So I'm building up this single speed freewheel bike on my old, Sears Ted Williams frame.

I'm waiting for the single speed freewheel to arrive from an ebay seller. I've laced the rear wheel and got it round but haven't centered the rim or trued it up yet.

I need to add a couple of spacers under the lock nuts to bring them out to 120 (since its a BMX hub). Looking at the wheel in the frame, it looks like it would be best to add them only to the nondrive side to get the single freewheel out as far as possible for good chainline; in effect a reverse dish!

Or should I just put one spacer on each side and center the rim?

Wheel will only be used on this bike, so oddness is fine.

I've built a few trackbikes but never a converted road bike single speed!

Reverse dish is common on conversion wheels to keep the chainline in check. This is done all the time.

Chainline trumps symmetrical wheel

jim

Cool, my thoughts exactly!

Got any BB spindles around? I think it would be better to replace the spindle for a shorter one then dish the wheel

Spacers on the Left, and try to keep the chain line as close to the frame center as possible. Unless you're climbing the Alps, Lance, you should be OK.

I assumed this was a one-piece crank and therefore there was no adjustment to the chainline up front. If there is an easy way to alter the chainline up front, then bring it in as close as possible to reduce the amount of dish you need out back.

jim

... or just leave the 5-speed freewheel in place and put the chain on the 3rd or 4th cog.

Well never had a freewheel when I've had it. This was a frame I bought many years ago, then found a better, complete bike a couple years ago. I'm not really a hipster, but I wanted to build something up to ride around the neighborhood doing errands that no one would steal: at least if they do, nothing to cry about. I bought a 10. pair of BMX hubs on ebay, a 9. cartridge bottom bracket and some cheap rims from Nashbar, and a 14. freewheel. Everything else is from my stash of junk; Japanese as I don't use it too much. Goofy stem that came off my son's old bike, Sugino crank down to 1 chainring, a pair of flat handlebars, grips from a 40s cruiser, some Dia Compe calipers and levers. Hopefully I can find a seatpost that fits and an old leather seat. I think I have some old flat Lyotard pedals somewhere.

I did buy new tires and tubes yesterday...

Might even throw on fenders, a rack and a kickstand!

I did put the spacers on the left of the hub, looks like it should work well; I may move the chainring from the outer to inner postion for better chainline too. I want to have the freewheel and mount a chain before I finalize the wheel and true it up.

Sounds like a plan.

And do put the chainring on the inside of the spider if you can stand the way it looks that way. (Some don't like it.) The more inboard you can get that ring up front, even putting spacers between the spider and the inboard ring, the less dish the wheel has to have. And the less dish, the stronger the wheel. And easier on the axle. Depending on how the chainring and chainstays play together, you might even get it to have no dish at all. And some singlespeed freewheels are assymetrical so you might even buy another mm or two there to avoid dish.

jim

+1 on chainring to inside. i bet you can get that puppy set up with no dish. it does make for a stronger wheel. I'd shorten the bb before I dish the wheel. $12 for a un25 (or something) at the lbs should do you fine.