Tuesday, February 3, 2009

How to Build a Bicycle Wheel

Building a bicycle wheel sounds more complicated than it is. While it's true that a high performance bicycle wheel is a work of art created by a master wheel builder, constructing a basic bicycle wheel is fairly straightforward. The skill isn’t in arranging the spokes but rather in making the wheel perfectly true with no wobble side to side or bounce up and down. Most bicycle wheels have 32 or 36 spokes and are laced in what is called a cross-2 pattern. There are several other exotic lacing patterns, such as radical lacing that go straight from the hub to the rim, but these are advanced wheels for specialized applications that the DIYer probably wont tackle until they become wheel building experts.

With a standard 32 spoke wheel with a cross 2 lacing pattern there are 4 different spoke orientations: the inside and the outside of the left hub flange and the inside and the outside of the right hub flange. Therefore, there are eight spokes in each orientation and they take turns going around the rim. This means that out of four spokes, 1 and 3 are going to one side of the hub (each exiting the hub flange on opposite sides) and 2 and 4 are going to the other side of the hub (exiting the opposite hub flange on opposite sides).

With a little practice, you can build your own cross-2 pattern wheel. Your first wheel should probably be a beater because it will take a little practice. I’ve done a bunch of wheels and still haven’t been able to make any that come out flawless. So leave the high performance wheels to the professionals, but don’t be scared to make wheels for a beater bike, replace broken spokes or true a bent rim.

My neighborhood cruiser bike suffered a seriously bent rim when it was chained up on the street. This bike has been on the street for nearly two years and this is the first time anyone has messed with it. The rim was way too banged up to repair, so I decided to replace it. Fortunately there is an ample supply of discarded bike parts in the trash here in New York City. I found a wheel in the trash a few weeks ago. It has the same number of spokes as my cruiser wheel so is a good candidate to lace up to my cruiser hub. Plus, because I am putting a new rim on a wheel that is already laced, I can simply move the spokes over one by one, keeping the pattern intact.
I started by removing the spokes from the new rim. I unscrewed the nipples with a spoke wrench and finished them off with a screwdriver from the other end of the nipple. Save these spokes- you never know when they might come in handy!
Next remove a nipple from the bent rim and move it over to the new rim. Work your way around the rim, removing nipples from the old rim and moving the spoke to the new rim, keeping the pattern intact. Don’t tighten the nipples too much at this point, just connect them. To keep the wheel as true as possible, you tighten the nipples evenly all at once. Once you get about half way around the rim, you can push the spokes out through the rim and remove them without the rim being in the way.

Once you’ve moved all the spokes over to the new rim, begin tightening them uniformly around the entire rim until the spokes are tight. This uniform pressure around the entire wheel is what makes the wheel true. When the spokes are tight, mount the wheel and give it a spin to see how wobbly it is. When you identify a wobble, tighten the spoke that pulls the rim to the opposite side of the hub (or loosen spokes going to the same side of the hub as the wobble. Eventually you’ll eliminate the wobble and you’ll have a reasonably true wheel. As I mentioned above, it’s really tough to make a flawless wheel, but for a basic wheel, this is certainly a project you can tackle yourself!

2 comments:

Chance said...

Just stumbled over your blog and so this comment is fan mail more than anything. I just spent an hour reading your posts -- thank you so much for taking the time and effort to instruct, I really appreciate it. I'm using your dandelion wine recipe in the spring in Vermont - how did it turn out taste-wise?

madeinmanhattan said...

Thanks for the comment Chance. I havent opened a bottle of the dandelion wine yet. Was going to save it for spring. I'll be sure to post a review when I crack open a bottle!