Mechanical (non spoke) adapters

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JackFlorey   100 kW

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Mechanical (non spoke) adapters

Post by JackFlorey » Apr 05 2021 2:49pm

Has anyone seen non-spoke-based adapters for large motor/small rim combinations? For example, if you wanted to do a Grin all-axle hub motor on a 16" rim, there's no way that you could do that with spokes. But it would likely be fairly easy to do either a machined or bent-up sheetmetal adapter that would mate to spoke holes on the rim and the spoke holes on the hub motor. (Might have to drill out the hubmotor holes a bit.

markz   100 GW

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Re: Mechanical (non spoke) adapters

Post by markz » Apr 05 2021 3:42pm

I have actually thought about doing just that with my Leaf 1500W because the cast rim Leaf sells only fits the narrower 1kw. The cast rim is attached to the magnet rim. Mine would have been 26" rim instead of your 16", so longer "spokes" for me. I wonder if that link is 18" motorcycle diameter or bicycle diameter.



Problem is getting the right length of material from the spoke flange holes to the rim spoke holes to have a centered rim to hub.
You'd need a rim that would be non eyelet rim. Good thing is you could swap out the rim only if the rim were to be damaged, unlike a cast wheel as linked above. Yeah I still ponder it every now and then. Probably best to make a jig to center the hub to rim, figure out your "spoke" material and try it out. I'd sure be interested in hearing how you go about building it.


JackFlorey wrote:
Apr 05 2021 2:49pm
Has anyone seen non-spoke-based adapters for large motor/small rim combinations? For example, if you wanted to do a Grin all-axle hub motor on a 16" rim, there's no way that you could do that with spokes. But it would likely be fairly easy to do either a machined or bent-up sheetmetal adapter that would mate to spoke holes on the rim and the spoke holes on the hub motor. (Might have to drill out the hubmotor holes a bit.

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MadRhino   100 GW

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Re: Mechanical (non spoke) adapters

Post by MadRhino » Apr 05 2021 4:50pm

No such adapter available. You’d have to make it. There are some adapters for non flanged motors though, hard to find but they exist. Still, you’d have to cut off the spoke flange and shave the rotor external size to exact dimension.

I would lace it. I mean, not an easy lacing job but it can be done, preferably using a wide rim with offset drilling. The motor flange is 214mm and a 16’’ bicycle rim ERD is 305mm.
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Chalo   100 GW

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Re: Mechanical (non spoke) adapters

Post by Chalo » Apr 05 2021 6:47pm

markz wrote:
Apr 05 2021 3:42pm
The cast rim is attached to the magnet rim. Mine would have been 26" rim instead of your 16", so longer "spokes" for me. I wonder if that link is 18" motorcycle diameter or bicycle diameter.
The specs say it's 372mm in diameter, which is about 14-5/8". So not an 18" motorcycle rim. 18" bicycle rim like for a preschool child.
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