Disc brake sprocket mounting adapter, MZ Parts


New Member
Jun 8, 2017
I thought maybe mounting the rear sprocket on the disc mount would be a better mounting than either the rag joint or the hub adapters. I got a 38T and 40T since I wanted just a little more top speed from my 49cc 2stroke.
I probably should just gotten a hub adapter for my old rims. this sprocket setup from MZ Parts Miami really is not great. there is no provision to adjust sprocket alignment other than what I've come up with.

out of the box, the sprocket sits flush to the adapter, resulting in bad alignment and it threw the chain in 10ft just walking the bike. scratched head in disappointment. remount old non-disc wheels. puzzle over the adapter. put disc adapter on my lathe and take off .020 of the back inside mounting flange and reinstall with the garbage 10mm barrel nuts it comes with. it threw chain in 11ft lol. curse for a minute,,
rethinking it, I realize the offset has to be more than .100. I could machine off maybe .060 but thats not enough and those clinch bolts or whatever are still garbage. what even is that bevel on the sprocket? its for nothing except maybe lightening up things, but as is, the disc adapter does not cover them totally. dirt can get in and you aint cleaning it there once installed.
phase 2, getting the idea I can use those bevels for some tapered bushing (impossible to find perfect off the shelf dimension) so I decide a beveled faucet washer will help in there even if a little smaller and with 20mm M6 bolts, I can add a couple washers to offset the sprocket more.
to make it short, 2 was not enough, so add the neoprene washer and 3 steel ones gave me the .105 offset minimum I needed.
pics show my setup
has anyone did something different to offset the sprocket closer to the spokes, experience with MZ's garbage adapter? Im thinking about molding my own polyurethane bushings to sit in these bevels. cushion the chain shock force and offset the sprocket same time.