In support of home wheel balancing

[spalkin]

I started using Dynamic Balance Beads on my last set of new tires. HAppen to be Road Smarts as well. I just hit 4k miles on them, the tires still look new and The tires are still perfectly balanced and no wieghts at all. I still let the deal mount the tires but I instruct them not to balance them, I dump the beads in myself.

I'm using the DynaBeads with my Avon Storms (read; tires that don't have any heavy mark) and they're running smooth. I figure this is because of any of three things:

1) if motorcycle tires are a bit out of balance, you can't tell.

2) the DynaBeads work

3) my tires came out perfectly balanced. (they didn't)

I used my Mark Parnes on the wheels without tires, front: 1/4oz out, rear: 1/2oz out.

With the tires mounted, front: 1/3oz out, rear: 3/4oz out.

I didn't bother trying to re-orient the tires to dial that out.

Put in the recommended 1oz of beads in the front and 2oz in the rear.

I still don't fully know that DynaBeads work. In my engineer's mind, there is no way that those beads can seek out the light spot. If anything, they would seek out the heavy spot and make things worse.

Conclusion: If they don't work, and they're going to the heavy spot, that would mean that my front wheel for example would be 1 1/3oz out while spinning.

Like I said above, smooth as can be.

I guess the question is: how much does a tire/wheel assembly need to be off before you can feel it?

I've never had vibration or out of balance issues with any bike I've owned.

I do know that there's nothing better than positively balancing them and applying weights, and that that should last the life of the tire. Next set I'll go back to weights, balance the hell out of them and see if I can tell any diff.

 

[Crash Cash]

I guess the question is: how much does a tire/wheel assembly need to be off before you can feel it?

Yeah, I have a couple sets of unused Dynabeads. One of these weekends, when I'm really bored, I'm going to slap a couple 1oz weights on a wheel and run up and down Alafaya Trail and see what it feels like, with and without Dynabeads. Myth Busters on bikes!!

(On the other hand, Kari Byron in assless chaps on an FJR is something to think about.... mmmmmm)

 

[spalkin]

That's a great idea. Kari Byron in assless chaps is too.

Or, Kari Byron cooling off some beer :yahoo: .

 

[DaveInMn]

But the tire manufacturers still say to put the balance mark at the stem, for some reason.

A thought:

Maybe this rule-of-thumb is a carry-over from the days (up until ~mid 70's, when cast wheels started appearing) when all wheels were spoked, requiring tubes that had threaded metal stems with those round metal nuts (yah, I know...I'm showing my age) that were screwed on and tightened to lash the valve stems to the outside of the rim?

The spoked wheel assemblies were much lighter than the cast. Even more so, when the weight of the modern braking and drive assemblies are added. When you add the extra weight of the metal valve stem, nut, metal valve cap and the extra rubber to vulcanize the stem to the tube, its easy to see why the heavy area of the relatively light(er) spoked wheel (with the tube in place) was around the valve.

 

[wheatonFJR]

The heavy end of my rims are NOT at the valve stem...so balance the rims and make a mark.

 

[Fred W]

But the tire manufacturers still say to put the balance mark at the stem, for some reason.

A thought:

Maybe this rule-of-thumb is a carry-over from the days (up until ~mid 70's, when cast wheels started appearing) when all wheels were spoked, requiring tubes that had threaded metal stems with those round metal nuts (yah, I know...I'm showing my age) that were screwed on and tightened to lash the valve stems to the outside of the rim?

The spoked wheel assemblies were much lighter than the cast. Even more so, when the weight of the modern braking and drive assemblies are added. When you add the extra weight of the metal valve stem, nut, metal valve cap and the extra rubber to vulcanize the stem to the tube, its easy to see why the heavy area of the relatively light(er) spoked wheel (with the tube in place) was around the valve.

Yeah Dave. That's exactly what I was thinking too. Some habits die hard...

 

[ELP_JC]

I wonder why the wheel manufacturers don't stamp a heavy spot mark on the wheels somewhere.

Take a wild guess. Hint: Answer starts with '$' . But yes, doesn't take more than a minute to put a wheel on a static balancer and mark heavy spot.

