My 2014 Specialized AWOL came with an FSA Omega MegaExo 19 triple crank and an FSA BB-4000 bottom bracket. I bought the bike in October and in March I started thinking about doing some post-winter maintenance. One of the things that I wanted to do was remove and examine the bottom bracket. Since I was not familiar with outboard bearing bottom brackets, I did some research about the BB-4000 bottom bracket, and here is what I found out.
At the first glance, the BB-4000 looks just like a Shimano Hollowtech II bottom bracket. It looks the same and it takes the same tool to remove or install it. You may get a warm, cozy feeling that you have something that is easy to service and replace. Wrong! The biggest problem is that, unlike Hollowtech II bottom brackets and cranks (and also unlike other FSA MegaExo bottom brackets and cranks), the BB-4000 is designed for crank spindle diameter of 19mm (whereas HTII system is for 24mm spindles). As far as I know, the BB-4000 is the only bottom bracket on the market that can be used with 19mm crank spindle, and the Omega crank set that I got is the only crank set on the market with a 19mm spindle.
This means that you have a system that is only compatible with itself. Good luck finding the BB-4000 or the Omega crank in stock at any local bike store; all the stores I phoned told me it was a special order item. Not only that, but both FSA items are priced two-three times higher than comparable items from Shimano. For instance, you can get a Shimano HTII bottom bracket for $23, but the BB-4000 costs above $60.
There also is a philosophical problem. The Specialized AWOL is a touring bike. Touring bikes are traditionally designed with components that are easy to replace even in a small town bike store. What are the chances of quickly replacing the BB-4000 if it breaks down in the middle of a tour? That’s right, zero! Good thinking, Specialized, whoever made this design choice for the AWOL deserves a round of slow clapping.
And a special round of slow clapping goes to the folks at FSA for creating this non-standard standard. Good job guys, why did you do that? Is the 19mm spindle that cheaper to make than a 24mm spindle? Or, perhaps, the plan was to sell the system to OEMs so that consumers would be locked into this inferior system?
If you are reading this, the chances are that you got the 19mm MegaExo system stock on your bike, because I cannot imagine why anyone would install MegaExo 19 system by choice. Rather than feed the system by buying overpriced bottom brackets, I suggest that you chuck both the bottom bracket and the crank set and replace with something more reasonable. I bought a Shimano 105 series 5703 crank set with a matching HTII bottom bracket for just over $100 on Ebay. This cost me less than replacing the BB-4000 twice, and it gives me peace of mind knowing that I am using parts that are easy to replace at any moment, should they break.
p.s. When I replaced the FSA BB-4000 with a Simano HTII bottom bracket, I discovered that the bearing in the left cup of the BB-4000 was completely seized. The crank was rotating in the inner diameter of the left bearing like in a sleeve bushing. This happened less than six months after I bought the bike, but to be fair I rode it though the winter in Toronto, which means a lot of snow and salt. Not sure how indicative this is of the quality of the BB-4000 bearings. Perhaps the HTII bearing would have seized the same way, it’s hard to know. I’ll have to ride through the 2015/16 winter with the Shimano bottom bracket and find out.