replacing cranks

Okay, I finally removed the old cranks by using a nifty tool called CWP-5.
Now I have a question about putting on the new cranks: What are the best
methods of doing it?

Do I add my hand pressure to push down the crank over the tapered square
bolt, then tighten down with a bolt nut? Or should I use a rubber mallet to
hit the crank so it can go down further, then tighten down with a bolt nut?

there have been many a thread on this very topic. I cant remeber what the last one was called, but do some searching and you should be able to find it.

Re: replacing cranks

I just found this web site that answered some of my questioins.

What I don’t understand is why use grease??? I thought grease should only
apply to moving parts, and there
doesn’t seem to be any moving parts.

a. Wipe both sides of spindle and inside crankarm mounting holes with a rag.

b. Grease under head and threads of both bolts (or nuts in some models).

c. Install right crankarm onto right side of spindle.

d. Thread crankarm bolt (or nut in some models) into spindle.

e. Tighten crankarm bolt to manufacturer’s recommended torque.

f. Grease threads of dust cap (if any) and install snug.

g. Install left crankarm onto left side of spindle with arm pointing
opposite direction of right side arm.

h. Install crankarm bolt or nut and tighten.

i. Grease threads of dust cap (if any) and install snug.

I just finished up this, and was about to post it…I’ll give you a sneak peek:

dont use bicycle sites as a referance for unicycle crank installation,if you tighten just the nut you will strip the threads.

use grease so the arm goes on farther and so you can get it off someday.

use your rubber mallet then tighten the bolt.then go ride for awile and hammer away on the crank again and tighten the nut again.check your nuts regularly (crank nuts that is :roll_eyes: ) they do loosen a bit with time.

wheres the pic of the mallet in use?

If you need a pic of hammering a bar…

Oh, I like Sofa’s little instruction page. Only thing I would add for the crank install is to make sure you don’t get any grease where the retaining nut will sit or on the threads for the retaining nut. Grease there will keep the Loctite from getting a good bond which can allow the retaining nut to loosen on its own.

Grease the tapers
Press (or pound) the crank on
Make sure no grease gets on the threads for the retaining nut
Put Loctite on the retaining nut
Tighten the retaining nut

Re: Re: replacing cranks

Along with all the other great advice, I’d have to add that there are indeed moving parts. I would consider the action of the crank moving along the surface of the taper as it’s installed a moving part.


Re: Re: replacing cranks

As well as moving parts, you want to put grease where two metal surfaces come in contact. This prevents them from seizing together (like the seat tube in the frame) and in the csaee of cranks, it also lets the cranks slide up the spindle easier

Re: Re: replacing cranks

Scott Bridgman has an article on <> about why grease on the tapers is a good thing.

<> Click on “Crank Installation” on the left side of the window.

The article is from one of the rec.bicycle* FAQs.

Didn’t Ewan start a repair and maintenance FAQ recently? Doesn’t it have this recipe for crank installation? Where is it?