20" three speed???

[hoof]

My boy had a little trouble making the hills we were on today, and I was thinking a three speed might help him (he has a non-ratrod Trek Jet 20" BMX). Does anyone know of a three speed 20" wheel I could get? Would it work to get a SA and just lace it to a 20" rim? I forgot to add that it is a coaster brake bike.
Thanks,
CHAZ

My boy is only 6, and we did 8 miles today, so I guess he deserved to be tired!

 

[CCR]

lace one in, s/a 3speed hubs are great and they made coaster versions too, ive also had a shimano 333 three-speed coaster that gave me no trouble either.

 

[Crassly]

You could lace either a SA or a Shimano 3 speed, but the difficulty will be finding a hub with the correct number of spoke holes for a 20 inch rim.

 

[CCR]

i snagged a couple "sun" 36h 20" rims from my lbs for $20/both a little while back. check your Messages too, sent you something.

 

[michaelscycles]

I have done this with several bikes. I have been using 36-hole chrome steel rims. Great way to learn how to lace a wheel too.

Check the gearing he is running now. You may want to put a bigger rear on the hub, or change the front to a smaller one. If not, he will still have a problem with the hills, just faster on the flats in 2nd and 3rd gear. I usually put a 22 tooth on the rear.

If you need any of the parts, hub, sprocket, spokes, or wheel, let me know. I can hook you up with new stuff for a reasonable price.

Good luck

Mike

 

[NLCTVWguy]

A 36 hole rim and a common 3-speed hub from a lightweight will work, as long as it is also a 36 hole rim. Look closely- even some Columbias and other "American" brands used 40-hole English 3-speed rims. Western Flyer did as well.

Schwinn lightweights (Breeze, Speedster, etc) all used 36 spoke rims, so if you find a 36 hole 20" rim, this will lace up. The 40's are pretty much useless to building a 20" bike.

If you have 28 hole rims, very common in kids bikes, you'll need a hub that matches. I have a couple that came from Schwinn 3-speed Fairladys and Stardusts, not real easy to find but they are out there, and usually not worth a whole lot. There were 3-speed Stingrays with S-2 rear rims, and these rims are somewhat expensive but usually because of the S-2 hoops. Any 28-hole rim can be laced to these hubs- they're usually dated 66 to 71, and came with S-2 (20x2.125), S-7 (20x 1-3/4") or on the Fastback/Stardust the S-5 (20x1-3/8") rims.

The coaster model was sold in the late 70s on a few Stingrays and as the only option besides a single speed for the girls bikes. There are both Sturmey 3-speed coasters and Shimanos out there- and be advised they do not mix and match, the cables are close in size but different thread.

--Rob

I have done this with several bikes. I have been using 36-hole chrome steel rims. Great way to learn how to lace a wheel too.

Check the gearing he is running now. You may want to put a bigger rear on the hub, or change the front to a smaller one. If not, he will still have a problem with the hills, just faster on the flats in 2nd and 3rd gear. I usually put a 22 tooth on the rear.

If you need any of the parts, hub, sprocket, spokes, or wheel, let me know. I can hook you up with new stuff for a reasonable price.

Good luck

Mike