frankstoneline

I have an older (78 or 79 i think) pinnacle fs12 I have been working on that I got from a thrift store for 5 dollars. I tried searching for the answer to my question but my search isnt working and all I get is a blank page so forgive me if this has been answered but i didnt see anything when i looked through the first couple pages in this section. My question is how do I go about removing and replacing the bottom bracket so as to be rid of the foul cottered crank business it currently has attached. I would offer pictures but the bike is currently at my parents house, so any advice would be great. I ask because when I took it apart recently the bottom bracket seemed barren of anything that would lend itself to being removed. Sorry for my search not working, but thanks for any help.

San Rensho 

The hardest part of a cottered crank is getting the cotters out. If you already got the cotters out, the rest is a piece of cake. Just remove the lockring on the non-drive side and remove the movable cup, then take out the spindle. The fixed cup is more of a problem since it is in there really tight and requires a special tool. Be sure you know what type you have as most fixed cups are left hand threaded but some are right hand. Sheldon has a good write up on how to identify and remove fixed cups. Be aware that conversion to a non cottered BB requires fitting the correct spindle legnth that will give you the correct chain-line.

If you haven't removed the cotters, I would just leave it. Pour about an ounce of oil down the seat tube about once a year to lubricate the bearings and you will be fine.

Sheldon Brown

Right. See: https://sheldonbrown.com/cotters

Sheldon "Inertial Impact Alignment Instrument" Brown

frankstoneline

I would leave the cottered cranks on, and I do have the cotters out (I am fairly positive the "cotters" are the pins that hold the crank arms on, though I might be way off) but the bike is en route to a fixed conversion and the cranks appear to be slightly warped. If I buy a crankset and a bottom bracket to fit it will it create the correct chain line, or do I have to look around for something specific because i'm converting?

San Rensho 

Its the spindle (axle) legnth of the bottom bracket that determines chainline. Every compatible crank/BB combination will have a selection of spindle legnths, e.g. 110, 113mm, etc. You need to determine the right legnth to determine the right chainline.

frankstoneline

So, if I'm understanding correctly. Supposing I buy a bb and a crank from the same place that are compatible, I'm good? I just need to keep in mind the chainline I need, as well as the threading?
Also, when I put the new bottom bracket in, if I get a cartridge style one (I've heard they are easier to maintain in foul weather areas) is there some special way to put it in, like a tool of some sort I need? Also will I need to keep the lock ring from the drive side or any of the other components if I plan to replace the BB with a sealed cartridge style one?