Sprocket adapter to wheel with 68 spokes?

......most likely getting another wheel.

All the sprocket adapters I've seen have 3 bolts that go through the spokes to attach to the sprocket (rag joints use 9 bolts). So, the spoke count of the wheel has to be evenly divisable by 3 (adapter) or 9 (rag joint).

68/3 = 22.66. 68/9 = 7.555. Both of those = won't work.


How about using a shift kit? Then you could use your 68 spoke wheel........

For 68 spokes, you would need either 4 or 17 evenly spaced bolts to go thru the spokes to make any kind of adapter work. You could do this by getting an undrilled sprocket and taking it to a machine shop where they can drill the holes evenly spaced, then make up an inner ring, drilled, then cut into 3 segments like the typical rag joint by using 2 rubber rings that are drilled the same way.
If you can mark and drill the holes yourself, you could save some money, but if you're trying to drill 17 evenly spaced holes thru a steel sprocket, it's going to be time consuming to say the least, you could probably drill 4 evenly spaced holes, but a rag joint wouldn't be very stable with that few holes. Otherwise, you would have to have a sprocket adapter custom made similar to the manic type but that would be quite expensive at the machine shop.

The cheapest and easiest solution would be to get a 36 spoke rear wheel, but it can be done if you got the resources (or money) and want it bad enough.

Sounds like a great opportunity to learn how to lace and true your own rims.

If you've got 68 spokes, I'm guessing they are laced radially? If so, that's not ideal for a motor driven wheel since the tendency of the wheel is to "wind up" when you apply torque to the hub. This stresses the spokes and can lead to breakage. They are OK for pedaling since they are intended for mellow cruising leg power, rather than hooking a motor to. So even if you can do it, I'll echo davezilla and suggest lacing a 36 spoke hub/rim up for the rear for longevity and durability.

I was thinking it might be possible to bolt a flat ring to the manic mechanic three hole style then drill that ring to a pattern that fits thru the spokes and drill the sprocket too match. If it works it would be solid. I mug be doing it myself soon then I will know what it takes.

Of course... if they only made a 68 spoke rim set up with a disc brake you could just use a hat adapter or a sprocket drilled to mount to the disc brake hub and be done with it...

I can also agree about the radially laced spokes... not good for applying torque to... pretty much not that good over bumps either since there's not a lot of metal between the spoke and the edge of the hub, there are more than a few manufacturers who will void any warranties on their hubs if they are laced radially.... really about the only things radially laced rims are good for is appearance...

There are some radially laced motorcycle wheels

dtv5403 said:

There are some radially laced motorcycle wheels

Click to expand...

For sure there are, buy you mainly see them on fronts where you don't have the motor power and the spokes, nipples, rims, and hubs on a motorcycle wheel are all seriously beefed up over a typical bicycle wheel with 12 or 14 ga spokes. Even on pedal-only bikes it's not common for a radial rear, on roadies it's gotten extremely common up front but 2x is usually the lowest you'll see on a rear. Not saying it can't be done, just that it's not ideal for powered use.

Really, that's the best bet... and the 12 gauge spokes will last a lot better than the thinner 14 gauge ones... I got 2 front rims with 12 gauge spokes and I'm thinking about harvesting those off the spare rims to lace my bike's rims with simply because they're considerably stronger. I've gone pretty fast on those wheels and 14 gauge spokes And with the rag joint setup instead of the good sprocket adapters, but I've seen enough and heard enough horror stories to motivate me to re lace the rims I got with the thicker spokes before something I don't want happens at above 40mph...