frankgg

My entry-level road bike came with a Truvativ bottom bracket cartridge w/ square tapers, its been creaking a little so I want to replace it.

I know I need to get the correct length cartridge, but I know nothing about which makers/brands are good for the money.

So far all I know is I can pick up a replacement Truvativ for like $12 or a Shimano BB-UN55 for $25... Is there any others I should be considering or should I just grab the Shimano and not worry about it?

wrk101

UN26: Available on line for $10. I use a lot of them.

demoncyclist

A creaky BB doesn't mean it needs to be replaced. Try wrapping the threads of the cups with a little Teflon tape and re-installing. Then make sue that your crank arms are torqued properly and that the pedals are also on snugly.

DannoXYZ 

Crankarm-to-spindle creaking is much, much more common than bottom-bracket cup-on-BB-shell creaking. It's like an 80:20 ratio. If you used a small L-shaped allen-key to install the crankarm bolts, you definitely didn't get enough torque on those bolts. They will loosen and creaking will result. Oil or grease on the tapers may mask the noise, but it's not really solving the real problem: insufficient torque on the crankarm bolts. Here's a list of common torque-values for various fasteners on a bike: Park Tool - Torque Specs.

Metal fasterners are like really strong rubber-bands. You need to stretch them in order for them to develop enough clamping-force to generate enough friction to hold everything together. The crankarm bolts require an automotive-style 3/8" ratchet wrench to generate enough torque. Just do a search on here for "loose crankarm" to see how common an issue this is.

gyozadude

+1 on torquing BB cups and spindle bolts to spec. It's important.

Also, if you are looking for the correct spec for a replacement BB, then you can pull the crank arms, and then remove the BB and inspect it (provided you have the tools). The label on the inner shell should have the spec for spindle. Even if the BB seems good, I usually stock a replacement unit so it's on hand when I do need to replace it. And I don't spend a lot on a cartridge BB. Most seem to be able to easily last a couple of years of considerable use, even for a big guy like me, plastic, steel or alloy cups. The Shimano UN26 is great because it's cheap ($10) and widely available. Truvativ LE and Shimano UN55 are also very economical but have metal/alloy cups ($20), and the IRD units with alloy cups and hollow CrMo spindles are lighter and have a nice fit/finish but only run around $35 - $40.