Bicycle Mechanics - Sheer genius or beginner's luck?

I just recently picked up cycling and am by no means accomplished in the practice of bike mechanics, but today I decided to attempt to give my bike a tune up. Everything was going swimmingly, that is, until I reassembled and remounted my front wheel. For no apparent reason, with every rotation of the wheel the tire would sway about half an inch to either side; or, enough that it alternated between scraping each brake pad without coaxing. After about ten minutes of staring at this scene in a state of puzzled frustration, I said f*** it, took the wheel apart again, and shook out all of the ball bearings. After a quick inventory I discovered that there were only 19 bearings in the wheel. Now, as I said I'm no bike mechanic, but it just seemed like there should be an even number of ball bearings, which either meant that A. My bike was defective from the beginning or B. I'm an idiot and lost a bearing during the tune up process. My tendency was towards B so I scanned my entire workspace, and, after several more minutes of frustration, came to the conclusion that the bearing must have fallen down the drain in the floor. So, in a moment of panic, I quickly disassembled the wheel on an old, $90 Mongoose MTB in my garage, stole a bearing, and jammed it into the wheel on my road bike before I could convince myself not to. Now, all that being said, my front wheel runs better now than it did before, so I ask you: was it sheer genius or incredible beginner's luck?

Are you sure it wasn't the tire not being seated properly? Or the rim being out of true? You'd have to be missing quite a feel balls to have such a deflection at the brake pads. Your wheel probably wouldn't even turn.

A bit of both I would guess. Yes your wheel should have an even number of bearings-ie the same number on both sides of the wheel.

the genious part(for a beginner)- Stealing a bearing from another wheel. That is standard practice for many garage mechanics- but you figured that out on your own-Kudos you have the makings of a future expert mechanic

the beginners luck- not all wheels use the same size bearings- if your wheel is spinning true now you most likely stole a bearing that is of the proper size. If you run into problems with the wheel in the next couple rides I would take all of the bearings out and get new ones from you LBS and replace them all with the correct size. I think you will be fine tho.

also 1 bearing usually will not make an issue-but it could

I assume you were able to properly adjust the cones on the axle when you rebuilt the hub too?

Loose bearings in a hub should pack into the hub cup with about 2mm of space still left so they can spin freely.

It is not possible that the wheel was not properly seated in the dropouts/ends, otehrwise the whole rim would just rub on 1 side, not woble back and forth.

The only way this would happen is if the rim was out of true, but since replacing the bearings solved this without spoke ajustment is was something in the hub. The only other thing I can think of is that the cones were very loose, which would have been corrected with reassembly on the 2nd try.

I would never reuse old bearings. I buy them for about 2 cents a piece. That's 40 cents for your front wheel.

I suggest you read up on adjusting hub cones, and make sure the axle is seated square onto the fork.

+1 Good move borrowing bearings from another bike. Good improvising.

This simple devise measures ball-bearings, spokes, and (with luck you'll never need this) cotter-pins:

http://www.parktool.com/products/detail.asp?cat=16&item=SBC-1

Other companies make these, too. Get the cheaper one if you have a choice. They're all about the same.

I would never reuse old bearings. I buy them for about 2 cents a piece. That's 40 cents for your front wheel.

I suggest you read up on adjusting hub cones, and make sure the axle is seated square onto the fork.

+1 Good move borrowing bearings from another bike. Good improvising.
As long as the bearing are still bright and shiney they are good to reuse. They are harder than either the cups or cones.

Loose bearings in a hub should pack into the hub cup with about 2mm of space still left so they can spin freely.

It is not possible that the wheel was not properly seated in the dropouts/ends, otehrwise the whole rim would just rub on 1 side, not woble back and forth.

The only way this would happen is if the rim was out of true, but since replacing the bearings solved this without spoke ajustment is was something in the hub. The only other thing I can think of is that the cones were very loose, which would have been corrected with reassembly on the 2nd try.


also 1 bearing usually will not make an issue-but it could

I assume you were able to properly adjust the cones on the axle when you rebuilt the hub too?

I think part of the issue the first time was the combination of the bearing cone being too loose and the hub only having 19 bearings. The second time I must've guessed correctly as far as how much to tighten the bearing cone because it straightened the wheel out completely.


This simple devise measures ball-bearings, spokes, and (with luck you'll never need this) cotter-pins:

http://www.parktool.com/products/det...=16&item=SBC-1 (http://www.parktool.com/products/detail.asp?cat=16&item=SBC-1)

Other companies make these, too. Get the cheaper one if you have a choice. They're all about the same.

I wasn't entirely sure of the bearing size, I just sortof eyeballed it and assumed that, since the wheels were of similar size, the bearings probably would be too. Worked out pretty well too.

So you dont have to guess next time on how tight the cone should be:

tighten the cones down go all the way till the axle doesn't move very freely. Now back up the cone just a touch so that the axle does move freely. The object is to get the cones at tight as you can without effecting the purpose of the bearings which is to let the axle spin freely.

If the cones are too tight then the axle doesn't move(and you damage your races and cones)
if the cones are too loose then you will have lateral axle play(and a wobbly ride, unsure braking etc)
it is all about getting it just perfect for the best ride quality and to prolong your hub life

The missing bearing would not cause what you were seeing. I've run into several hubs like what and all spun free and straight.

It is possible that a very loose cone could have 'jammed' in the hole made by the missing bearing, but should have been easily movable and obviously loose when you wiggled the wheel laterally. (Did you?)

Most likely it was just in the dropouts crooked.

I quickly disassembled the wheel on an old, $90 Mongoose MTB in my garage, stole a bearing, and jammed it into the wheel on my road bike before I could convince myself not to.
Panic, sabotage, cannibalism.
I'm glad you got your cones properly adjusted.
But I feel sad for the 'goose.
This is a mean shop.

DMF- wheel not properly seated in the dropouts doesn't explain wobbling of the wheel(unless severely bent axle).

Mis-Seating would cause a continuous rub of one side of the wheel, not wobbling.

It was most likely cones

DMF- wheel not properly seated in the dropouts doesn't explain wobbling of the wheel(unless severely bent axle).

Yeah, you're right. It must be the cone(s).