Internal Gear Hubs - rear sprocket ate dust cover

Hello friends,


i have a Shimano 3-speed, internal gear hub with coaster break. Its sweet, now, to motorize a bicycle with a china gurl or HT (frame mounted 2-strokes) you would have to mount a sprocket on the back, and on what we llike to call "the dust cover" this will most likely have a coaster break arm.

Now be carefull of the following details

1.The sprocket has to clear the dust cover enough so you can ensure they never ever touch!

2. The bols that hold the sprocket need to be flat headed to clear the coaster break arm.

heres some pictures


What happened to me: after 150 miles the sprocket was not as aligned as i thought, the chain came off into the spokes and attacked the sproket!! 3 nuts lost wably sprocket ans now i see this...i think it could be that i placed the coaster break arm onto the upper frame bar, and the great preassure the motor was expressing thru the spokes...

Attached Thumbnails

   

i took off my dust cover so my sprocket would fit. and i used a metal spacer between sprocket and wheel so chain would line up and not touch tire. my coaster brake arm had plenty of clearance between bolts and arm with no modifications. my tensioner keeps my chain lined up with the rear sprocket and so my chain always stays on.plus a used a bolt and 2 hose clamps to hold the tensioner in place.