difference in botom brackets

[taylor p.]

i need to buy a new bb and i am trying to figure what is the difference in bottom brackets. im thinking its weight and how smooth they are?
here is the bb i am replacing
http://wheelworld.com/itemdetails.cfm?catalogId=39&id=4135
and then their are all the other ones out there (that cost more). so what do i get when i pay more for my bb

[col200]

You're in luck with the squaretaper cranks. The ONLY bottom bracket (not X-type or similar) that I've ever liked is the RaceFace Taperlock. Still use one on one of my bikes and it's 6 yrs old...works great!

[DanB]

Your right spending more gets you lighter weight and better bearings. Keith Bontrager said it best "Strong, light, cheap, pick two." Some of the really nice square taper BB's are very expensive but they will last you a lifetime (or two), so you need to ask yourself how long this particular bike, crankset etc. will be in your life. If your plan is to keep the bike and cranks as lifelong partners and your going to hang onto the bike I would buy a nice one such as a Philwood (although it requires special Philwood tools to install), or something similiar, but more likely if this is a temporary bike, which most of them are, then I would look to get a more budget oriented BB. For about $20 to $30 you can get a Shimano UN52 or UN72 that will work great and last you a couple of years, maybe more. Just my opinion hope it helps. :)

[Kingbozo]

A somewhat related question-Some of the online "bike shops" are selling "XT Cranksets w/bb" Example http://www.performancebike.com/shop/profile.cfm?SKU=17731&subcategory_ID=5120)

I realize that these are the "new style" BB systems with the outboard bearings, but there is no options on these sites for sizing like there is on old style BBs. Is sizing now irrelevent with the new tech? Am I missing something?

[DanB]

A somewhat related question-Some of the online "bike shops" are selling "XT Cranksets w/bb" Example http://www.performancebike.com/shop/profile.cfm?SKU=17731&subcategory_ID=5120)

I realize that these are the "new style" BB systems with the outboard bearings, but there is no options on these sites for sizing like there is on old style BBs. Is sizing now irrelevent with the new tech? Am I missing something?

Yes sizing is a thing of the past. The crankset/BB combos come with spacers to compensate for BB shell widths.

[taylor p.]

i dont think i want it to last my life but 1 or 2 years souonds good
do you guys know of a web site that has good deals on square taper bb
(lbs wants about 40$ for one)

[Kingbozo]

Yes sizing is a thing of the past. The crankset/BB combos come with spacers to compensate for BB shell widths.

Sweet! The next question is: Would a new XT/BB combo be lighter than the old school (2001) Specialized Strongarm splined BB combo I am currently using?

[crux]

Sure its SPAM but just tryingto help a guy out.;)

Have a few Raceface Square tapers (Used yet in very good condition) $10

That or a Ti Philwood BB offset is for a set of White Industry cranks
New never used $100.

[tedsti]

Speshy cranks 774g + Shimano ES70 BB 260g + bolts 38g = 1072g

XT 760 crankset 870g

You would save 200g which is almost half a pound.

Sweet! The next question is: Would a new XT/BB combo be lighter than the old school (2001) Specialized Strongarm splined BB combo I am currently using?

[Heuy]

While we're on the subject, how is the durability/reliability of the newer outboard systems?

There's a lot of horror stories on mtbr.com. Maybe this is a case where the ones with problems are so muvh more likely to post, or maybe they're just that bad?

I'd like to save the weight, but if its going to be problems:confused:

[turbo_kitty]

i have installed over 20 outboard bearing set ups since they came out and have not realy seen any problems, but after being around for the advent of splined bb's and hearing horror stories about installing them, outboards are easy. i do however agree with the articles of late that say outboard bb's have very high friction and it is becomeing my beleif that there isn't enough stiffness gain to switch from square or splined bb's other than they look cool.

i know this is an off-road form but the vast majority of track racers on the velodroms of the world are still using square bb's and thoes guys and galls are putting huge amounts of torque on their machines and it looks as there is no to very little effort to switch to outboard bb's and cranks. anyway, most of your pedaling stiffness comes from the frame and not the cranks.