which torque wrench?

in message , Rob Morley
') wrote:

In article
Simon Brooke wrote:
in message ,
Anthony Jones ') wrote:
snip
3) grease/don't grease the tapers (tried both).

Grease. Definitely.

You're kidding, aren't you?

No. Copper grease, to be precise. Always.

--
(Simon Brooke) http://www.jasmine.org.uk/~simon/

my other car is #Subr-Car: #5d480
;; This joke is not funny in emacs.

in message , Rob Morley
') wrote:

In article
Pete Biggs wrote:
Rob Morley wrote:

I've never seen any debate about it - who says the taper should be
greased?

Jobst Brandt -
http://www.sheldonbrown.com/brandt/i...ng-cranks.html

I've had no problems whatsoever since doing this, although to be fair
the few before (a long time ago) might not have been anything to do
with lack of grease.

I've never had a problem with my own cranks loosening in over 25 years
of using square-taper cotterless cranks. After ten years in the bike
trade I'm only aware of one loosening problem with a crank I fitted -
that had grease on the taper. I've not seen any evidence of crank
bolts
routinely working loose when properly tightened. I've never split a
crank. And I don't use dustcaps on my bikes, because they only trap
water. I wonder why JB has had such a different experience.

Oh, God, cotter pins. How I /loathed/ cotter pins. The square taper crank
has to have been one of the best innovations ever. It seems to me I've
been using them for about thirty years, and, while cotter pins *always*
gave me problems, square tapers have been very, very reliable. I've
never split a crank; I've very, very rarely had a bolt (or, in earlier
times, nut) come loose accidentally; and, as I've said, I've had a grand
total of two cranks come off (both non-drive-side) in those thirty
years. As far as I'm concerned, square taper is something that Just
Works[tm].

--
(Simon Brooke) http://www.jasmine.org.uk/~simon/
;; Let's have a moment of silence for all those Americans who are stuck
;; in traffic on their way to the gym to ride the stationary bicycle.
;; Rep. Earl Blumenauer (Dem, OR)

in message .com, David
Martin ') wrote:

Simon Brooke wrote:

H'mmm... I've three square taper systems still in use. One's 18 years
and about fifteen thousand miles old (cranks; the BB's been replaced
at least twice, probably more times, and the rings have all been
replaced);

Bah! The Ultegra crank that was on my good bike got changed to the
fixie at about 25k miles and the (original) BB was absolutely fine. No
ring changes and no worries..

The expensive stuff lasts (to a point) the cheaper stuff doesn't.

This is a mountain bike. Mountain bikes live in a world of granite dust,
sand, mud and other nasties. The original rings were Biopace (version
2); I'm one of those odd people who liked Biopace very much.

--
(Simon Brooke) http://www.jasmine.org.uk/~simon/

;; in faecibus sapiens rheum propagabit

in message , Anthony
Jones ') wrote:

Simon Brooke wrote:
I don't like to use force when doing things up,
because if you do, how will you undo them?

How would I undo the crank bolt? I'd just ride the bike around for a
bit, and my legs would magically loosen it.

The cranks do (and should) naturally squirm up the taper a bit, so after
a while the bolt will be loose. You should not retighten it, because
that way leads to cracked cranks.

I'd rather have to cut my cranks of with an angle grinder (when the BB
gives up) instead of re-tightening them all the time, but the cranks
evidently don't like that idea.

If it isn't a horribly rude question, what do you weigh? And are you
landing big jumps?

--
(Simon Brooke) http://www.jasmine.org.uk/~simon/
Iraq war: it's time for regime change...
... go now, Tony, while you can still go with dignity.
[update 18 months after this .sig was written: it's still relevant]

Rob Morley wrote on 31/08/2006 17:24 +0100:

I've never seen any debate about it - who says the taper should be
greased?

Its a debate in places like rbt of a ferocity that is on a par with
Campag v Shimano

--
Tony

"Anyone who conducts an argument by appealing to authority is not using
his intelligence; he is just using his memory."
- Leonardo da Vinci

Simon Brooke wrote:
If it isn't a horribly rude question, what do you weigh?

75kg.

And are you
landing big jumps?

Big jumps, no. Yes to small jumps without any suspension however.

Anthony

Simon Brooke wrote:
Oh, God, cotter pins. How I /loathed/ cotter pins. The square taper crank
has to have been one of the best innovations ever. It seems to me I've
been using them for about thirty years, and, while cotter pins *always*
gave me problems, square tapers have been very, very reliable. I've
never split a crank; I've very, very rarely had a bolt (or, in earlier
times, nut) come loose accidentally; and, as I've said, I've had a grand
total of two cranks come off (both non-drive-side) in those thirty
years. As far as I'm concerned, square taper is something that Just
Works[tm].

Maybe if they had usenet 30 years ago lots of people could have told you
that they'd had no problems with cotter-pins.

Anthony

Anthony Jones wrote:
Big jumps, no. Yes to small jumps without any suspension however.

And in the interests of reaching a conclusion here, I should probably
admit to most of the landings being far from graceful...

Anthony

Simon Brooke wrote:

As you know, the crank
tends to squirm up the taper in use anyway, so preloading it
excessively with the bolt is not necessary. And, in my opinion, one
failure every hundred thousand miles ain't broke.

The crank could get damaged if it's too loose to begin with. Cranks can
move back down as well as squirm up. It'll only continue squirming up if
the bolt is repeatedly re-tightened (not normally necessary or advisable).

I'm not suggesting that anyone with no problems for tens of thousands of
miles should tighten anything or refit, but to those people in doubt fitting
cranks now: look up the recommended values and use a torque wrench.

~PB

in message , Anthony
Jones ') wrote:

Anthony Jones wrote:
Big jumps, no. Yes to small jumps without any suspension however.

And in the interests of reaching a conclusion here, I should probably
admit to most of the landings being far from graceful...

The loading on your cranks, if you land even modest jumps ungracefully
(and if like most mountain bikers you habitually do so with the cranks
horizontal) is going to be pretty high. I suggest what you need is
practice landing jumps gracefully.

--
(Simon Brooke) http://www.jasmine.org.uk/~simon/

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