PA28Scuderia

Alright everyone, I have a 2005 Hardrock Sport and after making some observations and plenty of searching on here, I think I need to do something about my bottom bracket. Its been making noise for a while now and it is getting worse. I don't really know much about buying/installing a bb so I wasnt sure if what I found on pricepoint would fit properly. They are showing a Shimano XT UN73 for only $19.98 and from what i read from Specialized and the product info for the new bb, it looks correct. They are both 'square taper' and 68x113mm. If anyone knows if this will work correctly or if you have any suggestions, I'd really appreciate it. Thanks in advance for any and all responses!!

never

It's the right one.

PA28Scuderia

Thanks....Would you know off hand exactly what tools i need to get the cranks off and to replace the bb? Some of the ones that people are recommending in other threads are for the ISIS or whatever that is. If it isnt too much of a hassle, I'd like to try and do this myself.

Blazinall91

you'd better hope and pray whoever assembled your bike greased the threads of your existing BB cups, cause when i switched mine to a Race Face Evolve DH ISIS the existeing drive side cup was seazed and broke two of my LBS's ratchets.

I'd go ISIS it's splined and definately a better product than a square shaft BB

never

It's pretty easy...you'll just need these specialty tools (they aren't expensive) and it helps to have some basic tools like sockets, wrenches, lube/grease, etc...

For pulling the crank arms you can use:

https://www.parktool.com/products/det...=26&item=CCP-2

or this one can do both ISIS/Octalink and your square taper
https://www.parktool.com/products/det...=26&item=CWP-6

For removing the bottom bracket, use:
https://www.parktool.com/products/det...=25&item=BBT-2

You can get brands other than Park but those are what I have.

Blazinall91

you'll need a puller to get your crank arms off and a BB tool which is to some extent a funny looking socket. Figure out how many teeth your existing BB cups are and how many teeth your new one is, the instructions that come with the BB ashould say the tool you need, but you'll have to figure it out for the original BB

never

There's nothing wrong with a square taper setup. I wouldn't say it's worth buying a whole new crankset just to go to an ISIS bottom bracket.

PA28Scuderia

I appreciate the input, i was kind of thinking about changing the whole setup, but ill have to look into that somemore. Those links were helpful, thank you guys.

never

Here are links to the installation procedures...

Crank Arms:
https://parktool.com/repair/readhowto.asp?id=103

Bottom Bracket:
https://parktool.com/repair/readhowto.asp?id=94

Blazinall91

i hated my square shafted BB, it was awful it might as well have been round

never

As long as the arms are installed properly, you shouldn't really have any issues with a square taper BB. Did your arms loosen off and round off the spindle?

PA28Scuderia

I don't believe the arms have loosened themselves, as far as I can tell they are still tight. I'm thinking about picking up the tools later this week and taking a look at everything this weekend to see what I'm dealing with. My priority it to get rid of this aweful creaking noise which I'm almost 99% sure is the bb.

LowCel 

If I had my choice I would go with square taper over ISIS any day. Unfortunately the nicer cranks are not available with a square taper. I was able to ride square taper bb's for years with no problems at all. I consider myself very lucky if I am able to get a single season out of an ISIS bb. All ISIS did was try to correct a problem that did not exist. Same as octalink.

If square taper was so bad I am pretty sure that Campy would have switched to another type bb by now. However theirs are still square taper and you very rarely ever hear of anyone having a problem with
one of them.

LowCel 

You may just need to grease the threads of your bb. A lot of times that takes care of the creaking noise, if that doesn't do it try a little plumbers tape. I use that on all of my bottom brackets.

C Law

or Phil Wood. his BB's are kinda ok too.

I would love to see a high end crankset (outside of the singlespeed world) in Square taper. Never gonna happen though.

LowCel 

Didn't even think about phil wood, those things are awesome! I've never run one but if I ever go single speed I will probably end up with one of them.

PA28Scuderia

Ok, I ended up getting the crank puller and the bottom bracket tool today. The cranks were off with ease and I'm in need of a wrench for the bb tool (I'm at college so pretty much all my tools except for the new ones and my alien are at home). In the meantime I was looking at the Park Tool site and they said I need grease, anti-seize, and a thread locking compound. I figured I would need the grease, but is the rest neccessary?

Raiyn

Not always the case. There are some really ****** ISIS BB's out there just like there are some awesome square tapers out their (see Race Face)
Low level / generic BB's can be terrible REGARDLESS of type
Exactly right. They may not be as stiff as ISIS, but they certainly work. They were a VAST improvement over the previous cottered cranks. While in many cases splined is superior, there are as many that go the other wayA common occurance with an improper assembly / service.
Same hereI do have to admit that my Hussefelt / Gigapipe Team DH combo is a lot stiffer than the previous crank / square taper BB which isn't a bad thing on a trail bikeI've had excellent luck with my Truvativ Gigapipe Team DH. Granted I bought it for strength and the added bearings not light weightCertainly true.
Much cheaper than replacing the whole bit and it works most of the time