If I ride cotterless cranks without the bolts in, will they eventually fall off?

Question

I ask because using my old crank extractor with damaged threads, I managed to completely stip the threads of a pair of cranks on one of my bicycles. Now I can't remove them. The only way I can think of to get them off would be to ride them without the nuts in until they loosen and fall off - will this work?

Answer 1

It is usually possible to hammer them off from the back using a long, blunt chisel and a hammer, a bit of heat around the crank arm helps, I have done this many times, care is needed to avoid excessive damage especially if you intend to reuse the crank.

Answer 2

I would get a small gear puller and use that.  Just s***w the crank bolt in far enough to push against with the puller.

Answer 3

the crank arms are likely aluminum and the axle is steel.  there is a reaction that takes place that basicly welds the arms on the spindle.  this is likely why you couldnt get them off, and if this is the case they arent going to come off.  more than once we had to cut such cranks off when i worked in the bike shop.  all you can do when this happens is to cut through the spindle, which is no easy task.  then replace the crank and bottom bracket.

if you hadnt stripped them you may have tried soaking in penetrating oil and heating the arm to help free it, but now that they are stripped you are in trouble.  a regular puller like a car might use doesnt get a good bite on the smooth, rounded arms of a crank and wont hold well enough to get it off in my experience.  goodluck, but i believe your only option is going to be to cut it apart and replace it.

Answer 4

You can, and they most likely will loosen up and come off, but it's not the best idea.  If you're vigilant and stop riding when they loosen, you should be ok, but it's very easy to damage the crankarm if you ride it when it's loose.  Then again, since the threads are stripped, maybe this doesn't matter and you can just go for it.  

Another thing you can try is using an automotive ball joint remover (aka "pickle fork") or a homemade wedge made from plastic or wood that you can hammer inbetween the crank and the frame.  Here's a link to the automotive tool for reference:  http://www.harborfreight.com/cpi/ctaf/Di...

You could also try a standard 2-jaw puller like this: http://www.wttool.com/product-exec/produ...

Over here you can buy some cruddy China imported tools for very cheap, but I'm not sure if you guys have those same products available or not.  You may also be able to rent them from a parts store.   Hope this helps you out...good luck!

(p.s. Crank extractors are one of those bike tools that you definitely want to spend the money for a good one made of quality tool steel.  Park, Pedros, and Tacx are high quality for sure.  Also, always be sure to snug up the puller into the crankarm threads with a wrench before you start to pull.....goes a long way toward avoiding damaged threads on either part.)  

Answer 5

Your thought might work, but best case it would come off when you don't expect it to.  Worst case, you damage the spindle or hurt yourself when the crank gives way.

Like miggity said, get a 2 arm puller.  It will absolutely work.

Answer 6

I have a resoltion for you. Get a small 2 arm gear puller. They are readily available at most auto parts stores.

s***w a bolt partially into the spindle. Wrap the puller arms around the crank arm, center the puller spindle onto the bolt, and turn carefully.

Once you see the arm break loose remove the puller and the bolt, then take the arm off.

Riding without bolts might work but I'd hate to be 10 miles from home when it happens!

Answer 7

You need to start a blog Liam. Something like "The trials and tribulations of Liam and his bikes", lol

Answer 8

Why not bang them out with a screwdriver and a hammer?

Answer 9

the best way i found to deal with those is to take a hammer and tap the crank arm until it loosen.  tap the arm as close as you can to the axle. the axle should be stronger then the crank arm. It will work.

When i had a shop i put the bike in i vice while the bike was sideways with the vice not tightened all the way.  then got a bar of some type and used it as a blunt chisel angled on the crank arm near the vice.  And pounded away.  

Do not ride the bike without them in place.  there is no knowing when the arm will come off and you get your jewels broken just when you think that you have been riding and they wont come off.  OUCH