Similar Products Used: Used XT BB for years no problem...
Bike Setup: Specialized Enduro
a Weekend Warrior
Date Reviewed: April 26, 2006
Strengths: Light, Light, Light, did I mentioned its very light.
Weaknesses: bearings went out within less than a year.
I've noticed a grinding feel after about 6 months of using, I only ride on weekends and I have 2 bikes, so that being said I dont use this bike bike often, Its actually my cross country bike, no jumping no abuses here. I followed the direction on rebuilding make sure you follow all directions, and all hell came loose, bearings were all over the place, drive shaft bearing cup was a nightmare to come off. So keep this in mind its not as durable, very expensive, hard to rebuild and often it needs, and finnaly did I mentioned its very expensive.
Bike Setup: Evil Imperial, sherman breakout plus, mag-30 rims, chris king original hubs, 3 piece race face cranks, diabolus stem. etc...
a Cross Country Rider
Date Reviewed: December 18, 2001
Strengths: light weight, reliable
Weaknesses: square taper
I purchased this because it is light weight and it has the grease guard feature for servicing. Because this bottom bracket allows you to adjust chainline, it took me a while to get the set up dialed in when I installed it. Several times I had to remove the cranks and adjust the cups so I could get things centered. Shimano bottom brackets are easy, but they don't provide for fine tuning either. Once installed, I have not had to touch this thing...no creaking, no relubing, no play, nothing. That is what I want in a bottom bracket. Plus it's a bonus if it is light weight. It would be ideal if this had an Isis crank interface, but I bought this because I didn't want to replace the cranks I already have (which have a square taper). One last thing to note, I had to rig up a "seal" for my grease gun to allow me to inject grease. It would be cool of these came with a hollow crank bolt that had the grease guard zerk in the end, that way you could service the bottom bracket very easily.
Bike Setup: voodoo bizango, steel hard tail, race face cranks
a Cross Country Rider
from rochester mi usa
Date Reviewed: October 6, 2001
Strengths: light weight, service
Weaknesses: relies too much on BB shell of frame for stiffness won't stay tight
This design is nice and lightweight, but it seems to rely too much on the frame's BB shell for stiffness. I installed this thing over ten times in my bike. No amount of loc-tite, grease, tape, torque, etc could keep this thing from creaking after the first ride. Poor customer support too. I got a regular stressed-shell BB, a race face Chromo, and have had NO creaking since. No amount of weight savings is worth rebuilding the drivetrain every other ride.
a Cross Country Rider
from Portage, IN USA
Date Reviewed: February 21, 2001
Strengths: Yow! This thing is super light! It can be freshly lubed in about 10 minutes without getting your hands dirty! Bearings are easily replaceable, and it's adjustable too. Yow! This thing is SUPER LIGHT!
Weaknesses: Uh, um... it's not for grease fetishists. If you like to get greasy, get one that needs to be taken apart to re-grease.
This BB is light, cool looking, easy to service, and basically the shiz-nit. Buy it, and revel in your newfound lightness and upgrade to full bike-weenie status. Let's face it... if you're buying a product because it's good, even if it's "invisible" on your bike, you're one step ahead of all the folks buying purple anodized brake levers and those stupid machined pulleys. This thing rules.
Weaknesses: You have to maintain this product. So if you are the lazy type, maybe this is not going to suit your needs.
I bought this as part of a weight reduction program for my bike. At 143 grams per the digital scale, I feel this qualifies as light weight. This product also holds up to the rigors of riding wet and muddy conditions for 6 months of the year.
Bike Setup: '00 Specialized M2 frame, XTR Drivetrain, Avid brakes and levers, Easton CT2 handlebar and seatpost, speedplay frog pedals, Sella Italia Flite saddle, American Classic BB.
Date Reviewed: September 21, 2000
Strengths: Light weight adjustability old school flavor for new school fools Greasy ports
Weaknesses: expensive square tapers soon to be history
The adjustability of this Bottom Bracket allows you to use it with E-type Front Deraliurs (ie lock rings on both sides) the design of this BB hasn't changed in years( ie proven design) Use locktight on the cups to keep them in place as the directions suggest. Happy railing.
