jim p

The front rim is slightly misaligned where the aluminum ends of the rim come together. It is only of by a few thousands of an inch but it makes the brakes grab with each wheel rotation when braking.


What are some possible fixes for this? The brake pads are old and probably hard so would some new softer pads pretty much eliminate the problem?

Andrew R Stewart 

First try reversing the rim's rotation direction. Sometimes the throb is less one way then the other. Second it to file down the difference a bit with a flat fine file. This won't fix the rim width differences but will reduce the "catch" at the seam a bit. New pads won't likely fix the problem just as aspirin won't help the broken leg, but they might make you less aware of the problem Andy

Andrew R Stewart 

Dripping faucet? Is that because the rims sold in the wet NW are only to be used/worn down in the rain Andy (who can thankfully say his tours in both the NW and Scotland were largely dry)

I'll add that I mentioned a flat file for a reason. It's to limit the material removal to the high side of the seam best possible. To use flexible sand paper/emery cloth pressured by one's thumb will result in some undercutting of the low side of the joint. The rigid backing of the file helps to keep the pressure mostly on the high points. Andy

jim p

Thanks

I will give a flat stone a try.

Iride01 

I've bought plenty of wheel sets where the rim joint off a little. Usually goes away after the brakes have been used for a hand full of rides. Never had it cause any wear to the brake pads that materially shortened their life.

If the brakes grab so bad that it makes you almost unstable, then yes, sand or file it down some. But if it's just a bump you feel in the brake levers and frame, then it'll be gone soon.

Pop N Wood

You might have a layer of brake pad material on there as well. I would scrub the braking surface clean with alcohol and a scotchbright pad. A red or blue one should work. Scotchbrights are somewhere between sand paper and steel wool for refurbing surfaces.

fietsbob

Next time look for welded & machined brake track rims rather than pinned ones.. ..

Iride01 

I've had just as many welded and machined rims give a bump as I have the pinned rims.

Andrew R Stewart 

I'll add that a pinned seam can be also well machined on the brake track. I have to admit that I see little real in use reason to have a welded seam over a pinned one, assuming both are well done. The seam is under a fair amount of compression and by the time the rim is bent enough to distort a pinned seam the welded rim is generally toast too. Having said that some rims only come in one or the other seam treatment and thus I generally choose the rim for it's width, spoke hole eyes and weight, not it's seam. Andy (who rode home today on s pinned Mavic Open Sports and will ride tomorrow on welded Open Pros, both having spoke hole eyelets. ).

Drew Eckhardt 

A file or wet stone.

Moe Zhoost

Me too. Makes you wonder about the machining process. In any case a few strokes with a flat file takes care of the issue.

jim p

I used a flat stone and a finger nail every board and the joint now seems very smooth. I will test it out this weekend. I decided to lube the bearings and found one cone nut to be pitted. This is an old magic wheel so my next project will be to order some new cone nuts and bearings.

I guess that I will have to measure the axle diameter and the bearings so I can get the correct sizes.

Thanks again for the suggestions.

Iride01 

Pits in the cone are not a problem if they aren't in that very thin and shiny little ring around it. That is the only place the ball bearings touch the cone.

jim p

I could feel the bearings hitting the pits so I just ordered some more cone nuts. I plan on riding the wheel as is until the new parts arrive.

Chuckles1

Softer pads can indeed help to reduce problems with rim irregularities; grabbiness, squealing and what not.

jim p

The sanding worked like a charm. The braking is smooth now.

Thanks for all the help.