Not that I am a great fan of them, but cotter pins are not as bad as they seem. Left to corrode for decades they can be a pig to remove but if the correct sizes are used they are fine. As for specialist tools..... Well I guess that clever little presses exist but usually a smack with a hammer, with a bit of wood inbetween, works well.
As an ignorant youth I found that the back of a wood splitting maul does the job just fine if they are a touch sticky.
Square Taper Cranks
Re: Square Taper Cranks
We don't really know what he is doing?
The picture on previous page shows a lever (socket) attached to a "chainwheel" to drive a freewheel. Is anything attached to the other end of the BB axle?
Cotter pins transfer the drive from the left crank to the (right) chainwheel....you can bludgeon them out on a bicycle, but I don't know where they will be on this device?
If it is just driving the attached chainwheel, then a BB bearing unit is "overkill" ....and if its difficult to work on why do it? square taper and external BBs you can at least dismantle them without resorting to violence. You can't get self-extracting cotter pins any more!
IMG_5141 by 531colin, on Flickr
The picture on previous page shows a lever (socket) attached to a "chainwheel" to drive a freewheel. Is anything attached to the other end of the BB axle?
Cotter pins transfer the drive from the left crank to the (right) chainwheel....you can bludgeon them out on a bicycle, but I don't know where they will be on this device?
If it is just driving the attached chainwheel, then a BB bearing unit is "overkill" ....and if its difficult to work on why do it? square taper and external BBs you can at least dismantle them without resorting to violence. You can't get self-extracting cotter pins any more!
IMG_5141 by 531colin, on Flickr
Bike fitting D.I.Y. .....http://wheel-easy.org.uk/wp-content/uploads/bike-set-up-2017a.pdf
Tracks in the Dales etc...http://www.flickr.com/photos/52358536@N06/collections/
Tracks in the Dales etc...http://www.flickr.com/photos/52358536@N06/collections/
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Re: Square Taper Cranks
I find cotter pins come out ok if fitted with anti-seize. However, the usual scenario is trying to remove pins fitted dry by a bike factory 50 years ago, and left to rust in a shed. If you're lucky, you can get one side off and then you only need a BB and *one* new crank to fix the bike.
A cotter press, a bit like a really heavy-duty G-clamp, is the ideal tool but they are rare and/or expensive.
A cotter press, a bit like a really heavy-duty G-clamp, is the ideal tool but they are rare and/or expensive.