sloar 

Went to simply pull the drive side crank off today using the correct puller. It was stuck on pretty tight, but I soon felt it give a little. Then all of a sudden it happened, the puller broke free and stripped out the threads. I used a heat gun and a pickle fork with no luck, I finally had enough and since the crank was toast anyway I broke out the propane torch. Couple wacks with the pickle fork and it broke free. I hated having that happen, even though they were just Blaze cranks they were mint and original to my Trek. Oh well.


And yes, the puller was threaded all the way on.

SurferRosa

Happened to me once too with an nds arm really stuck to the spindle. Also used heat and pickle fork and it finally gave way. At least I got it off and saved what I could.

RobbieTunes

I have to admit I clicked on this thread to view someone else's misfortune.

Sorry. Someone had to say it, brother.
Semper Fi

Hudson308 

HATE when that happens.

USAZorro

Would have happened to anyone who attempted service on that. Mere misfortune, or possibly a previous wrench's mistake. I have a Fuji that has a Mighty Tour crankset that I overtorqued on it. Nobody will be able to get it off without extreme measures. All my fault, but sometimes...

due ruote 

I can make you feel better. I did that to a Deore crank once by forgetting to remove the bolt first. At least I am unlikely to repeat that move.

Russ Roth

I was smart enough to remove the bolt on a deore crank but didn't pay attention to the lack of washer; same result either way and it so sucked. I salvaged the crank by putting the bolt most of the way in and then taking it for a bumpy ride and standing a lot, took a few miles but it worked its way loose. Tightened the bolt a smidge to finish the ride and still be able to take the crank off with a rubber mallet.

P!N20

I managed to do that to a DS Tricolour crank by not removing the little magnetic protector cap on my extractor tool. [facepalm]

70sSanO

I forgot to remove the washer removing a Sugino crank and was trying everything, including a hammer on the puller. I didn’t strip the threads, but when finally gave up took the puller out, I noticed the deformed washer and the compressed aluminum. I still have the crank arm but haven’t re-installed it on anything.

Stupid, stupid, stupid.

John

Spaghetti Legs 

”Simple job turned into a disaster”

Story of my life.

To look on the bright side you got to torch something. Similar story, a couple of weeks ago I was removing a rusted in dropout screw. I PB blasted it and felt it give way as I turned the screw but it was really the head twisting off.

Lascauxcaveman 

I've come very close to both these goofs. Each time I was saved by the thought "Waitaminute; I've had this crank off before... there's no way in hell it should be this hard to pull, because I always use fresh grease and I don't crank a crank down all that hard when installing." Don't force it, unless you're truly desperate.

dddd

Assuming here that the OP had the remover fully threaded in to the bottom of the threading, so indication of a well-stuck arm would be unusual torque needed and still not breaking the arm free.

There is an easy way to get such arms off before any damage occurs to the crankarm or to the remover tool:

Leave the puller in place, fully tensioned, then put the cranks horizontal and jump on the pedals hard.
Turn cranks 180-degrees and jump again.
Re-tension the tool, noting if and how far that the tool driver rotates.
Repeat the three steps above until the crankarm comes right off.


If the crankarm threads are stripped:

Remove the bolt and apply LocTite to the inner/outer spindle/bolt threads.
loosely hand-tighten the bolt, then back it off a full turn and half. Allow Loctite to cure (heat greatly accelerates curing).
Apply penetrant to the spindle taper.
Jump on pedals as above, or, that failing, go riding in steep terrain (bring a bolt wrench to monitor progress and to adjust the bolt as needed for ride home).

bear_a_bug 

Oh God, been there, done that. Nearly reduced to frustration-tears as I hammered away on the crank puller. Took about 30 minutes before I gave up, unscrewed the crank puller and saw where I'd gone wrong. Think about it every time I pull a crank now.

Bianchigirll 

I did that an Ofmega crank on a Bianchi Trofeo once. I wasn't really intending to reuse the cranks but still it stunk.

