I recently bought a Kona Jake the Snake that came with FSA Gossamer MegaExo Compact cranks. There is nothing I hate more than seal drag in a bottom bracket and this particular set has that. I first experienced bottom bracket seal drag during the era of the ISIS bottom bracket. Most of the ISIS bottom brackets I have felt have not only had seal drag, but can be even hard to turn new out of the box. I even had one that is you held the bottom bracket in your had, and put a crank on the spline horizontal to the ground it stayed in place! . . . are they insane? . . . With all their talk of smooth bearing, any advantage from their smooth bearings is negated 20 times over by the seal drag.
Ahhhh then one day I saw a new invention called the external bottom bracket . . . and yes bearing as smooth as silk . . . looks like problem solved . . . well until I rode in the rain and let them sit for a week. One of the bearing completely seized up with rust . . . Oppppp my fault for being lazy, I've been around long enough to know, just because they are sealed bearing doesn't mean water-proof.
OK back to my point I recently bought a Kona, Jake the Snake that came with FSA Gossamer MegaExo Compact cranks and I noticed a lot of drag from the crankset. I took the chain off, and sure enough those cranks don't spin very well. So I had to investigate why don't these cranks spin . . . and since I own a bearing press to do the job why not?
What I notice different from my other set is FSA spec'd their bottom bracket with 2 more seals. I suspect probably because a lot of other people probably experienced rusts bearing with the other design so they fixed it. Other than me I don't know a lot of people that work on their bottom bracket much, for a majority of people it seems the bottom bracket is " install it and forget it" . . . ( But with all the talk of ceramic bearings of late, I'm surprised this one gets by people ) . . . You want maintaince free, well you got it, for a price . . . more seal drag. They added a seal inside the bearings to shield it from contaminates for inside the frame, and another inside the black plastic plastic shim/shield to double protect from outside contamination.
I found the most drag from the seals from the ones the protect from the inside contamination, they actually drag on the crank arm spindle. Well these got to go, I have a race next week and these are not going to wear-in in the next week, so these got to go. I pulled the bearings and removed seals.
Since I had the bearing out I looked at them, looks like white lithium, I also replaced that with Phil Wood grease. I think the Phil Wood grease will be a little more resistant to water than white lithium. I've already been down the path a craping out a set of these bearing, and even though they are sealed I know ever well it's no guaranty. Do you need to repack the bearing, probably not, but since I've craped a set out let's try something new.
The next seal I removed was probably very consequential, but since I've sworn myself now to Bottom Bracket guard duty I pulled them as well.
I pressed the bearing in, pressed those black shim/seal jobbys back in, assembled the cranks, and now it runs silky smooth and without a noticable amount of drag.
To not add confusion, I did put back on the seals to the sealed bearings I just removed to other 4 . . . for lack of a better word "safety seals". I put back on the other conventional seals. I just sworn myself to to devout maintanance of the BB, and why not since these cranks are so easy to take off. 2 pinch bolts and a set bolt and you good to go. No puller needed! . . . I love it!
It makes me wonder though with all the talk about ceramic bearing if they don't make the bearing with a little extra drag to make a broader contrast between the stock bearing and cermics. Obviously one advantage is ceramics don't rust so you can proably get way with just the outside seal. So are cermics worth it? . . . Well nothing in life is guarantied, I think over looked and probably greater benefit is they don't rust and if you not into maintanace, you might go through 3 bottom bracket during the year about the price of one set of ceramics with the benefit of less rolling resistance.
Well some of you might think I'm crazy, but all I know now my cranks turn silky smooth and they are still sealed.
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