Wheel balance?

[Zonacat]

Hi all,

I just replaced a rear wheel, hub, spokes and noticed after I put it on the bike, that when I crank up the speed while it's on the stand, that it seems to have a heavy spot while spinning.

I seem to recall this is normal due to the stem and just plain non-exacting specifications in the tire/tube. But since it's new and I just put it on and spun it, I thought I would ask any of the pros out there if this is normal.

Thanks in advance!

-Brian

[DBD]

Not so much the stem but the seam of the rim is where you tend to get the "hump" and that is usually located directly opposite the stem or should be.

If the hump is very noticeable then the build might be off meaning more spokes on one side pulling the wheel to far towards the rim on the other. Did ya get that? I almost confused my self

How much is it moving?

[mechmann]

if you are indeed talking about the wheel balance, it is fine if they are not balanced. our wheels don't rotate fast enough to necessitate balancing.

the heavy spot in the wheel is due to the seam as mentioned. often the manufacturer puts a tab of material across the seam to help increase strength. the tab of material makes that spot heavy. they place this spot opposite the stem so the weight is offset somewhat, but it never balances.

[Pato]

Ummm.... what do you mean by heavy spot? Do you mean you put the wheel on there without the tire/tube and the same spot always ends up on the bottom? If so that's normal as the side opposite the valve whole will be slightly heavier due to the extra materials from welding/pinning the seam. If you mean you see a hop in the rim then it means you or whoever built the wheel did not get the roundness close enough. If the rim doesn't have a hop in it , but the tire does then either the tire bead is not yet properly seated into the rim or the tire has a defect (if it a large hop and new). Slight deviations in round and/or true measurements in a tire are normal and won't be noticed on mountain tires.

[Zonacat]

Originally Posted by Pato

Ummm.... what do you mean by heavy spot? Do you mean you put the wheel on there without the tire/tube and the same spot always ends up on the bottom? If so that's normal as the side opposite the valve whole will be slightly heavier due to the extra materials from welding/pinning the seam. If you mean you see a hop in the rim then it means you or whoever built the wheel did not get the roundness close enough. If the rim doesn't have a hop in it , but the tire does then either the tire bead is not yet properly seated into the rim or the tire has a defect (if it a large hop and new). Slight deviations in round and/or true measurements in a tire are normal and won't be noticed on mountain tires.

Tire and tube mounted, on the bike, on the stand. Spin the cranks, get the tire moving 10-15 mph, and notice a decent heavyness on one side. Sort of a whompf, whompf, whompf. The seam explaination seems very plausible. I was just surprised as to the amount of the lack of balance. If this were a car, I'd be bouncing down the road.

I will attempt to not worry about it, and chalk it up as normal.

To add, these aren't top quality wheels. I had to replace a bent rim from last week and just bought the same rim that came on the bike 4 years ago. Mavic 317 disc.

Saving up for a dream bike a year or so down the road.

Thanks all!

[Winger]

Take off the reflector.

[Zonacat]

Originally Posted by Winger

Take off the reflector.

Oops, forgot. I also have some cards in my spokes, could that be causing that whining motor sound?