Alright, torque to spec, and that is ?
300-350 in/lb is popular wisdom. And retorque after 25 miles or so, then leave 'em alone forevermore?
===================================================== Mark Petry 206.618.9642 Beautiful Bainbridge Island, WA mpetry@bainbridgeisland.net ===================================================== The quick and the dead.
- Niki Lauda =====================================================
-----Original Message----- From: classicrendezvous-admin@bikelist.org [mailto:classicrendezvous-admin@bikelist.org]On Behalf Of feldmans Sent: Saturday, November 03, 2001 11:31 AM To: Wornoutguy@aol.com; classicrendezvous@bikelist.org Subject: Re: [CR]Overtightening cranks
Vintage advice, from the 70's weight-weenie phase; to install crankarms with
steel bolts and washers, torque to spec, remove steel hardware and replace
with aluminum.
ER
> I attempted to take a crank off of a friends bike who had used a pet
Gorilla
> to install his crank arms. Lucky he had steel crank bolts because it
took
> my 1/2 inch drive breaker bar and a two foot extension of pipe to get the
> bolts free. I almost rounded one. It had not cracked the crank arms but
> they had gone way to far on the spindle. When I attempted to put them
back
> on at the correct torque they worked. A few weeks later he came to me
with a
> new set of arms. It was just as difficult to take them off the second
time -
> the taper was destroyed even with correct torque they were history. This
is
> not as vintage but on my bikes I use aluminum crank bolts. I tighten with
a
> good sturdy steel bolt and my torque wrench. Then I remove the bolts. I
> use red lock tight on my aluminum bolts (one reason they are in a Ti
spindle)
> and I just snug them in. I have not had to retighten them ever. (they
had
> aluminum crank bolts in the 70s so this is kind of vintage). When chuck
> stated that automotive fasteners are replaced that is due to high torque -
> imagine the torque load on a head bolt compared to a bike crank --
imagine
> how much fun you would have replacing a headgasket (TWICE) and putting in
all
> new bolts because you scrimped on head bolts and used the old ones in your
> car- How many of us replace the wheel studs every time we take a wheel off
of
> our cars. I reuse aluminum fasteners on my bikes and have for years never
> had a failure. I can't imagine a steel crank bolt breaking because of
reuse.
> Sam D.
>
>
> _______________________________________________
>
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