Stripped the thread on my crank trying to get it off....

Once you get it off try the screw the puller through from the back side trick, sometimes if it's just the first few turns of thread that's enough to repair it.

secret_squirrel":1skahicq said:

Once you get it off try the screw the puller through from the back side trick, sometimes if it's just the first few turns of thread that's enough to repair it.

Click to expand...

How is that supposed to work? You've got an effed thread on one side and a square taper hole on the other. Therefore threaded part doesn't go all the way through.



To fattiman,

I have a method that I used to get a NDS crank off. Should work for a DS crank too. Edited quote from my post on the "And today I did" thread on MacRetro.

"It's a Giant Trance X3, 2008 I think, the extractor threads on NDS crank (FSA Alpha Drive) had stripped so crank arm was looking like getting destroyed to remove it to replace knackered splined BB, a Power Drive BB. So when I saw him at the weekend last he asked me what could be done to fix his bike, idiot that I am I said "I'll get it off no bother" :roll: . Tried a method that had worked on an old Shimano crank, a ball joint splitter, wouldn't fit due to BB having spacer for arm to hold against. So tried a bearing puller that locks the pulling arms in place but due to steel puller and aluminium crank the puller was just sliding and scratching crank. Feck.
Then I had a bright idea of somehow bolting/fixing another crank arm that had good extractor threads onto fecked one. Removed pedal then bolted the 2 crank arms together with a spacer between pedal threads so that BB ends of cranks were in line and square to each other. Rummaged in shed and found a 2" diameter exhaust clamp, fitted this with the u-bolt part around the back of stuck crank with a big socket in hollow in the back of crank to prevent damage from the u-bolt, the other part of clamp, the pressed steel bit, just clamped up against the "extractor" crank. Tightened it all up, it wasn't moving. Had to cut down a longer bolt to about 40mm to fit inside the bolt threads on BB so that the extractor could reach being too far out from the BB axle.

So the moment of truth arrived, tightened extractor and the 2 cranks were no longer tight together , did the clamp nuts up tighter but then noticed that the cut down bolt in BB had crumpled with pressure. Replaced it with slightly thicker bolt which didn't bend as much, gave the crank arm a bit of a tap with tool number 1 and off it came. Apart from scratches which are merely cosmetic and a wee dent from big hammer the crank is OK and can go back on with new BB.

For future use I'll find a proper high tensile steel bolt that will thread into BB axle to sort the bending of the bolts made of cheese I had to hand."

If it works this time, it can be used in the future to take off crank so hopefully no need to cut off or otherwise damage crank.

going to have a go later with a rubber mallet and some heat!

New tools arrived ....happy to help if you need it:



All the best,

Re:

Just ride it up and down the street and if will come off, wont destroy the crank

Re:

Have used these very successfully in the past

http://www.arceurotrade.co.uk/Catalogue ... dges---NEW