Mega Exo Vs. ISIS

[jerman]

OK, first off I'm an idiot.
Next, I bid on two different cranks on ebay and ended up winning both.
The first crank is a Truvativ Firex SS and uses the ISIS BB.
The second crank is a FSA Afterburner and it uses the Mega Exo external BB.
Which would you use on a SS 29er?
I am leaning toward the FSA but wondering about chain line issues.
Any thoughts are appreciated.:)

[bdee]

You should be able to make either work. External BBs should have spacers to move the cups in or out depending on what you need. I'm running Truvativ Stylo external BB/crank on the 1x1 now with no issues (other than the crank bolt loosening up, which caused a wobble that allowed the chain to fall off a few times until I figured out the problem :o).

[Kopko]

If you ride lots you'll wear out one isis bb every month or two. Go with the mega exo.

[Tystick]

If you ride lots you'll wear out one isis bb every month or two. Go with the mega exo.

Not sure which BB you've used, but I might upgrade if it "wore out" after a couple months. Either one would work fine as far as chainline, but the external BB's have a ton of drag to them. Those exposed bearings require tight seals, any other BB spins much better. Unless you buy into the most over-hyped marketing BS of the year, you could buy a ceramic BB for $150-$200. Then an external will spin almost as well as a splined or square taper.

[Kopko]

I used an FSA platinum pro. Not a shotty BB at all and a quite expensive raceface one. Then I went back to squaretaper. Anyhow this I just my experience. I'd go with the stiffer crankset (mega exo) rather than the isis, regardless of extra drag.