibration in the handlebars is gone and I though that the vibrations were from the engine and now see that the tires must have been out of balance.

I can see where balancing is good, whether you can feel the difference or not.

If you can't mount the tires yourself, you surly can balance them yourself after taking the home knowing that it is done right.
 
My dual sports, I don't balance. My street bikes I static balance. My understanding is that most race teams static balance tires, if it works for them....

As for a shop not balancing a street tire; find a new shop.
 
I have always static balanced my tires, because I can and it gives me a better feeling of confidence on the rare times I tap triple digits. I have been using Shinko 009's and had several of them needing little or no weight after pre-balancing the rim, marking the heavy spot on the inside with "magic marker", then aligning the "light spot" on the tire with it. Shinko marks are hard to see--a little red sunburst about dime size, and it goes away with the first rainy ride or bike wash---soooo, I now mark their mark with a little tire pen in case I have to pull a 1/2 worn tire off to mount a new one for a longer trip, then re-mount.
Also, I never get a nail in an old tire--it's always a new one .:)
 
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