jack0174 Posted February 6, 2009 Report Share Posted February 6, 2009 I have a little problem.Basically there is a sprocket stuck on my cranks, they have been down the bike shop for 2 weeks and the bloke said it wont budge.So is there any alternate methods of getting the sporcket off. BTW i dont want the sprocket just the crank. Quote Link to comment Share on other sites More sharing options...
Jack Chinnery Posted February 6, 2009 Report Share Posted February 6, 2009 I have a little problem.Basically there is a sprocket stuck on my cranks, they have been down the bike shop for 2 weeks and the bloke said it wont budge.So is there any alternate methods of getting the sporcket off. BTW i dont want the sprocket just the crank.Sorry, Dont want to sound like a drag. But have you checked the wiki? Quote Link to comment Share on other sites More sharing options...
jack0174 Posted February 6, 2009 Author Report Share Posted February 6, 2009 Youre right bit stupid of me. Quote Link to comment Share on other sites More sharing options...
Jack Chinnery Posted February 6, 2009 Report Share Posted February 6, 2009 Youre right bit stupid of me.Nahh your not stupid, Just check the wiki next time But then if you need any help post it in the this thread Quote Link to comment Share on other sites More sharing options...
bigamac Posted February 6, 2009 Report Share Posted February 6, 2009 Well if you dont want the sprocket get a hacksaw and start cutting. Just dont catch the threads. Quote Link to comment Share on other sites More sharing options...
16 years later Posted February 6, 2009 Report Share Posted February 6, 2009 Hi, you could try heating it. Stick it in a vice, heat round the sprocket, on the thread with a blow torch, then use the chain whip and it should come off. The heat will make it expand and it should then come off. Quote Link to comment Share on other sites More sharing options...
Muel Posted February 6, 2009 Report Share Posted February 6, 2009 Wrap a chain round the sprocket, put the chain in a vice and lamp it up, then put a big bar on the crank arm and it should undo easily enough. Quote Link to comment Share on other sites More sharing options...
Sidehop Stuart Posted February 6, 2009 Report Share Posted February 6, 2009 I took mine to my local back shop and they cut 2 sides of it off to make it square to fit in the vice.Then they got a long pole and un-tightened the sprocket. It's that easy. Quote Link to comment Share on other sites More sharing options...
forteh Posted February 6, 2009 Report Share Posted February 6, 2009 (edited) Hi, you could try heating it. Stick it in a vice, heat round the sprocket, on the thread with a blow torch, then use the chain whip and it should come off. The heat will make it expand and it should then come off.May not work, the aluminium crank will expand faster than the steel sprocket and likely wedge it on tighter If you have a decent sized vice that is bolted down to a solid bench/the floor then you should be able to hold the sprocket with some chain, stick a decent sized steel pipe over the crank arm and twist it off.See this handy autocad sketch that I did a little while ago (obviously replace wheel with crank arm )edit: waay too slow, muel got in there whilst I was searching for that acad sketch - bah! Edited February 6, 2009 by forteh Quote Link to comment Share on other sites More sharing options...
andyb Posted February 6, 2009 Report Share Posted February 6, 2009 Im having this very issue with a rear wheel sprocket, its a right pain in the arse. Quote Link to comment Share on other sites More sharing options...
Adam-Griffin Posted February 6, 2009 Report Share Posted February 6, 2009 (edited) Is it a drilled sprocket ? Can remember someone on here did a guide, think it was Joey B. will have quick search ...Edit: Linky Edited February 6, 2009 by ™Adam-Griffin™ Quote Link to comment Share on other sites More sharing options...
Cookyboy Posted February 6, 2009 Report Share Posted February 6, 2009 air chissel will do it Quote Link to comment Share on other sites More sharing options...
andyb Posted February 6, 2009 Report Share Posted February 6, 2009 Not drilled unfortunately, its a surly cog, am just gonna grind the thing off. Quote Link to comment Share on other sites More sharing options...
craigjames Posted February 6, 2009 Report Share Posted February 6, 2009 or get two blocks of wood, clamp the sprocket between the two blocks in a vice. get some leverage on the end of your crank arm and turn it off. Quote Link to comment Share on other sites More sharing options...
andyb Posted February 6, 2009 Report Share Posted February 6, 2009 Thats all well and good but mine is on my wheel. Quote Link to comment Share on other sites More sharing options...
Henrik Y Posted February 8, 2009 Report Share Posted February 8, 2009 (edited) I had the same problem. Tried wood blocks but that just got into toothpicks. I took the thickest chain that I had and wrapped it around the sprocket and clamped it in the vice as shown in earlier post. Then I put a larger nail trough the chain on the other side to stop it from slipping. Then I had a friend to hold the workbench and a 2m long iron pipe on the crank. My weight wasn't enough so I had to jump and pull it and almost cracked the bench. Steady workbench with a large vice and much force is what you need. But if you are lucky it may go easier then it did for me, I didn't grease it when screwing it on Edited February 8, 2009 by Henrik Y Quote Link to comment Share on other sites More sharing options...
JonMack Posted February 8, 2009 Report Share Posted February 8, 2009 I've been fortunate and have always managed to do it no probs with a chain tool and a 3ft length of steel pole. Quote Link to comment Share on other sites More sharing options...
jack0174 Posted February 9, 2009 Author Report Share Posted February 9, 2009 Is there any way to do it without a vice as i dont have acess to one. Quote Link to comment Share on other sites More sharing options...
psycholist Posted February 9, 2009 Report Share Posted February 9, 2009 Park a car on the pedal and get a very long chain whip around the sprocket and lever it off that way. I'd advise trying a different bike shop to see if they can do it if the last one you tried failed. If the sprocket is junk I'd take an angle grinder to it and cut the sprocket from each side to just short of the crank threads and break it off with a chisel. Quote Link to comment Share on other sites More sharing options...
jack0174 Posted February 17, 2009 Author Report Share Posted February 17, 2009 :@ Still cant get it off even snapped 3 teeth in the process of trying, is there anyone i could send the crank to to try and get it off please, pm me if you think you can get it offand im sure we could sort something out. Quote Link to comment Share on other sites More sharing options...
Mike W Posted February 17, 2009 Report Share Posted February 17, 2009 STOP!Hammer time Quote Link to comment Share on other sites More sharing options...
Dave Anscombe Posted February 17, 2009 Report Share Posted February 17, 2009 steel sprocket.......alu crank arm.....i still heated it up twated it with a hammer came off easy as Quote Link to comment Share on other sites More sharing options...
jack0174 Posted February 17, 2009 Author Report Share Posted February 17, 2009 (edited) Tried heating it up yesterday but still nothing,then later on yesterday i got a small spanner that put the open end on one of the sprocket teeth and hit it with a big lump hammer for about an hour didnt work either, but not tried heating it up and hitting with a hammer will try that now. Edited February 17, 2009 by jack0174 Quote Link to comment Share on other sites More sharing options...
jack0174 Posted February 17, 2009 Author Report Share Posted February 17, 2009 Just tried heat + hammer but i couldnt find my blow torch can thingy so i used a can of lynx and a lighter but still nothing. Quote Link to comment Share on other sites More sharing options...
Ben John-Hynes Posted February 17, 2009 Report Share Posted February 17, 2009 :@ Still cant get it off even snapped 3 teeth in the process of trying, is there anyone i could send the crank to to try and get it off please, pm me if you think you can get it offand im sure we could sort something out.You live in Birmingham!?I MAY be able to gt it off... Quote Link to comment Share on other sites More sharing options...
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