[THEMANRACING]

There is a slightly different way. They have a machine that has an arm that rolls along the outside of the tire while it is spinning. It takes into account the roundness of the tire and also partially loads the tire which is more realistic.

These machines are not yet made/used for motorcycles. But they are the best way to get your car tires done.

Shops use the spin balancers because they take far less talent and far less time. Typical motorcycle spin balancer is 3 G's.

Motorcycles tires that are from a major brand name are going to be very well balanced when new. It is not uncommon for the unbalance to be in the wheel assembly.

 

[THEMANRACING]

To answer the original question, 40+ years of sometimes me & my static balancer & sometimes the shop & their dynamic balancer, no difference detected. Nary a shake, wiggle or vibration.

I think for motorcycle tires dynamic balancing isn't needed as it can be for cars. When's the last time anyone ever had weights distributed to different sides of their rims due to a lateral imbalance? Mine always get clipped in the middle.

I also think themanracing is correct in the good balance of modern quality motorcycle tires. In recent years mc tires no longer have a mark for the heavy side of the tire that use to placed away from the valve stem. Also, a few times lately new tires haven't required any new/different weights to balance them.

A lot of tires still have a yellow dot on the sidewall. That dot represents the lightest part of the tire, and should be put inline with the valve stem (not across from it). It allows you to use less weight to balance a tire. That is good for the shop doing it, and good for the bike.

 

[THEMANRACING]

When I had my balancer it had the ability to match a wheels heavy spot with a tires light spot. It takes a lot of time to do though.

 

[THEMANRACING]

I don't think it is luck. Quality motorcycle tires designed for our bikes are by nature going to be really good.

Cheaper tires, and maybe lower rated speed tires could be less quality....

But when michelin set out to make a tire that fits both our Ninja, and a Hayabusa and a Zx14 you can be sure it is going to have very tight tolerances for roundness and balance. We are reaping the benefit of our tires fitting much faster bikes to be honest...lol

 

[THEMANRACING]

I meant to post this the other day, but forgot.

I believe it is an incorrect assumption to assume that uneven tire wear near the end of a tires life is caused by balance.

Was it still balanced when it was near the end?

The road surface is not consistent nor are braking and acceleration forces applies to the tire, nor suspension loads applied to the tire. I think there are way too many variables in a street tires life to narrow uneven wear to any one thing.

I would be extremely surprised if there was much of a difference in rubber thickness around the tire with the quality tire brands.

 

[THEMANRACING]

Has anyone else experienced it on a motorcycle where you let go of the bars and as the bike slows down it starts to get head shake, gradually worse and worse until you have to grab the bars? Tends to happen at the same speed over and over....

This happens because the front tire is out of round. Now it did not do this when the tire was new, because when new the tire was round. Tires do not wear evenly.

Now you can balance the front tire/wheel assembly when you have this happen, and you will notice it will keep on happening. The only fix is to replace the front tire.

Tires don't wear evenly because what they touch is not even and the forces applied to them are not even. That is my opinion anyway

 

[THEMANRACING]

Absolutely. In my experience it's right around 40-45 mph and multiples thereof. And it sometimes has NOTHING to do with the tires. I've experienced this when:

Put a top case on a '90 VFR. Anything over a pound or two in it and got that symptom.

Ventura luggage on multiple VFRs did this IF the case was mounted behind the rear seat. Flip it around so the bag was over the passenger seat and all was stable.

An ST1100 with what turned out to be a bent rear shock rod (new from factory) had this same problem.

Dunlop tires in the early 90's on my VFR did this after a couple thousand miles. They cupped and vibrated and caused the headshake as well. Running them at lower pressure solved the problem but I didn't like the handling.

A Metzler bias ply tire on my '87 VFR did this from new. Took it back and got it rebalanced. Same issue. Finally someone noticed the runout on the tire was out of spec. A new tire fixed the issue. Runout, in this case, was left-right motion of the tire when you spun it on the balancer. It was about 3mm and the maximum spec for it was about half that I think.

Flattened steering head bearings did the same thing. Replacing them fixed it.

