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Old 04-07-11, 01:22 PM   #1
Amesja
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Cotters -to lube or not to lube

I've always installed cotters with lube on everything but leaving the load bearing cut and the notch dry. I also always lubed the spindle and the crank arm too.

Now I'm reading Barnett's and he says to do it dry.

Have I been doing it wrong all along? Or is this like the grease/no-grease wars on square-taper cranks? (I grease those too)
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Old 04-07-11, 01:58 PM   #2
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Torque specifications are typically for dry parts (not lubed). There should be significantly less torque used when lubrication is inlcluded, as much as 40% of dry torque spec. Specifications take into acount the assembly and the fact the part are dry. Why would you lube the parts? Are you preventing rust or other corrosion concerns? There is a possibilty of over torquing if you use lube unless you know the proper torque spec to use for the lubricant used.
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Old 04-07-11, 02:37 PM   #3
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Quote:
Originally Posted by SJX426 View Post
Torque specifications are typically for dry parts (not lubed). There should be significantly less torque used when lubrication is inlcluded, as much as 40% of dry torque spec. Specifications take into acount the assembly and the fact the part are dry. Why would you lube the parts? Are you preventing rust or other corrosion concerns? There is a possibilty of over torquing if you use lube unless you know the proper torque spec to use for the lubricant used.
Cotters aren't torqued, they are press-fit. You can't get them too tight. I understand how torque values are modified from dry threading to "wet." This is different. There is no torque involved. The press specification is "at least 50lbs of pressure" according to Barnett's.

The idea behind lubrication is that they don't creek and squeek.
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Old 04-07-11, 03:38 PM   #4
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It ok to lube for reasons such as preventing rust or other corrosion concerns. I have done it for years and never have a problem.
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Old 04-07-11, 03:58 PM   #5
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Cotters themselves are intentionally a soft steel, the nut is just there to keep it in place .

so very little torque on the nut.
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