Tire or bent rim

[KSR Moto]

I have been riding my gy6 50 long case scoot for a while now and recently I upgraded it with 44mm bbk, scoot is now very fast and at higer speeds I am noticing that my handlebars are shaking actually more like up and down movement

I own this scoot for a couple of months now and I dont know what happened in the past with it, but the shaking only came up now when the scoot is capable of higher speeds, I am pretty sure that the front wheel is the culprit for this

How do I check if it is the tire or the rim? I dont think that unbalanced wheel could do that much of a shake or could it?

Cheers

[FrankenMech]

Put a block under the front of the frame. Spin the front wheel and check for any wobble either in the bearings, tire, or wheel.

You can use 2-3 Oz of plain BB's inside the tire to balance it if it is tubeless.

[KSR Moto]

Any BB's work or should I get special ones for this?

The only ones I have now are yellow ones for airsoft

[FrankenMech]

Use the steel BBs .177" diameter for BB guns. The steel is copper plated. You can get them at most sporting goods stores.

When the tire is rolling on the ground the BBs will distribute themselves around the inside of the tire. My rear tire was badly out of balance. I used 3 ounces of BBs, -no more balance problems.

Warning, the BB balance method only works when the tire is rolling on the ground. If the tire is just spinning in the air the BBs will gather at one spot and throw the balance off.

Motorcycle and scooter shops also sell 'tire balance beads' for balancing tires but they want a small fortune for them.

[GrumpyUnk]

Can you explain how adding the BBs to the inside of a tire will balance the tire/wheel combination? Please.

I don't get how it could possibly work.

tom

[PirateLabs]

Jun 16, 2018 11:22:30 GMT -5 GrumpyUnk said:

Can you explain how adding the BBs to the inside of a tire will balance the tire/wheel combination? Please.

I don't get how it could possibly work.

tom

I never got that either but, FrankenMech just said something I must have missed.  He said if just spinning the tire off the ground, the BB's will not help balance.  They only work when rolling on the road.  He knows what he is talking about so I know it works but I too can not figure out just how and why they all do not just gather in one spot.

Bill

[FrankenMech]

I have no idea how it works, only that it does. It is a hell of a lot cheaper than taking the tires to a shop for some sort of machine balancing. It is also easy to do yourself. Motorcycle and scoot shops that sell high $$$ balance beads usually charge big $$$ to install them also. Plain old Crossman or Daisy BBs are dirt cheap.

Balance beads and devices have been around for 50 years that I know of. I do know that it does not work with the tire just spinning in the air. I used it on my scoot tires and it has worked like a charm. You can find all sorts of claims pro and con on the net. YMMV


BTW- A rolled up paper tube 'funnel' makes installing the BBs easy. I use a C-clamp to break the tire bead. I am also a Scotsman and notoriously cheap...

[2stroked]

By process of manufacture these tires have thicker and thinner areas in the surfaces. The BBs work by accumulating in the thinner lighter spots as the tire rolls, effectively balancing them.

Now, this is just my understanding of how and why they work, if someone comes along and can tell us that I am wrong, I will stand corrected. However, I do believe that what I've said is the truth.

[jackrides]

I've not yet tried 'balance beads'. Sounds good. Basicly, its all about inertia. The wheel spin has to be fast enough so the beads find a 'sweet spot' and just don't just keep falling to the bottom. Hand spinning is not going to get there.

[FrankenMech]

When you slow down and listen hard the BBs can be heard rolling around in the tire. When you accelerate the engine noise drowns out any sound from the BBs.

Like I said, you can find all kinds of 'discussions' on the web about why they do/can't work with many 'theories' on both sides. I figured it was worth a shot compared to all the effort and expense of taking my rear wheel to a shop for balancing, and then re-balancing later on as the tire wore.

Three ounces of BBs in my rear tire worked for me. The balance beads they sell are supposed to be more dense and since they are expensive they can be re-used. BBs are cheap and disposable. Balance beads of any sort can be removed from the tires if necessary. My rear tire is a 120/70-12. Larger tires may require more beads or they may require less, -there are theories... I did some reading and figured I would try 3 ounces.

[PirateLabs]

FrankenMech: Is there any issue of them causing any wear on the inside of the tire over a long period of time? I would not think so but someone mentioned that to me once and I never really thought about it...or, maybe they said the bbs wear out and need to be replaced after a while...I can't remember now. I just mounted my rear tire a few months ago and aligned the yellow dot and, to my great surprise, it rides as smooth as glass. Going to do my front tire in a few months and I really doubt I will be that lucky again so, the bb idea is way better than paying someone around here to balance it as I think the going rate is like $20 at the motorcycle shop. Plus, I would have to take off from work (a very hard thing to do) because non of the shops are open when I am off.

Bill

[FrankenMech]

I imagine they do kick up little rubber 'marbles' over time. I have seen that happen even in tires that didn't have any balance beads. I have also heard the beads will pick up a rubber coating over time. I suppose the beads would wear the inside of the tire also but scoot tires have a short life anyway. Wear may eventually lead to leaks, -only time will tell. The rubber sealing 'tube' inside tires is only a few mm thick.

I guess one could listen for the BBs rolling inside the tires and if you don't hear them or the tire goes out of balance one could check...

Unless I have problems I will probably keep using the BBs.