And I agree the whole assembly should be balanced as a unit, not the wheel first; if light spot on tire is aligned with heavy spot on wheel, it'd take the minimum amount of weights. Finding how much weight it takes to balance an empty wheel is usually a waste of time IMO, but I had to do it once on the front wheel of my BMW K1200RS, which had an inordinate amount of weight. Turns out the wheel alone needed 42gr to balance, which is pretty much the limit before the wheel is deemed defective. The FJR has small weights on both wheels so will only find the heavy spots. Good day.

JC

 

[bluejag]

Another reason. also cost driven is the combination of Tire sale profit margin less supposed discount to customer for mount and balance equals all the more reason for the lazy tech to do it the easy way. I just had a new storm put on before a weekend trip when I asked why, ( after seeing 63g at valve stem) they did'nt 180the tire? ans: we see them worst than that

My ans: cause you never took the time to do any of those the right way either! I gave up when I asked why they didnt balence & mark the wheel prior to mounting and got the deer in the headlights look and was told that's crazy, why would anyone do that? I rest my case. Being a fleet mechanic I do all my own work excpet tires (I don't have the equipment)

THAT is about to change!!

 

[Fred W]

And I agree the whole assembly should be balanced as a unit, not the wheel first; if light spot on tire is aligned with heavy spot on wheel, it'd take the minimum amount of weights. Finding how much weight it takes to balance an empty wheel is usually a waste of time IMO, ...

Well, it takes only a few minutes and you do it exactly once per wheel then scribble what that value is on the inside of the rim. The wheel is not likely to have changed its balance from tire to tire. The advantage of temporarily slapping on that previously determined weight(s) is that after mounting the new tire you can confirm that the marked spot on the sidewall of the tire is the light spot on the tire like you ***-U-ME it is. Imagine what happens if one decided to mark the heavy spot instead... I've heard it has been done before.

Also, some manufacturers (Avon comes to mind) do not balance mark their tires at all, so you would have to find the light spot yourself and them rotate the tire on the rim (if you want the minimum weight deal. To do that the rim would need to be pre-balanced first.

Or you could just do like all of the stealerships do and slap the tire on the wheel and throw whatever weight on that it takes.

YTMMV

 

[Constant Mesh]

If your bare wheel requires more than 10 grams to balance it might be wise to install one of Yamaha's clip-on center rib weights as a permanent part of the wheel. They offer three different weights -- 10g, 20g, and 30g.

Then you can add minimal additional stick-on weights when you perform the final balance.

 

[Fred W]

If your bare wheel requires more than 10 grams to balance it might be wise to install one of Yamaha's clip-on center rib weights as a permanent part of the wheel. They offer three different weights -- 10g, 20g, and 30g.
Then you can add minimal additional stick-on weights when you perform the final balance.

No, I don't think that you understand the basic idea here. It's OK for the wheel to be "out of balance", you just need to know where that mis-balance is. Most any tire that you buy will also be out of balance by a considerable amount. By knowing where both the wheel and the tire are heavy and light and aligning them 180 degrees opposite you cancel them out as much as possible.

So in my example in post #1, my bare wheel balanced up, out by 21 grams. After I mounted up the tire with it's heavy spot at the wheels light spot that same spot was still light, but now only by 10 grams. So that tells me the tire alone was out by 11 grams. But another tire might only be out by only 7 grams. Or maybe another is out by 21 grams, in which case I would need no weight at all.

 

[Constant Mesh]

I understand but if the wheel's heavy spot is very pronounced as my front wheel is then it may be better to add a center rib weight and make it permanent. For two consecutive front tires (only two I've really studied) the wheel imbalance dominated the tire imbalance and lots of weight (four 1/4 oz. weights -- two per side) was required in the same general location on the wheel. One might add a permanent weight of say 1/2 of the wheel's imbalance and then you would use the stick-on weights to make the final balance.

You end up scraping off a lot of old weights and then putting on about the same quantity of new weights in about the same location.

Maybe if the wheel's heavy spot is very heavy it might be better not to take the old weights off before you attempt a balance. Although if you're trying to equalize the weights on both sides of the wheel you'll probably end up making changes to all the weights anyway.

 

[jekirby]

My rear rim had the light spot at the valve stem also.