Giant Boulder Alu Shock Bottom Bracket

Eugbug · 07-16-2012, 05:10 PM

I have a Giant Boulder Alu Shock of late Nineties vintage. I'm not sure whether there are various model types of this bike but I am wondering whether the bottom bracket on this MTB is a single piece unit or whether it can be dismantled and cleaned. It is beginning to make grinding noises so I need to either clean the bearings or replace the cartridge.

Painkiller · 07-16-2012, 05:32 PM

pics would be nice, but it is probably a cartridge style and I recommend you to replace it.make sure you get the correct shell width and spindle length..ie 68x113 or something like that. it may have visible markings you can see once removed. if you bought the bike used I would spec the crank and make sure the correct one was installed in the first place. a good thing to do anyway. people do half ass things once in a while so try to double check to be sure.
You will need a crank puller, bottom bracket removal tool and a little know how

Eugbug · 07-24-2012, 04:00 PM

(07-16-2012, 05:32 PM)painkiller Wrote: pics would be nice, but it is probably a cartridge style and I recommend you to replace it.make sure you get the correct shell width and spindle length..ie 68x113 or something like that. it may have visible markings you can see once removed. if you bought the bike used I would spec the crank and make sure the correct one was installed in the first place. a good thing to do anyway. people do half ass things once in a while so try to double check to be sure.
You will need a crank puller, bottom bracket removal tool and a little know how

Ok, being relatively ignorant about bicycle jargon and parts, I have done some swatting up on the Net.
I don't know whether I have an ISIS or Shimano BB until I can extract it from the shell. It has a square spindle.
The extraction tool needs to have 20 splines but is there any way of establishing which BB I have by measuring the diameter for instance? Will a Shimano tool like this one fit an ISIS BB?:

http://www.wiggle.co.uk/cyclus-bottom-bracket-tool-shimano/

Painkiller · 07-24-2012, 05:12 PM

you do not have an ISIS BB with a square taper spindle. measure the length of your spindle and buy one with that length. if you have not owned the bike from new, I recommend to spec the crankset you have and buy the correct spindle for your crank just in case the one on the bike now is incorrect.

Eugbug · 07-24-2012, 05:21 PM

(07-24-2012, 05:12 PM)painkiller Wrote: you do not have an ISIS BB with a square taper spindle. measure the length of your spindle and buy one with that length. if you have not owned the bike from new, I recommend to spec the crankset you have and buy the correct spindle for your crank just in case the one on the bike now is incorrect.

From what I have read, there are JIS and ISO standard tapered square spindles with different taper angles. Is it possible to identify them by using a calipers to measure the width of the end of the square section?