Re: [CR]cottered cranks question

(Example: Framebuilding:Tubing)

From: "John Swarbrick" <johnswarbrick@hotmail.com>
To: bob.reid1@virgin.net, Classicrendezvous@bikelist.org
Subject: Re: [CR]cottered cranks question
Date: Fri, 09 Feb 2001 13:59:30 -0000


Hi Bob,

I have a cottered crank fitting session coming up soon. I'm using Durax cranks with a Baylis Whiley BB with english cotters My problem is that when I 'dry fit' the axle and cranks together. The cotter pin goes through the 'correct' ammount on the spider side and only needs a bit of filing for a perfect fit. However on the LH crank the pin barely goes through at all, with only a bit of the thread showing at the end. This is going to take lots more filing. I guess the more you file the more chance you have of altering the angle of the 'flat' and therefore the cranks won't be 180' apart.

Is this normal or do I need to get some other cotter pins. swaping the pins I have around makes no differance. I'm guessing the differance lies in the BB axle or crank.

Your right you can 'feel' quite accurately with a spanner. Cheers,

John.


>From: Bob Reid <bob.reid1@virgin.net>
>To: <Classicrendezvous@bikelist.org>
>Subject: Re: [CR]cottered cranks question
>Date: Fri, 09 Feb 2001 13:08:18 +0000
>
>If you get the 'fit' right first the amount of "drawing-on" you have to do
>shouldn't mean running the risk of stripping the threads. I say shouldn't
>-
>but this of course is dependant on just how hard and what's used to tighten
>the nut. I got taught at college, that torque wrenches were just a more
>accurate spanner - spanners then being uniformly of a length that the
>"average" man would tighten it properly and yet not exceed the elastic
>limit
>of the bolt/nut combination when applied correctly (i.e. no bars or tubes
>involved), but this was for "standard" bolts where they were designed for a
>specific clamping load tightened by "standard" spanners - and then there
>were cotter pins, cycle threads and tools (engineering on a budget) and a
>virtual thread war between B.S.A. and Raleigh.
>
>When your faced with a cheap cotterless crank wedged onto the BB axle and
>with no threads left for the extractor to grip on - you might just remember
>how easy most cotter pins were to come out if done correctly.
>
>p.s. I still have not came across "standard-man" (though we do have case
>law
>who says who he is - the man on the Clapham Omnibus)
>
>:-)
>
>best regards
>
>Bob Reid
>Stonehaven
>Scotland
>
>
>
>
>
>
> > From: RALEIGH531@aol.com
> > Date: Fri, 9 Feb 2001 06:58:25 EST
> > To: bob.reid1@virgin.net, Classicrendezvous@bikelist.org
> > Subject: Re: [CR]cottered cranks question
> >
> > I don't see anything wrong with fine tuning the fit with a file, on the
>other
> > hand I thought you weren't supposed to draw the pin tight with the nut
> > because of danger of stripping the threads on the pin and/or nut.
> >
> >
> > Pete Geurds
> > Douglassville, Pa