Ok I have tried truing the sprocket and think it may be warped . Anyway the thing never fit too well around the coaster anyway. The bike is a Cranbrook from Wallymart and on the coaster brake it says Falcon and CE-E11 . So the question is what size hub adaptor will work on this thing. Pirate has one but cannot reach them so give me a little shove in the correct direction and as always thanks. gphil
Sprocket adaptor
- Thread starter gphil
- Start date
Regardless of what anyone says about fit, you can only be sure by measuring the diameter of your hub, yourself. This will require either an outside micrometer or a digital or manual caliper. The measurement MUST be EXACT. That means down to the thousands of an inch (or millimeter if you use metric measurements).
Take your measurement and compare it with what the supplier says is the inside diameter of his adapter. If he advertises an adpater for your particular hub it is a good bet that it will fit. The guys who advertise here on the forum know what they're doing.
If you're looking at an adapter from ebay or another source you'll want to confirm the inside diameter of the adapter before you buy, or take a chance.
If the adpater is too big, and it only takes a few thousands, then it will slip and cause you as much problem as a bad rag joint. You'll also want to make sure the adapter fasteners are torqued to the manufacturer's recommendations. Too loose and it will slip. Too tight and you run the risk of stripping threads.
I feel it is a good idea to buy the adapter and sprocket as a set. That way there isn't any doubt about the sprocket working with the adapter and no redrilling will be necessary.
Good luck.
Tom
Take your measurement and compare it with what the supplier says is the inside diameter of his adapter. If he advertises an adpater for your particular hub it is a good bet that it will fit. The guys who advertise here on the forum know what they're doing.
If you're looking at an adapter from ebay or another source you'll want to confirm the inside diameter of the adapter before you buy, or take a chance.
If the adpater is too big, and it only takes a few thousands, then it will slip and cause you as much problem as a bad rag joint. You'll also want to make sure the adapter fasteners are torqued to the manufacturer's recommendations. Too loose and it will slip. Too tight and you run the risk of stripping threads.
I feel it is a good idea to buy the adapter and sprocket as a set. That way there isn't any doubt about the sprocket working with the adapter and no redrilling will be necessary.
Good luck.
Tom
Or you can get really ambitious and make a brake arm. Oh hay it just so happens I'm in the middle of posting a "how to " coaster brake arm tutorial if this interests you than follow along...
http://motorbicycling.com/showthread.php?p=554850
Sprocket adaptor is the way to go.
http://motorbicycling.com/showthread.php?p=554850
Sprocket adaptor is the way to go.
Of course you can always just buy a sprocket adapter that actually clears the brake arm with no modifications.
Thanks guys always get good response form this forum. 2-door thanks for all your input always welcomed. I remember trying to enlarge the hole on the sprocket but got it a little off. I think the idea is to try and keep these things cheap, less costly, and enjoy the hobby. I do plan to put some good money in a build one day but for now miss my local short transportation and the head turning. lol gphil
Mass, that was a eyeopener on the brake arm. Originally I test , bent , test bent etc until I got a fit. It never was good. Now I have a welder soooooooooooo . Head to the junk part bikes and see what I have. I have a 42 tooth sprocket and would a 40 or what ever really make that much difference? Want a cruiser that will maintain a good speed and still climb hills. Sort of hilly here in this little town. You get my point I bet. Reason I ask is my now sprocket may be warped slightly and will have to get a new one. gphil
Contrary to popular belief, the center hole in the sprocket is not critical. It can be oval, egg shaped or square. The important things are if it clears the hub and the teeth of the sprocket are concentric with the hub. You don't need a machinist or a lathe or a mill to open up the sprocket hole. A rotary file in a drill, a Dremel tool, even a rat tail file will work. Just as long as the teeth of the sprocket run true when the wheel is spinning is all that is important. The center hole is just a hole. Not an alignment issue.
As for the coaster brake arm clearing, you need to put a "Z' bend in it to clear the sprocket bolts. It usually doesn't take much bending to get the required clearance.
Warped sprockets aren't that uncommon. They can be straightened with a flat surface and a mallet. Just don't damage the teeth. I've used a large Crescent wrench to bend a warped sprocket back into shape as well as a hammer. Just keep checking it against a known flat surface as you work. However warped sprockets are far less common that inconsistancies in rubber thickness. If they aren't the same thickness across their surface they can make it appear the sprocket is warped. Check the rubber parts.
Tom
As for the coaster brake arm clearing, you need to put a "Z' bend in it to clear the sprocket bolts. It usually doesn't take much bending to get the required clearance.
Warped sprockets aren't that uncommon. They can be straightened with a flat surface and a mallet. Just don't damage the teeth. I've used a large Crescent wrench to bend a warped sprocket back into shape as well as a hammer. Just keep checking it against a known flat surface as you work. However warped sprockets are far less common that inconsistancies in rubber thickness. If they aren't the same thickness across their surface they can make it appear the sprocket is warped. Check the rubber parts.
Tom
Leaving your wheel untrue will still throw the chain. I think it would be much easier to spend the $20 to get your wheel trued at a bike shop and just use the rag joint. Bike shops can work some miracles on very untrue wheels.
