Sunday, September 14, 2008

Wheelbuilding 101, third time's a charm

Tinkering can be dangerous.

I rode the Quickbeam yesterday on one of my regular weekend routes. It was a great day, and I thoroughly enjoyed myself.

While I was riding, I was thinking about my build. My Quickbeam rides so smoothly and the wheels seem to be arrow straight and true. After I had finished my ride, curiosity got the best of me, so I put the QB up on the stand and spun the wheels. Sure enough, nice and round and true. Riv does a fantastic job building wheels!

Just for fun, I put the Ramby up on the stand and performed the same test. The wheels were certainly nice and true laterally, but radially...a bit lumpy. That's a good way to describe it, just not quite round. I never really noticed or checked the roundness of my wheels while I was building, I just figured if everything was trued and tightened up to more or less an equal tension the wheels would be round.

Well, that just wouldn't do. The tires and tubes came off, and back on the stand.

Rear wheel first, and with some good advice from Sheldon and some tinkering I managed to get wheel relatively lump-free and true as well. Of course, the front wheel needed some adjustment as well. As I was tightening and loosening spokes, I noticed a couple of nipples were being a bit stubborn and quite noisy. A nasty screeching, popping, grinding sound. As I rounded off the spoke nipples, I was thinking this wasn't good.

There wasn't any way I was going to save these nipples, or the spokes. Luckily, I ordered extra spokes for my build, so I bit the bullet and got out the sidecut pliers. Snap! Snap! The offending spokes and nipples were history, I rethreaded some new spokes and nipples in place (of course, liberally lubricating the spoke threads), and back on the truing stand.

The same high spot, and the same issue. As I tightened the nipples, they began to grind, pop, and seize up. I didn't even get close to correcting the out of round condition before I once again rounded them off.


Well, I still had a couple of extra spokes. I didn't want to go through the same exercise again and I began thinking about what might be causing my spoke nipples to seize up. The spoke tension didn't seem to be excessive in that area, so I didn't think I was overtensioning. I decided to remove the seized spokes, again, but this time I lubricated the mating surface of the nipple to the wheel rim eyelets, as well as the spoke threads.

Eureka! The spoke nipples tightened without seizing, and I was able to get the wheel resonably round and true.

Lesson learned: tinkering is dangerous, but it can also be educational!


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