Crankshaft end tapers.

AMuzi wrote:
On 6/26/2020 10:57 AM, Dan S. MacAbre wrote:
Is it possible that there are more than one kind of taper?
I recently had to replace the bottom bracket bearings on the
missus' Italian bike. I had to get one a little wider (70mm,
I think) and of smaller diameter than most; but I got a
Shimano one that fitted correctly.* But since then, the LH
pedal bolt has tended to slacken slowly, and the crank makes
an embarrassing creaking noise int time with the pedalling
effort oscillating from left to right.* Is it possible that
the Ofmega pedals fitted to it are not fitting the taper
correctly?* No play can be felt by hand, and they are still
almost impossible to remove without lots of unpleasant
hammering with a tapered car balljoint splitter.

Speaking of which, is there a tool that can get pedals off
easily?* I had a tool that screwed into the side of the
pedal, but instead of pulling the pedal off, it just pulled
out all the alloy thread that it was supposed to fit into.
Again, is that because the Ofmega pedals have a different
thread there?

There are two common sections of the standard crank taper and they do
not fit each other:
http://www.yellowjersey.org/photosfr...t/3SPINDLE.JPG

Your Ofmega cranks require the rightmost format. What you bought is
shown center. (also, your original was asymmetric so now either your
chainline is askew or the left crank is vary far outboard or both)

Your Ofmega crank formerly used the most common extractor, 22x1mm which
are cheap and ubiquitous. (the other sizes 23.0 and 23.35mm are obsolete
and wouldn't start in your crank anyway. No one who has those tools
would have lent it to you)* Your current format is 'stripped' in that
the threads are missing. Next time seat the tool fully in the crank arm
on clean threads before attempting removal.

Once you acquire the correct spindle, there's no reason not to install
that damaged arm, just note that future removal may be destructive.* If
there's a competent shop near you a TA oversize extractor may be fitted
but that may be more expensive than a replacement arm (many other brands
interchange, Campagnolo, Sugino Mity, SR Royal, original New Dura Ace
#7400, Sugino 75, Miche, Zeus, etc. Not Shimano current products not
Sugino XD not made in china)

People carp and bitch about mouting cranks on dry tapers or wet but
whichever version of heresy you follow, lubricate your fastener
regardless and torque to 35nm.


I did find some original parts on eBay, but they were quite expensive.
The missus is continually threatening to get a new bike, and I thought
the Shimano crank (especially being sealed) was a more satisfactory
option for the price. She does not get attached to old things like I do.

The original problem was that the crank had been left unmaintained for
decades (ever since she bought it as a girl, really). One day, I tried
to ride it to see if I could work out the cause of a noise she was
complaining about, and felt a lot of movement in the crank. After
taking up the slack, the lock ring was no longer able to be fitted,
since there was not enough thread for it to bite onto. While the cups
were okay, the cones were quite pitted, so I did not think that
replacing the bearings would suffice. Maybe it's possible to fit a ring
'behind' the cup to move it out again?

Anyway, it seems like I will need to do some more precise measuring of
the old crank bits (which I have cleaned and kept for reference).