20" mag wheel

[Hugh]

I have a Magic Pie with external controller currently mounted on a 26" rim. Golden Motor sells a 20" mag wheel. Is it possible to put my Magic Pie motor into the 20" mag wheel?

[Bikemad]

Hi Hugh,

I don't know which side covers are required to properly fit the the 20" cast rim/motor ring assembly, but I would expect it to use the original MPI right hand side cover, which is slightly larger in diameter than the MPII, MPIII, MP4 and MP5 covers, as these later versions were slightly smaller in diameter so they could fit within the wider motor ring which was first introduced on the MPII spoked wheels.

I think the later right hand side covers (with a smaller outer diameter) will still fit the cast wheels, but they only have half a hole for the cover retaining bolts to tighten against.
This "half hole" is far from ideal, as it applies a very uneven force upon the underside of the heads of the Allen bolts, causing the bolts to bend away from the cover mounting holes as they are tightened.

Alan
 

[Hugh]

Thanks for the reply. I have now taught myself how to true a wheel and replaced all the bent spokes on the 26" wheel. When I saw the cast rim the thought came that no spokes needed could be a good thing. And since I do like to build trikes it wouldn't be too hard to convert my yellow one to 20" wheels. But for now there will be a spoke wrench in the toolkit and the Magic Pie wheel spokes will get checked often for tightness. I did get a few hundred km's on it before it became a problem so hopefully it will be better now. Also I let a friend take the trike for a ride and it was pointed out to me he is a mountain bike racer and was prob going at his usual pace in a rough area. The trike is heavy and unsuspended, I go slow over rough roads and bumps, it's possible he did not, that may have contributed to the spoke loosening