[bpe]

When checking the balance on my front wheel I saw it was out of balance. I thought it was so "lightly" out of balance that 1 weight (1/4 oz) would overdo it and make it too heavy at the weight area. I thought I may even have to cut a weight in half (or even in thirds) to get a proper weight to balance the wheel. Went ahead and tried 1 quarter oz weight and walaa it balanced the wheel. Went ahead and rolled with this and didn't think much of it.

On to the rear wheel​

When balancing the rear wheel I pretty much saw the same scenario. Rear wheel starts off out of balance. Added 1/4 oz weight and now it is balanced. Or is it? Just for fun I added another 1/4 oz to see "how heavy" the weighted area would become. To my surprise it still looked to be balanced. Let's go for 3/4 oz and see if I can overweight it with that. 3/4 oz still looks balanced. Moving on to the full monte, 1 entire oz. Finally it made a heavy spot.

To recap: Wheel balanced at 1/4 oz, 1/2 oz, and 3/4 oz. So what I did was pick the one in the middle and rolled with 1/2 oz. In the past I would have just stopped at the 1/4 oz, figuring anything more would have to be too much.

I wish I would have thought of this doing the front wheel, but not worth back tracking at this point.

In the future I will always be checking to see what the "overweight" is.

 

[ducatiman]

precisely what balance setup equipment are you using, @bpe ?

 

[Ex500D-Can]

I wiggle the axle...a drop of 3/1(thin) oil is not a bad idea either...

 

[fog]

It’s obvious your balancing set up has a degree of inaccuracy equal to 1/2 oz caused by friction somewhere. Any method worthwhile should be able to discriminate whitin a 1/4 oz .

Fog

 

[bpe]

I just use the axle with the wheel semi-installed on the bike. Calipers out of the way, speedometer gear out of the way, rear sprocket out of the way.
There's no real friction. If I spin the wheel(s) fast, equivalent to ~6 or 8 MPH, it seemingly takes forever to come to a stop. When it does come to a stop (before balancing) the wheels will even back up some until the heavy spot is on the bottom.

 

[ducatiman]

"When it does come to a stop (before balancing) the wheels will even back up some until the heavy spot is on the bottom."

"Added 1/4 oz weight and now it is balanced. Or is it? Just for fun I added another 1/4 oz to see "how heavy" the weighted area would become. To my surprise it still looked to be balanced. Let's go for 3/4 oz and see if I can overweight it with that. 3/4 oz still looks balanced."

Can't explain why but somehow the results in the 2 described scenarios seem somewhat contradictory.

My experiences (using a proper balancing "machine") would show blatantly different results with every weight used. I establish the heavy spot, mark it with chalk on the tire, 1st session I move the marked area to 9 o'clock position, let go, it will fall to 6 o'clock....add weight then test for heavy spot again. When balanced, I'll actually fully spin the tire, looking for it stopping in various positions. THEN I know I'm done. Actually, quite a clear pathway.

 

[fog]

The mystery is simply friction. In spite of the OP’s claims the amount of friction was massive compared to the force involved
(1/2 oz).
a proper balancing rid employes 4 tiny ball bearings arranged. To form 2 fee s for the shaft to roll in. This reduces friction to a tiny amount.
Fog

 

[yorkie]

When balancing the rear wheel I pretty much saw the same scenario. Rear wheel starts off out of balance. Added 1/4 oz weight and now it is balanced. Or is it? Just for fun I added another 1/4 oz to see "how heavy" the weighted area would become. To my surprise it still looked to be balanced. Let's go for 3/4 oz and see if I can overweight it with that. 3/4 oz still looks balanced. Moving on to the full monte, 1 entire oz. Finally it made a heavy spot.

this makes sense to me, as you are not using precise balance equipment. you have to guess (more or less) where the heavy spot is. but there could be two heavy spots with the rim and tire combined. these could be say 1ft apart.
on initial test neither spot will drop to 6 o clock but somewhere in the middle as both spots try to be lowest. may be just nearer to one.
add weight to the highest spot and the balance shifts to basically a new heavy spot with the weight it looks balanced but isn't, adding a bit more weight shifts it slightly again but not enough to drastically change where the weight is put. that is until there is more weight than either of the two heavy spots and the weighted part is now the heavy spot.
I hope this makes sense it's as simple as I can make it in a short post. it is a common problem for tire fitters and why most car tires are dynamically balanced to check osillations on a spinnerette and not static balanced.

 

[Apriliarider]

2 words. Marc Parnes. That is all.

 

[bpe]

this makes sense to me, as you are not using precise balance equipment. you have to guess (more or less) where the heavy spot is. but there could be two heavy spots with the rim and tire combined. these could be say 1ft apart.
on initial test neither spot will drop to 6 o clock but somewhere in the middle as both spots try to be lowest. may be just nearer to one.
add weight to the highest spot and the balance shifts to basically a new heavy spot with the weight it looks balanced but isn't, adding a bit more weight shifts it slightly again but not enough to drastically change where the weight is put. that is until there is more weight than either of the two heavy spots and the weighted part is now the heavy spot.
I hope this makes sense it's as simple as I can make it in a short post. it is a common problem for tire fitters and why most car tires are dynamically balanced to check osillations on a spinnerette and not static balanced.

I appreciate the insight and feedback on the subject matter.


For everyone else, it's always good to veer off course a bit when seeing something not being done up to par. So I also appreciate that. I did notice no one has mentioned where this "friction" is originating from. But since the only possible source would be the wheel bearings, I guess I can read between the lines. 😄 I will have to start a thread on wheel balancing in general later. It should be enlightening.

Meanwhile in the interest of time I'm going to have to roll with what I have. Hopefully I will get lucky and disaster won't prevail.

 

[yorkie]

Meanwhile in the interest of time I'm going to have to roll with what I have. Hopefully I will get lucky and disaster won't prevail.

they will be fine you have them within 1/2 oz so pretty much balanced already.
the reason I wrote the above, is experience, the gen 1's rim was pretty much corroded on the bead no matter how much it was cleaned it still would not seal, so I fitted a tube in it. now in doing so I prevented the usual rotate the tyre on the rim move. I had in fact 3 heavy spots around the rim that didn't balance out by themselves. ended up with 4oz of weight (and not all in the same place) every time I found a heavy spot added weight the the heavy spot moved somewhere else, and so on. got it in the end but what a PITA.

 

[bpe]

I'll just keep my speed under 100MPH. most of the time