Lacing hub motor onto new rim

[joshseitz]

I am about to build a new wheel around my Amped geared hub motor (36 hole). It came on a 700C rim (29er), but I'm converting it to a 26" unit for a different bike.

FIrst off, the existing wheel came with 12 gauge spokes. It appears that 12 gauge spokes are quite rare, as are rims designed to handle them. Does anyone see an issue with going to 14 gauge spokes? 14 gauge is not uncommon on heavy-duty downhill bikes, even with only 32 spokes, so I can't imagine it would be an issue here. If anyone feels otherwise, please chime in.

Spoke length. SInce the motor is considerably larger than most standard hubs, does anyone know how long the spokes should be? I could certainly make a rough measurement, but I'm not exactly sure from what points I should measure.

thanks for your input!

[DAND214]

You can start here http://www.ebikes.ca/SpokeCalc.shtml
to figure your spoke lenghts.
As for 14g spokes, no problem, easier to work with and easier to tension.
Good source for cheap good spokes is http://www.danscomp.com/search.php
You can get just about any length in a day. I've used the Sapim 14g ss and black ones with no concerns. I always get extras jut in case, They are so cheap it's cheaper to spend a couple bucks now than ordering a couple later if you need them.

Dan

[biohazardman]

Nothing wrong with quality 14ga spokes many run them. You should be able to get the 14ga spokes and rims local. Many of the Chinese kits come with what looks like 12ga spokes but the are really low quality steel units thinned down to 13ga where they meet the nipples. I broke lots of these with my first build. I run the twelve gauge Sapims now but as you have said it is not easy to find rims for them. I managed to get rims predrilled for them from my local bike shop in Gresham Oregon. Took my motor into the shop when the rims I ordered came and they told me what size spokes I needed as well. Bike shop supplied some others I got from johnrobholms here on the forum as well as Danscomp mentioned above.

http://greshambike.com/

[joshseitz]

Thanks for the rapid response! With respect to the spoke length calculator, my hub motor isn't listed. It appears that if I manually enter the following info, i'll get the answer I need? Can you elaborate on a few of the dimensions that it asks for?

Effective Rim Diameter INSIDE OR OUTSIDE RIM DIAMETER?
Hub Flange Diameter TOTAL DIAMETER, OR FROM HOLE CENTER TO HOLE CENTER?
Flange Spacing mm
Diameter of a spoke hole
Cross pattern cross SINGLE OR DOUBLE CROSS>
Number of spokes

[full-throttle]

http://sheldonbrown.com/rinard/spocalc.htm



1 cross for bigger hubs, 2 cross for smaller ones
36 spokes

[joshseitz]

thanks!