I've admitted defeat...........

[Reluctant]

Bi-metallic corrosion is nasty stuff.
Heat the crankarm may help.
Overnight in PlusGas might help.
Saturated solution of caustic soda and immerse overnight might do it. It works with seized seatposts. Just need to be careful with skin contact and wash completely after.
But some things are just plain stuck and you may find that the steel thread just tears the aluminium apart when it does move.
Good luck!

 

[Anthony]

Saturated solution of caustic soda and immerse overnight might do it. It works with seized seatposts. Just need to be careful with skin contact and wash completely after.

I think this attacks aluminium, so it might release the pedal, but won't it destroy the crank arm in the process?

 

[SeeingisBelievingGTMuseum]

2-4' pipe over the end of a standard 15mm open end wrench will do it...as long as your turning towards the rear of the bike....it's all about leverage.

 

[EarlofBarnet]

Perservere (sp?)!

I've spend a good few hours this weekend sawing a crank arm off a bottom bracket. Definitely a big sigh of relief when you finally suceed

 

[any123]

drill it out thats what i did

thanks andy

 

[bigyinn]

You'll be lucky to get a drill to touch the axle material.
Had a similar problem. Ended up taking the pedal body off the axle, removing the pedal bearings, leaving just the axle.
Then ground two large flats on the axle with a bench grinder, locked the so and so in the vice and swang on it with all my weight, BINGO.

 

[the great roberto]

There was a real risk of me doing damage to myself. Tried drilling it out.No luck.Even my grinder had to work hard cutting the dam pedal off.

I did finally admit defeat and they went to the tip. The 42T ring was worn (but I've got a spare and teh arms were nice.


RIP M739 Cranks.

 

[poolio]

Been intending to 'upgrade' the toe clip pedals (to SPDs) on my 92 Orange... not sure they've ever been removed in 19 years, managed to knacker an adjustable and a spanner already - and a nice chunk of ankle... been trawling the net... and it seems that some form of penetrating goop (for a week or so) a fair blast of heat and some brute force will do the trick... anyone got any other tips?

 

[ishaw]

There was a real risk of me doing damage to myself. Tried drilling it out.No luck.Even my grinder had to work hard cutting the dam pedal off.

I did finally admit defeat and they went to the tip. The 42T ring was worn (but I've got a spare and teh arms were nice.


RIP M739 Cranks.

Patience and soaking is key, as is a lot of leverage. Sorry to hear that you admitted defeat, but if you now have a spare ring........

 

[poolio]

In the end took the bike to Woodsons Cyclelife in Edgeley Stockport... and the owner (John?) whipped out his massive spanner and teased them both out.. back and forth.. gently gently... didn't lose much thread and now have the SPDs (heavily greased!) installed - good times!