Bicycle Mechanics - Cottered Cranks to Sugino RD

Hi,

I have cotttered crank on a converted fixie and can't stand how much they loosen due to the torque. So i'm going to switch over to Sugino RD cranks...I'm just making sure I'm doing this right. If you can let me know if my logic is correct and if i am missing anything i would appreciate it..sorry that i am kinda clueless about this

First, take out cotter pins and get rid of cottered cranks
Second, Get new bottom bracket compatable with Sugino RD cranks (I think i need a new bb to be compatible with this type of crank system, right?)
Third, Install bb and cranks
Fourth, Go ride

Thanks

You do have it right.

Although, many people with a lot of torque have rode many miles on cottered cranks without them loosening.

The right size cotter, and installing with a cotter press will do the job.

You do get some weight savings going cotterless, but to me the cottered look would go good with a fixie.

Hi,

I have cotttered crank on a converted fixie and can't stand how much they loosen due to the torque. So i'm going to switch over to Sugino RD cranks...I'm just making sure I'm doing this right. If you can let me know if my logic is correct and if i am missing anything i would appreciate it..sorry that i am kinda clueless about this

First, take out cotter pins and get rid of cottered cranks
Second, Get new bottom bracket compatable with Sugino RD cranks (I think i need a new bb to be compatible with this type of crank system, right?)
Third, Install bb and cranks
Fourth, Go rideThis may be as easy as that, but odds are it won't. Can't tell since you neglected to mention what kind of frame you're dealing with.

If it's an English frame made by Raleigh in Nottingham, or if it's French or Swiss, you could be opening a big can of worms.

If it's an Asian-built frame, or an English frame built outside of Nottingham, it will be as easy as you mention.

See also: http://sheldonbrown.com/bottombrackets

Sheldon "Not So Fast..." Brown

This may be as easy as that, but odds are it won't. Can't tell since you neglected to mention what kind of frame you're dealing with.

If it's an English frame made by Raleigh in Nottingham, or if it's French or Swiss, you could be opening a big can of worms.

If it's an Asian-built frame, or an English frame built outside of Nottingham, it will be as easy as you mention.

See also: http://sheldonbrown.com/bottombrackets

Sheldon "Not So Fast..." Brown

I ran into this problem about 20 years ago trying to replace the "Stronglight" cottered crank on a friend's early 70's Nottingham Raleigh with a square taper SR crank. I removed the original crank and adjustable cup and then discovered Raleigh proprietary bb threading.

What I wound up doing was using the SR bb spindle installed in the Raleigh's original cups. It worked out ok and the bike is still in service. If we ever destroy one of the cups, we are going to have a real problem.

its is english threading so it sounds like im ok

on another note, what is the best way to get cotter pins out without a cotterpress...i really want to do this crank conversion myself but dont want to buy a 50 dollar cotter press. Thanks!

Since it sounds like you don't care about the cotters anymore, just tap/pound them out with a hammer. Make sure to support the bottom side of the crank arm so you don't apply torque to the BB shell.

Agreed. Even though you are having trouble with the cranks loosening, so it shouldn't be the case, they are sometimes stubborn.

For this (and many other cycling related issues) search sheldonbrown.com for ideas and thoughts.

...what is the best way to get cotter pins out without a cotterpress...i really want to do this crank conversion myself but dont want to buy a 50 dollar cotter press.!
Wow, you've found a cotter press for only fifty bucks! ;-)

You need an IIAI. See: http://sheldonbrown.com/cotters for instructions.

Sheldon "Inerrtial Impact Alignment Instrument" Brown