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He is vibrating the wheel bearings to overcome the static friction, and allow the heavy side of the wheel to drop to the bottom. When balanced, the wheel will stay in any position, even when static friction is removed. No reason you can't do the same with a shop balancer, which should have much lower static friction in its bearings.
 

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I was trying to figure out what his reference point was if any. I get what he’s saying about extra friction but exactly what are you trying to do with the wiggle in reference to the valve stem?

edit:
Looks like you beat to the punch WintrSol.
 

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I think he was trying to use the valve stem as a reference to where the tire comes to rest, so you can see if the weights change that. A tire marker would be better, IMO.
 

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I agree with WS. But doing it that way has problems. The shaft is smaller than the hole in the bearing, so the bearing might not turn. The inner race of the bearing will try and climb up and over the shaft. That has friction. The balancing tool has less friction than the wheel bearings, and less friction than MR Wiggle system. With the balancing tool, you can spin the wheel at different speed, add weights to test, and generally experiment. I just checked my balancing tool for friction.
Year ago I used a home made tool with very low friction bearings. UK
 

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Is it the best way, I don't know, you could argue it either way. But its similar to what I do except I use the axle itself through the wheel bearings. I didn't realize he was using some kind of rod that was smaller than the axle the wheel will be mounted on.
 

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Discussion Starter #8
All parts of this "balancing machine" is free and everybody (almost) has them. It is very easy to check: if unbalanced tire stops at the same point all the time, it means, it is good.
 

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Any friction in the system will prevent that from happening. I described what I believe is a friction problem with what the OP posted. UK
 

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Even if the wiggling overcomes static friction of the bearing races against the 'axle', there is still the problem in irregularities in the surface of the 'axle', which won't be overcome. The actual wheel bearings won't be turning, since his 'axle' is so much smaller than the actual axle. Also, he seems to be of the opinion that shop balancers rely on the wheel bearings; while some may, better quality ones have their own low-friction bearings.
 

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Again I agree with WS.
You do not rely on the bikes wheel bearings. They have too much drag. On the subject of drag. Some folks dismiss it as being minor. Whereas drag or friction is everything. IMO. To illustrate: recently there has been build 75 foot sail boats that lift out of the water on foils, which have less drag than a hull sitting in the water. Going towards the wind, a conventional fast 75 foot sail boat would do about 10 knots. The foiling boats are doing 25 to 30 in 8 knots of breeze.

Back to the point made by WS and why I checked my balancing tool. The BT has its own bearings on a shaft. It is these two bearings that are turning, and they have less friction or drag than the bikes wheel bearings. I have not checked yet to determine if they will accept a very light weight oil. The device I used many years ago would.

Speaking of balance. Henry Royce said we only need to balance an engine, to outside its operating range. So if the engine ran to 5500, and we balanced it to 5750 or 6000, then no problem. We do not need to balance it to 10000.
Here I will make an assumption. If we balance a wheel and tire to run smooth at 150 mph, I think it will run smooth at 200 mph. The logic may not follow the first example, but we have mass going in one direction. An engine has mass changing direction.

On Yami I had the shop put in beads in the front tire. The wheel would chatter up and down at 125 kph. I had the beads removed and they balanced it with weights. Same result. When I put on new tires last year I balanced them. No more problem. UK
 

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I'm not sure that we need to eliminate bearing friction. When the wheel is mounted, it will rotate with the built in bearing friction which will be on a number of points at the same time. With a smaller rod in the center only resting on the top of the axle shaft hole, not only will all weight be on the top side bearings, but the center of the rotation will be off center to the top side. You don't want that. You want the center to be in the center of the wheel.

Plus see post #6.
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One time we balanced a single wheel / tire assembly three different times on three different electronic spin balancers. The weight location placement needed (according to the spinners) came out different all three times. Then we balanced the same wheel on three different bubble balancers. All three agreed, same weight placement every time. I've tested my shop bubble balancer up to an indicated 170 MPH. No shake, no problem, every speed up to 170. It works.

Starting out in the early days of my poor country boy, make it work roadracing, I balanced wheels the static way using the axle thru the bearings. Yes there is drag to deal with but there is a way to make it work.
When you slowly spin it l left note exactly where it stops. When you slowly spin it l right note exactly where it stops. When it stops exactly the same distance, from bottom, left spin or right spin you've found the heavy spot. Add some weight at top and keep repeating until it stops at a different position every time. As you slowly spin take note of how slowly (or not) it stops moving. When it stops the same way / speed every time, both directions and with wheel in different positions you're ready to race. Takes time and patience but it will work. This method was only tested up to aprox 155 ~ 160 MPH. (We never ran speedos on the race bikes).
BTW, I stopped watching the video when I noticed a small "rod" thru the bearing...

S F
 

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If we balance a wheel and tire to run smooth at 150 mph, I think it will run smooth at 200 mph.
I don't think so. Do you remember the balance machines that would spin a tire/wheel while mounted on a car? I had one where the normal speed at the time of 55mph a balance was just fine. But when I got a lead foot and open road it would shake the heck of me at 120mph. So in the previous example of balancing high for a motor, does it too have a spot lower where things are not well balanced or is the above example I have just specific to that style of balance machine?
 

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Actually I solve the problem by using Ride_On tire sealant/balancer. It moves around inside the tire to balance even after the tire is worn more in one spot than another, in addition to protection against most punctures. At least it's supposed to. So I don't use any weights at all.
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Actually I solve the problem by using Ride_On tire sealant/balancer. It moves around inside the tire to balance even after the tire is worn more in one spot than another, in addition to protection against most punctures. At least it's supposed to. So I don't use any weights at all.
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That's been my way as well. Unfortunately the only test of sealant was a bolt that poked a ¼ inch size hole in the tire. They state upfront that's too big a hole to seal. The stuff did slow the the leak enough that I didn't get a tank slapper before it was flat so I say it saved my butt even if it didn't seal a too big of hole. And I love not having big ugly weights hanging all over the place.
 

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I don't think so. Do you remember the balance machines that would spin a tire/wheel while mounted on a car? I had one where the normal speed at the time of 55mph a balance was just fine. But when I got a lead foot and open road it would shake the heck of me at 120mph. So in the previous example of balancing high for a motor, does it too have a spot lower where things are not well balanced or is the above example I have just specific to that style of balance machine?
Both of your points are good, and I agree somewhat.
The case for the engine, is valid IMO, but we may need an engine builder engineer to help us with it. I decided to quote Henry Royce, who wrote that about 100 years ago when engines ran much slower. His engines were very smooth, and had some pretty advanced pieces in them.

The tire spinning, causing a larger gravitational pull as it increases in speed. Trying to send the outer bits in to orbit.
The balance problem has to get worsa as the speed increases. I suggested that if it had not happened by 150, could we assume it was okay at 200. Further, if we balanced the wheel correctly, we should not have any problems. A slightly out of balance wheel would show itself at some point. I think we need to chat with a Ducati MotoGP mechanic, and ask him or her, how they balance their wheels. I am positive it will not be using a shaft, smaller than the hole in the bearings. Another issue with higher speeds is the tire losing shape, or coming apart. Barry Sheen at Daytona, had the tire expand and rub on the frame, and blow at around 180.

For most of these things, we have to be like Einstein and do thought experiments.
For the engine: Mass changing direction, and piston speed are the main issues. The main problem with long stroke engines. I have BTDT.
I have run many times, maybe thousands of times at 145, and would have gone faster with more giddyup. But I have not run 200. The MotoGP bikes do it every lap on most tracks. UK
 
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