There were articles back in the day about loading motorcycles and how any weight behind the rear axle was bad news. This kind of headshake was pointed to as one of the symptoms of an improperly loaded bike. It also had a lot to do with fork flex, tire sidewall flex, frame stiffness, etc. so things might be a bit different now with upsidedown forks, stiffer frames, bigger tires.

The thing that always fascinated me was that one finger on the bars and you never knew the headshake was there. Given total freedom, it shook like crazy.

Hands off the bars on the Ninja causes nary a wiggle. See:

View attachment 80291

Boss we will just have to agree to disagree on this one. I have had a very different experience in my motorcycle life. Having worked at a couple of different motorcycle shops and in doing so having the chance to ride a ton of different motorcycles on test rides and what not, it has always been my experience this happens with a worn front tire and is always fixed with a new tire.

Your Metzler tire experience is another example, although new, it was the runout (out of round) that caused the headshake with hands off.

I have personally experienced slack in a rear suspension linkage causing head shake, but not shaking when you take your hands off the bars.

Typical head shake as most people know it happens when you are leaned over and on the throttle. The tire hits a bump and in doing so becomes out of round, the forces acting on the tire fight to get it back round be keep over shooting causing the wobble that is no fun. Certainly many things can make it happen more frequently or make it more violent, but typically starts out with a bump on the throttle.

I know I would get wicked head shake landing fast wheelies with a low psi tire on my R1.

 

[THEMANRACING]

And next pic we need a one handed wheelie Can be a sit down to start with if you like, but then working into a stand up one hander

 

[THEMANRACING]

I've had this on most of my bikes at around 40mph. My Ninja does it right now. Haven't been able to pin down the cause though I haven't tried very hard yet.

Reminds me of that joke:

Rider: Hey Doc, it hurts when I go like this.

Doc: Well don't go like that.

You should first re-balance it for sure. It will be informative. After that I bet you $130 that a new front tire makes it go away...lol It's pretty common.

 

[THEMANRACING]

I'll hand that one off to bakwheeltango! Can't wait to see that video either.

As I've noted my experience is pretty much limited to VFRs but I only report on my experience. I find this a fascinating issue because no matter how much I've read over the years I still don't quite understand it. Especially the rear loading and bent shock rod causes of head shake.

Personally, I feel headshake is an indication of something out of whack so I try to track down what's causing it because I don't want a "hands off" shake at 40 mph to bite me in the a$$ at 120.

And Hey sqid, riding a motorcycle can hurt you so don't do it!

I think this is where you are me are having a difference of opinion.

What causes a hands off wobble at 60-40 mph has nothing to do with what causes an actual head shake while under power. They are two completely different things.

 

[THEMANRACING]

About six months ago on my DL650, I mounted a new Michelin tire Pilot Road 3 - the first time I put on a pure street tire. From day one, it had an annoying wobble on hard deceleration and certain speeds above 85MPH. So mostly I didn't notice it but I knew it was there. I mount and painstakingly statically balance my own tires. At one point I reseated the tire and rebalanced it but it still had the same problem. I then took it to someone with a Snap-on spin balancer and it calculated the same amount of weight with 1/2" of where I had it placed. That too made no difference. I then statically checked the wheel for runnout and it was fine but the tire had a slight lateral deflection of 2-3mm. I had been an ardent Michelin tire fan and didn't want to believe they sold me a defective tire and it was the last thing I checked. When I contacted Michelin they suggested I take it to an authorized dealer. I didn't do that because I bought the tire online and even if a local dealer agreed and offered some kind of credit it would have been towards an inflated tire with installation costs. I called the online dealer where I bought it but because a few months had passed they were less than sympathetic (I would not have been either). I have since sold the bike but I learned a lesson that you have limited recourse when you buy a tire online and not all new tires are perfect - even from major brands.

I have seen several people complain about the braking stability of the PR3's. I had them on my VFR and loved them, but I have seen several people with negative comments. No doubt caused by the odd tread pattern.

I would have Michelin replace it, and see if it is the tire. It may just not work well on your bike, but without trying it out you will never know.

Like Rc suggests call them, and don't take no for an answer. Make sure they understand it is a NEW tire, and you expected better.

They are never going to help you with a 4,000 mile old tire...lol