Stein used, or maybe still does, make a tool for this but when I was thinking about one years ago it was pretty spendy. It retaps the threads oversize and then you install their oversize self extractors. One down side I saw, aside from price, is you kind of need to do both arms or atleast use a matching extractor on the undamaged arm.

dedhed

i think i have a blaze crank off my 91 trek

nomadmax 

That's a fellow Jarhead for ya

3alarmer

...i know this is too late already, and I'm not intent on adding to your sorrow, but if you have a propane torch, and it appeared that the crank was stuck on pretty tight, why not do a couple of heating/cooling cycles right at the crank/ spindle interface before applying all that torque ? I've done that a couple of times, and it helps a lot, especially when you use some penetrating oil at the spindle crank joining surfaces. The oil wicks in like magic. Doesn't seem to hurt the crank, and it doesn't get hot enough to damage the case hardening of the spindle.

But anyway, that's for the future. There's a repair you can do using an oversized crank puller and a repair insert from Stein.*

*edit: I see this tool has already been referenced above.

But it's not cheap to buy the tool. I got one to take advantage of all the relatively nice stripped out cranks that were showing up at the co-op here for a while, but it's probably not worth buying one for the occasional disaster.

Thomas15

Would it be possible to use a small 3-jaw puller to remove crank arms if you strip the threads intended for a crank puller?

tyler_fred

So should crank arms be pulled periodically and a light coat of grease be reapplied to the spindle as a preventative measure against such disasters?

sloar 

To answer a couple questions and remarks, I did have the puller threaded all the way in. I really didn't crank any harder than I have before on other cranks without issues. This was all done by hand, Ive had to use a rubber mallet in the past without stripping the threads. It was a total surprise to see the puller just fall out of the crank arm. I tried using a couple pullers that I have, but the Blaze crank spider wasn't even enough for the puller to sit straight with the axel. I was trying my best to save the crank so a torch never came to mind until the threads were toast. Lesson learned on this one.

romperrr 

From my limited knowledge, stuck cranks are a result of over torquing not seized interfaces so I don't think grease would help. Others may disagree and I believe Phil Wood recommends greasing their bb's from what I recall. YMMV

SurferRosa

What lesson, though? Sounds like you did everything right. When we pull cranks, we just do it like we always do it. We never think that an arm is super stuck to a spindle until it doesn't come off. One bad case out of a hundred seems ... tolerable.

A bigger issue is to avoid making it a lot worse (like a trip to the ER) when using a ton of force, a heat gun, and a pickle fork. A lot can go wrong in that environment.

.

Cute Boy Horse

I've only had this happen to me once. I still have the bike and the threads are still stripped. I just remove the arm, cup, bearings and spindle as one unit now. Not losing any sleep over it.

Bianchi84

That's one of those Hatfield/McCoy, east coast/west coast, chunky or smooth arguments!

Andy_K 

I read this thread earlier today, was silently glad it wasn't me, and went about my business. Then tonight I decided to pull the crank on a bike I bought recently to regrease the bottom bracket. I didn't get as far as the crank puller before the suffering began. The drive side dust cap came off very easily as it should. The NDS dust cap on the other hand...



The hex hole was rounded off before I started. I had no luck with a screw extractor. I drilled holes for a pin spanner, which gave me really good leverage, but the cap refused to budge. So I cut a slot to try a flathead screwdriver. Then I hit the edges of the slot with an old dull chisel. Then I used penetrating oil. Back to the pin spanner, I got it to make a quarter turn, but it would go any further. Finally, I got out the heat gun and went back to the pin spanner. Finally, it started to move under near as much force as I could manage. It took about a turn and a half before it started to loosen up.

How in the world do you get a dust cap on that tight?

But it finally came out. The crank came off easily for me. Neither cup shows any signs of being open to moving. The lockring at least came off easily. Now, penetrating oil and sleep. Maybe it will feel like coming out tomorrow.