Classic & Vintage - wheel out of round?

I have an old centurion and the front wheel is out of round. In other words, the wheel is closer to the frame in one spot as it goes around. Not in the sense that we think of truing but in the other dimmension. Hope that makes sense. I wonder how much of that is acceptable and if there is a fix?

Thanks,

Mirko

On an out of round wheel, check very carefully for stress cracks around the spoke holes in the rim. If you find some, the "fix" is to re-lace the hub to a new rim.

If there are no cracks that you can find, check again..... :D If you still don't see any cracks, you can have the wheel re-tensioned (or do it yourself) and that may solve the problem.

Out of round wheels are the typical symptoms of either spoke hole cracks or uneven tension causing the tighter spokes to pull their respective section of the rim further in.

And for future reference, the condition is called radial runout.

As far as the "how much is too much?"question, Barrnett's Manual says the wheel should be true in both lateral and radial planes to within 0.5 mm. The Park Tool Blue Book says it should be true in both planes to within 1.0 mm.

Personally, when I'm truing and tensioning a wheel I shoot for 0.5 mm, but sometimes settle for less than 1.0 mm.

I believe thats usually caused if the bicycle sat for number of years unused.. probably more likely for a heavier one. If you have the patience you can loosen all the spokes and re-tighten them, worked for me the few times I had that problem - basically rebuilding a wheel without taking it all apart, helps if you have a wheel trueing stand, but I always just used a bicycle fork with lil cut off spokes or whatever lil metal piece I could find taped to it, the poor mans wheel trueing stand (;

I'll give it a go. Loosening and tightening spokes and checking for cracks.

Lastly, if I decide the wheel is shot, what's a good place to buy used 27" alloy wheels? This was a cheap bike and I don't want to put a lot of money into it nor do I want to relace existing hubs.

Mirkee

Sheldon has pairs for $100
http://sheldonbrown.com/harris/wheels/630.html

Not used, but most used stuff I've run across that is used is chromed steel.

I believe thats usually caused if the bicycle sat for number of years unused.. probably more likely for a heavier one. If you have the patience you can loosen all the spokes and re-tighten them, worked for me the few times I had that problem - basically rebuilding a wheel without taking it all apart, helps if you have a wheel trueing stand, but I always just used a bicycle fork with lil cut off spokes or whatever lil metal piece I could find taped to it, the poor mans wheel trueing stand (;
Are you saying that the wheels develop flat spots from sitting unused?

The two types of wheel "roundness:" lateral (side to side), and radial (up and down). It sounds like your wheel is radially out of true. Find the high and low spots in the rim, and tighten the spokes to remove high spots, loosen spokes to remove low spots. Adjust two side-by-side spokes at a time, nearest the high or low spots, adjusting them equal amounts so that the adjustments you make don't affect the lateral trueness of the wheel-

Could be the bike's previous owner was fond of jumping curbs, which will produce nice flat spots. If all else fails, you can get radical: remove a couple of spokes at the flat/low spot, hold the rim straight up and down and support the bottom, put a half round piece of hard wood at the flat spot and give it a few good whacks with a hammer. That probably won't work with steel, but aluminum is quite malleable. It's something to try as a last resort before you trash the wheel.

Neal

those curbs are a killer on rims. If you do it alot and get it just right thay stay round from the even pounding:D

Lastly, if I decide the wheel is shot, what's a good place to buy used 27" alloy wheels? This was a cheap bike and I don't want to put a lot of money into it nor do I want to relace existing hubs.


Go to the "For Trade thread if you have anything to trade.

Pay for a star and post in "Want to Buy" in the Marketplace section.

Or my favorite... Check thrift stores, Craigslist and garage sales for donor bikes to get the wheels and possibly other spare parts... Much like another ongoing thread where one of us is buying a $25 bike for the wheels...

I have done it in the past, it is where I got the alloy wheels to replace the chrome wheels on my Sears bike...

those curbs are a killer on rims. If you do it alot and get it just right thay stay round from the even pounding:D

That must be why mine are all still true :roflmao: .

East Hill