lacing rims

W

woogie_man

New Member
Hey guys,

Well I have a 29" tire from a mountain bike that I am wanting to put a coaster brake in. I have a 26" wheel that the coaster break is currently in. Hoping to try and swap the hubs so I can use the manic mechanic hub adapter.

Any thoughts or hints on how to go about my first adventure?
 
You will need to properly calculate the correct spoke length that you will need, and you will have to order the spokes. Search online spoke length calculator, then you will need to measure the hub and rim you plan to use, input the measurements into the online calculator, and it will tell you the correct spoke length. You can also find online tutorials for lacing and truing rims. Its not terribly difficult, it may take some practice but once you get the hang of it you will love it. There is an amazing sense of accomplishment that can be had from building your own wheels.
 
I was wondering about the spoke lengths. Really hoping that the hub I am planning on using is the same size as the hub in the wheel already. Then I am thinking it will be a straight swap for the hubs, and the spokes will remain the same....at least I am hoping.
 
Also make sure the number of spokes for the hub is the same for the rim. Usually 36 spokes. If the hub size is close to the same you should be able to reuse them. You can also change the lacing pattern from say a three cross to a four cross to "change" the length.
SB
 
With the rear wheel you may have to dish the rim also. The front wheel the rim can be center of the hub but the rear the rim will have to be off center of the hub.
 
Rear wheel is never centered.
It's always off due to the drive gears
The wheel is "centered" to the outer cones to compensate for the gears.
 
I can see a cassette wheel needing dished, but I've built a few wheels with coaster hubs for pedal bikes and friends motorbikes. Currently working on my own first motorized bike, and I built a rear wheel with a moped hub. I've never dished a single speed rear wheel, and I've never had any problems nor have my friends with the wheels I built for them.
 
Yeah, single sprocket rear wheels aren't gonna really "need" dishing. I've built quite a few 27-inch and 700c wheels with 5-speed and 6-speed freewheels. These were all going in 1970's Schwinn 10-speed frames with very little clearance between the chain stays. So proper dishing was mostly necessary.

Funny thing, it seems that most of the old Schwinn wheels from the factory had the same length spokes on both sides of the rear wheel. You can get quite a bit of dish by tightening/loosening the spokes just a millimeter or so. (And therefore easy to have the dish far out without noticing). But since the purpose of my rebuilding the wheels was to put in quality stainless spokes, I always used drive-side spokes that were 1 or 2 mm shorter.

Anyway, even though a single sprocket wheel doesn't need much dish, it's a good practice to measure and know the dish when wheelbuilding.
 
I've never thought about dishing a single speed wheel. Since the wheels I'm building are brand new, I didn't have anything to measure for comparison. The front is a Yamaha dirt bike drum, and the rear is a 90mm moped drum, both laced to 24" bicycle rims with 11g spokes.
 
The wheels I've done tend to be for heavy bikes, cruisers, with fat tires. Spokes are the same length and I build them centered. The only geared wheels I've done are internally geared as with Sturmey Archers. They, too, are built centered and trued the same.
SB
 
Well I looked at the wheels and realized it was going to work. The axle length on the larger tie is longer than the one on the coaster wheel. So I talked to a buddy at work and he was able to make me an adapter for my manic adapter. Everything is bolted up and looks like it is going to work. Just need a little longer bolts for my mount, and I should be riding!
 
No offense, but unless you have a lot of experience building wheels and a really good eye for it, there is a lot more to wheel building than looking it over and comparing axle sizes. There are at least 4 or 5 measurements that usually need to be taken to determine spoke length. And different axle lengths would actually indicate one hub is wider than the other, which affects spoke length. Also, cassette hubs are normally dished to allow chain clearance on the pedal side, while a coaster brake will be centered. Thus will also affect spoke length.
 
Also, cassette hubs are normally dished to allow chain clearance on the pedal side
Click to expand...

Actually, dishing won't affect chain clearance. The axle locknut will sit in the dropout in the same place regardless of the dish. Dishing moves the tire to the right, towards the chain, giving less clearance. But the purpose is to have the tire/rim centered between the locknuts, hence, centered in the frame stays.

dtv5403 is right about the importance of spoke length. You only have about a millimeter or two to play with. If you're buying spokes, a mistake will be expensive. But even if the spokes are free, building a wheel to find out the spoke lengths are wrong is a pain (but should tell you what lengths you really need).
 
Lacing wheels is easy. I do it in this order:

Lace inside spokes first, both sides. They should all be pointing in the same tangential direction from the hub. ie, "left"

Lace outside spokes in the other direction, each one "over, over, then under" the inside spoke it crosses.

Tighten all spokes to where the bottom of the nipple flat just meets the spoke end. Best done with an electric screwdriver or drill.

True your wheel up-and down first, then side to side, then check your up-down again.

True it to center. Dishing single speeds is for moving sprockets over due to super fat tires, which you would accomplish by simultaneously moving left axle nuts and dishing the wheel over to the right.

Quick tip: when replacing a damaged rim, zip tie all the spoke crossings nearest to the rim, remove all nipples and switch rims. Easy.

Building wheels will bring you great satisfaction. I once built a klunker type bike on a steel diamond MTB frame, 26" road tires, cut a CB hub from some cheap kids bike and slapped together a fast little shop bike. Thinkin' about it and the road tires I had on it kinda makes me want to build another one.
 
The video culver posted should be all you need. Don't worry about building dishes into things,it'll just confuse a fairly easy job (lacing). Worry more about truing and getting that right. I see a lot of people here with dozens of ideas on that too. Drop it at a competent bike shop after lacing if you don't trust your own work. Shouldn't be much for truing
 
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