John
I don't accept that reasoning. Because the left side isn't under stess due to it being on the 'rise' when the load is on the right side. All complete machines sold in th UK when cotters were current had them with the heads leading. 'If it ain't broke...don't fix it!'
Derek Athey Honiton, Devon UK
On Sat, May 15, 2010 at 12:55 AM, John Betmanis <johnb@oxford.net> wrote:
> On 14/05/2010 5:30 PM, Derek Athey wrote:
>
> The 'head' of the cotter always 'leads' the stoke, thereby giving the
>> strongest point of energy on the down stroke using the strongest point
>> of the cotter against the flat of the axle to reduce stress.
>> That way one also ensures that the cranks align perfectly.
>>
>
> Derek, that does make sense, although they would be perfectly aligned
> either way, provided both sides are the same direction. However, I just did
> an image search and still see it both ways. In fact, one image was on
> Sheldon Brown's site, where he says this:
>
> "Some older books speak of installing the cotter so that the pedaling load
> is taken by the thick end of the cotter. This is an error, because if you do
> the right side that way, the left side will be stressing the thin end, and
> vice versa. It really doesn't matter which way you put them in, as long as
> they face in opposite directions."
>
> His reasoning is correct, because it's only the *left* crank that transfers
> load to the BB axle, then the axle transfers it to the right crank and
> chainwheel, through the *thinner* end of the cotter pin.
>
> --
> John Betmanis
> Woodstock, Ontario
> Canada