I recently read an article in (I think it was) MBUK, which showed the crankshaft being liberally coated with grease before being pushed through the bearing cups. Surely, the crank relies on frictional contact with the inner bearing race, so what is the point of the grease?
to stop any interaction between the surfaces which may cause them to fuse together. It's literally a slip coat rather than a lubrication
Thanks, Taff. That I can understand, but the pic in the mag showed it oozing grease!
It also protects from corrosion. I grease steerer tubes for the same reason.
Thanks, shedfull. Again, no problem with light lubrication.
TBH all that grease will be stripped off anyhow when you push the axle in?
It will and push up against the drive side bearing seal filling with dirt and grit.
I prefer to lightly grease the plastic bearing seals so the shaft pushed it to the non-drive side where you want some anyway on the splines.
TBH all that grease will be stripped off anyhow when you push the axle in?
It will but the axle will have less of a chance of damaging the lip of the seal on assembly even though it's a small risk anyway
Standard/good practice to grease/oil the lip of most seals before assembly
Dry insertions are never good 🙂
I always grease them, a bit of copper grease and some standard water proof stuff. I have never had one fail and have run about 10 different cranks of that sort over the years. I'm a pretty heavy rider too. Also when I come to take them off they drop out easy. I would never think about assembling one dry! bad practice as said above.
Uplink - you mistook what I was saying - I agree with a bit of grease - it's just the liberal grease will get wiped off (bit of a waste of grease ) 🙂
i.e.
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Why does the crank end have a hole in near the thread? I was looking at this the other day on mine
Is that the hole in the splined section?
It's for the wee shim to fit into - the one that's between the two bolts on the NDS crank.
Yeah the hole near the end of the splined section of shaft you can see in the pic above I'm not getting that though druidth?
There's a small steel plate that the two bolts go through, that has a projection to locate in that hole.
It means the crank won't slide off the shaft if the bolts come loose.
http://www.pinkbike.com/news/technical-tuesday-shimano-crank-installation-2010.html
2m52s in....
He calls it the "Stopper Plate"