musical_wheels

Hi Guys,

My sis asked me to overhaul her old mountain bike (an apollo make) which she has has had in storage for a few years.

I've given it a thorough cleaning, regreased the bearings on the wheels etc.

Using her money, I have bought several new replacement parts, mainly for the drivetrain (chain, freewheel, chainwheel, pedals).

Everything is ready to be replaced except for one major setback... BIG!!!!!!! problem is removing the old chainwheel (Make is 'Thum'). It is extremely stubborn and will not budge! I've tried to use a removal tool but it just wore away the threads on the chainwheel. My local bike store suggested I use a hammer with a strong chisel or large screwdriver. I spent ages today trying that but the chainwheel will still not come off. It's driving me nuts. I don't want to disappoint my sister, especially as she has spent a lot of money on a new shimano chainwheel and other parts.

I've read about a 'crank puller' but I don't really know what that is or if it will help me.

Can any of you guys please recommend a way to take this bleedin' thing off!!! I may end up having to saw through the bottom bracket axle as a last resort!!

Many thanks for any help,

Regards,

P.

JiveTurkey

The name of the crank removal tool is a crank puller. Since you said the cranks threads were ruined, it sounds like you used a crank puller.

Were you able to remove either crank arm?

Don't take offense, but did you remove the nut or bolt that attaches each crank arm to the bottom bracket spindle first?

musical_wheels

I screwed some tool into the crank and used a spanner to turn the other part of the tool, hoping that would eventually force the chainwheel to separate but no luck.

No offense taken, JiveTurkey! Yes I removed the bolts from both crank arms and no, none of the crank arms will budge!!

Homebrew01

Pretty much what my response was going to be. Did you remove the washer under the bolt too ?? That would get in the way of the tool preventing it from going all the way in, and making it easier to ruin the threads..

If the crank bolt is out, I've heard of people pounding it off with a hammer & punch from the back and/or riding around the neighborhood waiting for it to work loose. Why did it need replacing ? Cranksets last forever.

musical_wheels

There was no washer under the bolts. All that can be seen is the crank 'hole' and through that, the end of the bottom bracket axle.

JiveTurkey

The crank pullers can be tricky to use. If the puller isn't opened up all the way first, the outer threads can be prevented from engaging all of the crank threads, making stripping easier. If just the first couple threads were ruined, there might be enough left in there for the puller to work.

If they won't come loose from riding around as suggested above, I'd try letting some penetrating oil seep in between the spindle and crank overnight. With the bike on it's side, put some oil on the inside of the lower crank and the outside of the upper crank and let gravity work it down.

musical_wheels

Sounds like a good idea. Thanks for that!!

musical_wheels

Most of the teeth on the chainwheel are very rusty and a few of them are actually broken off (don't know how.. not my bike).

jccaclimber

If your crank is aluminum some heat (torch) may help, but be aware that you may damage the paint. Assuming it fits, and you're willing to gouge the back of the crank arm, you may be able to fit a two jaw or three jaw gear puller. The auto parts stores will sell them, and may loan them. The local Autozone and Advance both loan pullers. You will probably need the crank bolts 90% of the way in to compensate for the width of the puller though. You can try pounding them out, but you'll need to pound VERY hard to expect that to work, and will probably need to secure the axle as well. Another option is cutting either the crank from the spindle, or the bottom bracket spindle its self. Assuming you are willing to sacrifice the bottom bracket, you can also go at it with an angle grinder. Just remember to use a flap disk instead of a grinding wheel if there is aluminum involved.

jsavage451

check the crank puller you are using, some have a larger diameter bolt that wont fit inside the square taper hole in the crank. if so, all you will be doing is pressing against the crank and not the bottom bracket spindle.