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Not sure if my bottom bracket needs work or not
Hi Guys,

Im relatively new to biking, havent really biked much since I was a kid but it is something Ive bee wanting to et into so I finally bought a half decent bike (Norco Mountaineer), bought it used as my budget is pretty tight and it needs a little work and as I cant really afford to take it to a bike shop I need to learn to do this all myself.

The crank/axle assembly seems a little loose, Ive tried tightening the crank bolts but it still seems to wiggle a little bit, here is a video I took, if the video doesnt help I can try taking another one.


If this isnt right and I need to do some work on it then please let me know what I need to do/buy to make it right.

Thanks guys!
Hi Dave;

If your BB has loose ball bearings, just take it apart, clean in up, inspect for wear, and put it back together.

You should replace the balls for sure, possibly the axle and cups.

From your video, I can not tell which kind of tool you'll need to remove the bottom bracket. We need an end on view from the left side (non-chain) to be able to tell. My three bikes all require different tools.

First you need a crank puller. Something like this:

The BB construction starting with the left side (far side in the link below), generally (not always!) consists of a lock ring, which needs to be removed first. In the picture in the link below, the tool needed is a 35mm spanner with two tangs 180° apart. Next a pin spanner is needed to remove the bearing cup on the left side. At this point, you can remove the axle, ball bearings, plastic tube between the bearings (keeps dirt from the inside of the frame out of the grease), the rest of the ball bearings. To remove the drive side cup, you'll need some sort of wrench. A 15" adjustable from Harbor Freight is cheaper than one fix bicycle specific wrench, and useful for many other jobs.

You may need to replace your BB axle; like one of these - BUT they come in different sizes.

Alternatively; you can get a sealed BB cartridge, like this one:

On my current project, I am staying with balls, but no retainers, increasing the ball count to provide the strongest, stiffest BB possible. There is room for 14 balls on each side without the retainer, versus 9 on each side with.

Sealed BB require little or no maintenance, but are no stiffer or stronger than ball & cone. The generally run a little smoother (less drag) because the bearings, axle and shell are precision aligned on a machine.
Thanks for the reply nfmisso,

Here's a photo of the crank, youll have to pardon the dirt as I havent gotten to cleaning it yet, want to get it all fixed up first.

It seems like getting a new sealed cartridge might be my best option, how would I go about figuring out what size I need? Also are there any other sites that have em for a good price? Im from Canada and amazon has this thing against shipping most things here.

Thanks again, I a really appreciate the help, and Im a little relieved that this will be a little less expensive of a fix then I thought it would be
The lock ring comes off with the spanner, looks just like the one in the link.

The cup comes off with some sort of tool, really need a picture from a slightly different angle to suggest which one.
Which angle would be best? I think this bike has a cartridge BB, at least thats what the newer mountaineers have and I dont think this one is that old.

Also, is the crank puller really a necessity? the crank will just pull off with the proper application of foce wont they?
you have a conventional BB set, not a sealed unit.
The parts look like this, the left cup , on the left in the pic, has a lh thread, and fits behind the rh crank. Look down behind the chainwheel to see if the face of the cup is tight against the BB shell, if not and you can see a gap or any movement here, you will need to do a complete dismantle.
The rh cup, shown here with an hex instead of peg holes as yours has, is rh threaded and all adjustment is carried out here.
It may be, just to keep you rolling, you can tighten this cup a little to get rid of the shake in the crank.
Back off the lockring, should use a peg spanner, but a blunt punch and a hammer will do just as well. Now using the same punch, lightly tap clockwise in the holes in the inner cup, hopefully moving it in enough to eliminate the shake, retighten the lockring. You should be able to do this without removing the crank arm.
Now assess the assembly, does it move freely without drag and without shake, if so, job done, if not you will need to repeat or do a complete dismantle using a crank puller to take off both crank arms.
(04-20-2011, 12:33 AM)Dave3 Wrote:  ..<snip>...

Also, is the crank puller really a necessity? the crank will just pull off with the proper application of foce wont they?
A crank puller is required.

You can get away without using one IF and only IF you are trashing the cranks and BB axle, and probably the bearings and bearing cups.
I do not know where you are, BUT after taking my BB off I could not find replacement parts (which is pretty typical nower days) no one fixes stuff anymore.

I got a Shimano UN54 sealed BB installed for $50 total.($25 part $25 labor) Thats a good deal, the bracket is excellent and special tools and experience is needed to install it. It saved me money having it done, and dealer installed has warranty. But than I get several dealers within a few blocks here in S Cal.
Never Give Up!!!

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