Similar Products Used: every other bottom bracket you can think of
Bike Setup: Gucchi Ti frame w/ Marzocchi Z2
Date Reviewed: September 21, 1999
Strengths: The lightest product on the market A great value for the money Extremely durable Adjustable chain line Easy to relube
Weaknesses: You do have to relube it more often then mot BB's
This is far and away the best bottom bracket on the market. In the past I have had horrible luck with numerous bottom bracketsand would be hard pressed to get more than 3 months out of one before it would be time to warrenty it. With the American Classic I have not had anything close to a problem after two years of constant use in some of the worst conditions one could fathom. The AC BB is also the lightest on the market which is nice for any one who is counting their grams. The price of it is also less than most of the other nicer bottom brackets avaible. The ability to adjust the chain line is also a great plus to be able to get the quickest front shifting possible. Beyond a shadow of a doubt this deserves the highest rateing possible. I have convinces four of my friends to buy the AC BB and all of them are equally as pleased as I am.
Similar Products Used: Shamano LX, XT, XTR Syncros Ti
Bike Setup: Trek carbon hardtail Sid fork, chris king headset and hubs, ti spokes, x517 rims, Moots ti seat-post Ibis stem, Tittec 118 bar XTR derailer, Zipp carbon cranks,
Date Reviewed: July 15, 1998
After going through over a half a dozen bottom brackets in the past couple of years this is the first one that I have had no problems with. It's chainline adjustibility is also a great plus and its weight is also a bonus. For the money this seem to be as good as any other on the market.
Date Reviewed: December 18, 1997
I replaced my Shimano BB with the AC model over a year ago, after wearing out the bearings on my old one. It was one of the lightest bottom brackets I could find, and the titanium stands up to anything I can dish out. It was very easy to adjust the chainline when I installed it, and I haven't had to mess with it since. The bearings are very smooth, and lubrication is a lot easier than with the Shimano. I tend to be hard on my gear, and I expect it to last. This bottom bracket hasn't let me down.
a cross-country rider
Date Reviewed: November 5, 1996
Don't get a new bottom bracket just because you think it's cool. I only got mine because my old BB died and this was available.Compared to a Shimano BB, the American Classic _can_ last a whole lot longer, as long as you keep after it. The spindle is hollow and has allows you to inject grease without dissasembly. It's very similar to WTB/Suntour Grease Guard except that A.C. expects you to remove the crank bolts every time you shoot up (as if). Just get banjo bolts at your local hardware store or scrounge up some old WTB hollow crank bolts with the grease port built in.The biggest negative is flex. Titanium bottom brackets are flexier than steel. Period. There's no escaping the facts. Fortunately, I don't mind it. The good part is that after a year of very hard riding, racing, and trials with a 170# rider the bottom bracket is unbroken. That's pretty darn good performance for such a lightweight part.The bearings are very nice, and standard size for easy replacement. I've had mine for over a year on the first set and they're still good, though. Another neat feature is that there's an ajustable cup on BOTH sides. You can fine tune your chainline any way you want.
I have a GT Ti bottom bracket that I would like to replace the bearings on. The sleeve is an exact fit between the bearing so there isn't a good way to hold the bearings while the spindle is pressed out. I have heard one reference to using a vice to clamp the bearing itself. I was wondering if anybo ... Read More »
I just got a Motobecane Ti frame and it gas a hole that looks like it was used in manufacturing in the bottom of the bottom bracket right near the serial number. I was wondering, is this normal and if so why is it there?Read More »
NEW 2008 CRANK BROTHERS COBALT ISIS TITANIUM Bottom Bracket
I bought this bottom bracket for a new bike build, but decided to go with a different BB. Still in box with all factory documentation.
Actual weigh ... Read More »
I pulled an old Shimano XT ES-70 bottom bracket (Al endcup) out of my Ti frame and was shocked at how poor the Al end cap fared after years of use. There is no drain hole in this bottom bracket but apparently plenty of crap got in from the seat tube (?) and it looks like water must have been trappe ... Read More »