I'm nearing completion on my first build and my last step is to fit the drive sprocket and chain but I just found out the the center hole in the sprocket is not a large enough diameter to fit over my coaster brake hub. What are my options? I'd like to retain this rim/hub set because they are the original painted rims that came with my 50's Columbia Rambler and give it a cool vintage look. Does someone make a sprocket with a larger center hole? Thanks for you help...
My rear drive sprocket doesn't fit over my hub. HELP!
- Thread starter Meccanica
- Start date
if you have a local machine shop,they could possibly machine the hole larger for fairly cheap. take your hub in have them measure it to get it just right.
i had a spindle machined down for 30$
i had a spindle machined down for 30$
Another option would be a sprocket adapter that bolts on to the rear hub from Pirate Cycles. They even ask you what your hub size is before you order. My next MB will have one of these because my rear wheel is ruined now because of that bolt on rag joint. I have tightened the spokes 3 times now and the wheel still wobbles...Dan
Or trim the dust cover? I've never had to open the center of a sprocket. For me much easier to just trim the dust cap?
Thanks for the tips everyone. I ended up stopping by a local machine shop today with the sprocket and the dust cap and had the open up the center hole. When I asked him what he would charge he said to come back in an hour with a large Dunkin Donuts coffee and we would call it even! Can't beat that 
OK, just when I thought my problems were solved a new one has popped up. The three semi circular retainers that fit over the bolts on the inside of the rear sprocket don't match up at all with the holes in the sprocket or rubber pieces that were provided in the same kit. I guess they made an error and send me the retainers from a different size sprocket? So, can I just leave those pieces off and bolt this thing all together without them or and I screwed?
NO! Do Not Install the sprocket without the metal plates.!!!!!!
Are you sure they don't match the sprocket holes? Have you actually laid them on the sprocket to check? Not matching the holes in the rubber is normal and is why some people have so much trouble installing the sprocket but I've only heard of one instance where the plates did not mate up with the sprocket holes.
Check again and get back to us. If in fact the parts do not match then contact your seller and demand replacement parts.
Tom
Are you sure they don't match the sprocket holes? Have you actually laid them on the sprocket to check? Not matching the holes in the rubber is normal and is why some people have so much trouble installing the sprocket but I've only heard of one instance where the plates did not mate up with the sprocket holes.
Check again and get back to us. If in fact the parts do not match then contact your seller and demand replacement parts.
Tom
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Oh yeah, I laid them on the sprocket and it wasn't even close. I guess I'm contacting Boygofast to complain. Wish me luck!
HI,
If you can't (or don't want to enlarge the center bore yourself) we can make sprockets with any size center bore you specify...Generally, coaster brakes require a 1.75 inch center bore.
Hope this helps you.
Good luck on your build.
Andrew
If you can't (or don't want to enlarge the center bore yourself) we can make sprockets with any size center bore you specify...Generally, coaster brakes require a 1.75 inch center bore.
Hope this helps you.
Good luck on your build.
Andrew
Be sure to take it around to show him once you have it together.Thanks for the tips everyone. I ended up stopping by a local machine shop today with the sprocket and the dust cap and had the open up the center hole. When I asked him what he would charge he said to come back in an hour with a large Dunkin Donuts coffee and we would call it even! Can't beat that
That's like when I needed my exhaust pipe bent a little.. stopped by a local guy's auto shop with a couple of twenties in my pocket and asked him if he could help me out. He asked if I could drive, I told him I can drive just about anything with wheels and a motor. Ten minutes later I'm following him back with a car from somewhere that did paintwork for him. Fired up the torch when we got back to the shop and had it done quick and easy. (Well, except for when he cut the oxy and acety lines to the torch off accidentally... He was telling a story and talking with his hands.. with a lit torch in one hand, waving it around...)