Gossamer
I bought my first set of FSA cranks (Gossamer MegaExo) while working in the cycling industry. The non driveside arm used to loosen every 4th or 5th ride so I always had to be attentive. I finally ignored their recommended torque range and just tightened the snot out of them. That seemed to hold things together for a good season or two. Eventually though the torx wrench requiring bolt that helps to snug the non-driveside arm tight against the driveside arm spindle wore down to a round hole. Hey FSA, good idea to use
a. soft aluminum
b. a small hole with a less than standard torx fitting
After two years of use these cranks were removed and relegated to spare/emergency duty. As a side note, if you own FSA cranks, I would suggest having a spare or back up set handy because your cranks will inevitably fail. I recently re-installed the Gossamers when my FSA SLK cranks failed for good (see below). The loosening problem is back and the stripped tightening bolt is not helping things.
SLK
I bought these cranks when I built my sunny day rider. At the time, they were high end for my budget and they were fairly lust worthy (in my eyes at least) since they were new technology and carbon. On my maiden voyage, despite suspecting they may loosen (um, see above...) they stayed tight. I torqued them to factory spec after each of my first 3 or 4 rides and everything seemed good. On my 4th or 5th ride, I was about 20 miles from home when I noticed the non-driveside beginning to loosen. I didn't have an 8mm allen wrench (no stupid torx head needed on these) so I limped them home as best as I could. Ever since then the cranks have acted like powercranks with the non-driveside arm slipping forward and backward on the splined driveside spindle despite not being loose side to side. For a while I thought it was play in my pedals or the crank arm loosening again. It honestly took me most of the season to figure it out. Fortunately, about the same time that I figured it out I also be-friended a very nice FSA employee who got me the hook up on some K-Force cranks. The SLK's were initially shelved for a year and then shifted to the Gossamer bike when I got sick of the Gossamers loosening. Confused yet?
This winter, after a season of 'cross racing with the SLK cranks I finally called FSA to see what can be done. They were very familiar with my problem (because I am willing to bet it happens a lot) and have offered to replace the non-driveside crank arm. Apparently the aluminum insert on that arm is susceptible to greater wear (again, great thinking there) than the steel driveside spindle on which it is mounted. Thankfully I have those POS Gossamer cranks to use in the meantime. Oh, and yes, the Gossamers continue to loosen almost daily.
K-Force
Being the cream of the crop, I expected the K-Force cranks to work without issue. Since they were on my sunny day ride, I never really put them through any tough conditions but I still felt they were the most expensive and therefore the best. When I saw the super dooper close out deal from my FSA employed friend I jumped at the chance to get another set. They were to be used on my 'cross bike as it was reconfigured for a cross country adventure. The compact gearing allowed me to avoid the need for a triple ring and the bonus of being lightweight seemed like a great idea. Luckily they didn't fail until I was in the middle of f'in nowhere Indiana. I noticed some play in my pedal and thought it might be the cleat on my shoe. Nope. Maybe my pedal was unthreading. Nope. In fact, the pedal insert was coming unbonded from the crankarm. When I finally figured this out I called all the area shops to see if any of them might have a similar K-Force that I could purchase. Oh, did I mention I was in the middle of nowhere so I had very limited cell reception? When I finally got to Ft Wayne, IN I found my way to a shop that allowed me to take a new non-driveside arm from their inventory while my FSA friend sent them a warranty replacement. Honestly, if I didn't have that FSA friend, I probably would have been out some serious $. Then again, I never would have bought the K-Craps to begin with...
Thinking the worst was behind me, I continued on my journey. Within shouting distance of home (Hopkinton, MA) the other pedal insert came loose. FUCK! When I got home, I mailed the cranks back and requested a different model (SLK Light). Those went on ebay and I've been slowly working to eliminate all FSA cranks from my fleet.
Although some might say I am failing to accept blame, I think it is pretty clear when a company makes a shitty product. I've used dozens of other brands without ever having problems so I think it is fair to say, FSA CRANKS SUCK. Ask Ryan Kelly, he'd tell you the same thing.
Oh, but did you hear FSA is going to release a new 11 speed drivetrain? Yeah, remind me to rush out and buy that.
