Square taper, grease or not!!!!

Thumb it in.

Skeelsie":6cu1rdhl said:

Thumb it in.

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Oooooo errrrr missus

i've always used a smidge of LM grease, but i may have forgotten a couple of times and i never noticed a difference.

In quite a few years of professional mechanicking, I've never had a problem removing cranks from square taper axles as long as I've had the right tool and good purchase - if the crank threads are stripped, that's another matter. I think this means that the risk of the cranks seizing onto the axle is very small - the interference fit means that they're designed to bind together and the shape will be relatively easy to pull apart even if some corrosion has taken place. It's not quite the same as a parallel fit, like a seatpost in a tube, where seizing will hamper removal; the act of removing square taper cranks will break apart any galvanic corrosion.

Because of this, I've never greased square tapers. The main argument against greasing them is that it makes it easier for the ham-fisted to over-tighten the crank bolts. This will push the crank onto the axle to such a degree that the taper starts forcing the crank apart with more force than it was designed to handle. Cracked split cranks are not much further down that road.

If we're talking the actual taper itself, that the crank arms bolt down onto, then no.

Fitting instructions of my most recent bb's have said no..
I've stripped bikes that have never had the cranks off in 20 years and even without grease there's been no metal binding..

If you really want to use something, a quick wipe over, with some release fluid (loctite 700, 770, etc.) would probably be ok...

I've always used Coppaslip on the tapers and threadlock on the bolts...

...never had a corroded spindle or stuck/loose crank

GT-Steve":wrl036mx said:

If we're talking the actual taper itself, that the crank arms bolt down onto, then no.

Fitting instructions of my most recent bb's have said no..
I've stripped bikes that have never had the cranks off in 20 years and even without grease there's been no metal binding..

If you really want to use something, a quick wipe over, with some release fluid (loctite 700, 770, etc.) would probably be ok...

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If it is a Race face crank then yes you use an anti seize of some sort, says so in their instructions and their cranks are machined with that extra layer in mind.

Just pop in the archive and have a read.
http://www.retrobike.co.uk/gallery2/v/M ... e/Manuals/

RaceFace":wrl036mx said:

NOTE: WE RECOMMEND APPLYING A FILM OF
WATERPROOF GREASE TO THE BB SPINDLE
FLATS BEFORE INSTALLING RACE FACE CRANKS
TO HELP PREVENT CORROSION THAT CAN
OCCUR BETWEEN THE CRANK TAPERS AND THE
BB SPINDLE.
natural movement between the two parts and can
adversely affect the life of the crank arm. While this is
a controversial area , our extensive lab testing has
proven that greasing the spindle flats does not
adversely affect the crank arms, while preventing
corrosion has definite benefits. Cranks tend to "suckon" to a greased spindle approximately 0.5mm
(0.020") further than they would onto a dry spindle
using the same torque value (28 ft/lbs. max.) on the
crank bolt. We have taken this into cons ideration in
the CNC machining of our tapers to ensure it is not a
problem.
Lubricating the spindle flats is especially important
when using a non-plated steel BB spindle (Shimano
UN52) or a Titanium BB spindle, as corrosion attack
is much worse in these cases.

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Square taper and grease? no no no no no no no no NO!

I clean both the crank holes and axle with WD40. Torque up. Ride a bit. Torque up. Leave it alone.

Never had a problem, no apparent damage to tapers, and easy to remove when the time comes.

Jon Smith":2sqsww72 said:

Adding lubrication allows the crank to be pushed on too far damaging the crank tapers, then it is easier for the crank to work loose and become un-usable.

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So lubrication makes it easy to compress steel?