Yet Another Cycling Forum
Random Musings => DIY => Skip Bike and Bodge It => Topic started by: Trull on 12 April, 2013, 12:22:19 am
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About 15 years ago I bought a nice Athena Triple and fitted it to my Randonneur using SPD M-520 pedals to turn it, well the pedals are definitely killed now and it has taken me 3 months of on/off attention to get them off without harming the cranks. The winning formula was to apply heat with a butane gas torch then a goodly spray of Halfords Shock and Unlock penetrating oil (I think its actually isopropyl alcohol, it boils off really quickly) and a little spray of WD-40 then wait some time before repeating after standing on a suitably sturdy pedal wrench. I'm 16stone - which helps btw.
So, happy day - I managed to get both pedals off and the lithium teflon grease had turned to chalk dust and now I'm pedal shopping :-)
Also the penetrating oil is really good at cleaning oily/greasy stuff -and evaporates off without any residue.
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probably wise to run a tap through to clean up the threads before fitting the new pedals. :)
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Very good idea!
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You missed out the scaffold bar on the park pedal spanner stage before resorting to the blowtorch...
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Yeah I did try using a 1.8m handy bit of 75x20 ally box section, but backed off as I was scared of stripping the threads. The application of heat using a MAPP type gas blow torch was the best - and kept the temperature high enough to slacken but below the critical temp of aluminium. I think I'd recommend people try the thoughtful application of heat before the scaffold pole - also there's a problem with applying a moment like that - you are also generating a massive shear force which adds to the friction and further stresses the threads. You really want to balance the torque by cutting a hole in the pole in the middle, putting the wrench in the pole and then turning it by push/pulling the far ends to balance the forces to get pure torque in the middle.
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A trick I was told with any tight bolt (pedal) is to try and tighten it just a bit more to break the bond then undo it!