Stripped threads on drive side crank arm -- how to remove?
 

Just in case it matters, it's a square taper BB and there are 3 rings. Am I just SOL, or is there a way for me to pull this stupid thing off?

Loosen the crank bolt and ride the bike for a couple of miles. Hopefully the crankarm will work itself loose from the bb spindle.

Lay the bike down outside and pour a pan of boiling water over the crank arm. This will heat the aluminum and it will expand away from the spindle. While it is still hot, drive it off by holding a piece of wood against it and striking the wood with a hammer.

go to home depot and buy a valve handle puller?

https://secure54.easycgi.com/sealent...ts/5325873.jpg

Three very different approaches..... and the winner is...?......:D

I'd use a puller because I have one. However, Dave's approach should be the winner because it costs nothing and can't do any harm.

I have used a automobile ball joint remover, works great. Place between BB and crank arm and hit with hammer, crank pops right off.

I vote for The Fixer's suggestion, since it will cause the most injury when the rider flails to the ground when the crank does come off, and then has to walk home, possible with the crank still attached to his shoe. How could you even suggest that? :P

In all fairness he said to LOOSEN the crank bolt, not remove it. If the bolt is loose by a turn or less, and the rider is checking to see if the crank is loose as he rides around the block a few times, I do not see the danger. Crank will just wobble a bit, not come off.

Tried the valve handle puller and it didn't work.

Try this, not very elegant, but effective. Find a socket that fits inside the square of the taper. Put it on a concrete floor, have someone hold the bike so the axle end sits on top of the socket, hammer the crank arm off from the back using a flat punch and a BFH.

Hacksaw

Not that it matters, but it is possible to remove an arm with damaged threads. I once worked at a shop that had an old crank extractor that was modifiied for "special situations."

http://www.parktool.com/repair/readhowto.asp?id=136

If the B.B. is cup and cone you can remove the left side crank, lockring and cup...put a crank bolt in the drive side of the spindle....rest the right hand crank against the B.B. cup....strike the bolt with a hammer...should push the spindle out of the crank. Done it a thousand times with good results.

Thanks to San Rensho
 

Putting a socket that fits inside the square taper and setting it on the cement, though not elegant, was EXTREMELY EFFECTIVE! I had tried everything in this forum short of the hacksaw idea. Thanks San for the post on that tidbit...now on to the BB...grrrr.

Worked like a champ. thank you.

too late, I suppose, but what about a good old fashioned wheel/gear/pulley puller? A good auto parts store will have them. I live next door to an auto mechanic business and have gone over there once or twice with my tail between my legs to borrow it. Easy as pie.

Why do all the desperate stuff when there is a readily available and cheapish tool made for just such an occasion?

jim

Jim, your method works as well. At the shop I worked we had a variety of pullers. Sometimes they work, sometimes they dont. Depending on the crankarm and BB configuration you may not be able to get grip with pullers.

All of the above techniques work. Its a matter of choosing the technique that suits your situation.

1. Do you want to keep the arm? If NO then.....I cut them off with a pneumatic carbon cutting wheel or heated them with propane torch and hit them as Dave Moulton mentioned.

2. If yes....try any of the above techniques.

If you want to be ablde to reuse the crank and be able to remove it easily the next time you should find shop that has something like this;
http://www.biketoolsetc.com/index.cg...item_id=SN-CES

I've used these before ans they're great.

that tool costs $150!!!!!!!

a body can buy a pretty nice crank arm for that kind of money.

jim

You don't have to buy the tool, just find a shop that has it. We charge $11.00 for labor and $10 for the parts.

No injury-but a gear puller-ball joint popper might be better
 

I don't see anyway that an adult well enough coordinated to ride a bike, will be injured if he is lucky enough to work the crankarm loose. He is going to be "looking" for loosening of the arm the whole time he is riding; it won't go from stuck tight to flopping off in one fell swoop.Surely he won't be dumb enough to be clipped into it(except with some loose toe clips or half clips.
Still, if he can fit a bearing puller on it, or better yet use a ball joint popper -that would be easier(if he has theses tools).Whenever someone suggest something with a little risk, he is assuming he is dealing with an adult that has managed to survive 20+ years-not a 12 yo kid.
Luck,
Charlie

Your suggestion is a good one. It is even recommended in the Barnett's repair manual. As long as you do it right it will be safe. I'm sure there are people out there that would find a way to hurt themselves while trying the gear puller method as well.

I've seen a lot of riders come in to the shop with a crank arm flopping around because it was loose, they just kept riding, and riding, and riding...... I remember doing the same thing when I first got into riding, it took a long time for the arm to actually fall off.

The tool that was referred to as a "ball joint remover" is called a "pickle fork", and it should work just great. And here's the good news. I recently needed one of these pickle forks to remove a steering stabilizer on my Toyota pickup, and I found that my local Autozone rents them for free. They require a deposit for the cost of the tool, $15, and then they refunded the full amount when I brought it back. There are at least two sizes, one for ball joints and a smaller size for tie-rod ends, so take the frame with you to the store when you go. So call the parts stores in your area and see if any of them have the same deal.

Good luck

I've tried this and it works fine. As mentioned, loosen the retaining nut, don't remove it. It didn't take miles. I have a relatively steep driveway, so I put the bike in a low gear and stood on it hard up the drive a few times.

Anything where you bang, smash, or generally try and muscle the arm off will probably damage the BB as well. I recently used a homemade tool to get the arm off my triple drive side and preserve the BB. Worked like a charm.
If nothing else works I made a tool but it requires drilling 3 holes through the crank arms. I use a park tool and drill matching holes through a large washer.
1) Drill 3 holes through a large steel washer. Select the washer that has a hole that will brace a park tool crank remover. If you can't find one then use 2 washers of different sizes.
2) place the washer over the crank arms and drill pilot holes. Note: depending on the crank arms you may need to use 4 holes.
3) Separate the arm from the part you normally screw into the crank arm and place the washer(s)on the lever arm bolt. screw into the mounting part.
4) Use carridge boles and pass through the washer and the crank arm. secure the nuts on the carriage bolts using washers.
5) Using the washers to brace the park tool turn clockwise to remove the crank arm like you normally would and voila...the arm will come free. Note: the sizing of everything will be important.
Good luck.