Can non cross threaded pedals sieze to the point they rip the aluminum threads out?
#1
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Can non cross threaded pedals sieze to the point they rip the aluminum threads out?
I just put a fair amount of effort (no additional leverage, just a 10" wrench) to remove pedals off a bike teetering on being too rusty to bother with, and on both sides the pedal threads took a fair amount of aluminum with them (cranks are Sugino VPs).
Now I'm wondering whether I'm at fault for being too gung-ho about getting these pedals off before soaking them in ammonia or something (they never gave after the initial movement), or whether they were cross threaded to begin with. I've put waaaay more force into removing pedals before (me with a 6 foot pipe), and all that resulted in was a warm pedal.
Have you seen a properly threaded pedals so seized it took some aluminum with it?
As a side question, how much should I expect to get charged to have the cranks re-tapped? (I can thread pedals on, but not sure whether I feel good about it) Or should I just buy a set of Park TAP-6 taps for about $35 so I can be prepared and then this will never happen again
Now I'm wondering whether I'm at fault for being too gung-ho about getting these pedals off before soaking them in ammonia or something (they never gave after the initial movement), or whether they were cross threaded to begin with. I've put waaaay more force into removing pedals before (me with a 6 foot pipe), and all that resulted in was a warm pedal.
Have you seen a properly threaded pedals so seized it took some aluminum with it?
As a side question, how much should I expect to get charged to have the cranks re-tapped? (I can thread pedals on, but not sure whether I feel good about it) Or should I just buy a set of Park TAP-6 taps for about $35 so I can be prepared and then this will never happen again
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That does not look good. Remember that the pedal shafts bear your entire drive force, and there is a natural torque moment which tries to rip them out of the cranks. If you promise never to stand/"dance" on the pedals, you can cautiously use those cranks awhile longer.
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Capo: 1959 Modell Campagnolo, S/N 40324; 1960 Sieger (2), S/N 42624, 42597
Carlton: 1962 Franco Suisse, S/N K7911
Peugeot: 1970 UO-8, S/N 0010468
Bianchi: 1982 Campione d'Italia, S/N 1.M9914
Schwinn: 1988 Project KOM-10, S/N F804069
"Far and away the best prize that life offers is the chance to work hard at work worth doing." --Theodore Roosevelt
Capo: 1959 Modell Campagnolo, S/N 40324; 1960 Sieger (2), S/N 42624, 42597
Carlton: 1962 Franco Suisse, S/N K7911
Peugeot: 1970 UO-8, S/N 0010468
Bianchi: 1982 Campione d'Italia, S/N 1.M9914
Schwinn: 1988 Project KOM-10, S/N F804069
#4
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You could get a heli-coil put in for 1/2" pedals, but that limits your pedal selection, and might be more time and hassle than it's worth unless you have machinist friends.
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My recommendation: toss it all out. There's nothing worth saving.
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#7
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Don't blame yourself, those were hopeless before you got to them.
Heli-coils and a wire-brush mounted on a grinder for the pedals if it's worth it to you - or just toss the lot.
And - I know you know this but some newbies may not - this is one reason why you always GREASE the threads.
Heli-coils and a wire-brush mounted on a grinder for the pedals if it's worth it to you - or just toss the lot.
And - I know you know this but some newbies may not - this is one reason why you always GREASE the threads.
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It's called galvanic corrosion. When you put two dissimilar metals in contact they begin to corrode. They will eventually become basically welded together if you haven't taken precautions to prevent the corrosion. And when you try to remove the part, it just rips the threads right out. Pedal threads and spoke nipples always tend to be problem areas and should always get a dab of anti-seize compound.
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Bummer. Didn't know it could get that bad.
It was a $5 Centurion Accordo, mid-80s sea green/gray two tone model. If there are any more surprises like this, it may just never see the road as a complete bike again.
It was a $5 Centurion Accordo, mid-80s sea green/gray two tone model. If there are any more surprises like this, it may just never see the road as a complete bike again.
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Yup. I haven't had that specific (pedal to crank) problem, but on my folding bike, which is mostly aluminum, I've had several stainless steel fittings get so comfortably mated to aluminum that the same thing happened. Stainless... but not corrosion-proof. As said above, always grease the threads. And when you buy a new bike, take every every everything apart, and grease it all, and put it back together. Yes, that's a PITA, but the alternative (galvanic corrosion) is at least an equal PITA, fnot worse.
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It's not the first time I've seen pedals do that to a crank - all because someone ran them in dry.
If you want to save the pedals, the best way is to get right and left handed 9/16 dies and run them back over the threads.
If you want to save the pedals, the best way is to get right and left handed 9/16 dies and run them back over the threads.
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