Clydesdales/Athenas (200+ lb / 91+ kg) - Ugh...it happened again! (crankarm issues)

So the other day my left crankarm came off (!!!) after a short, but steep climb. I have been pushing myself and went up a steep hill on my second chainring and in the lower-center of my rear cog (the chainline was pretty straight). Anyway, I pulled over, re-attached the crankarm and took the back/slow way home just to be safe. I didn't get a chance to get my bike to the shop over the weekend, so last night I took a look at it...took the crankarm back off...made sure everything "looked right"...re-attached the crankarm (tightened evenly)...and then gave everything else a "once over". Today I went back out and in less than a half-mile I looked down and the crankarm was coming off again! I wasn't even pushing real hard yet!

My neighbor is an avid cyclist, so he and I were talking...he said that there has got to be something wrong with the crankset...even being an FSA Omega. I'm planning to get my bike back out to my LBS tomorrow as it's been less than 60 days since I've had the bike and they do a free tune-up within 60 days. I looked at the crankarm and it has a sticker with a weight limit of 110 lbs. At 265 are there any cranksets that shouldn't make me nervous????

If you ride it loose, you have ruined the crankarm, time for a new one. Maybe it's time to upgrade to a 2 piece with outboard bearings. The Shimano Hollowtech II put on my Cross Check has been holding up nicely.

I've heard lots of negative stuf as far as FSA, but ostly form offroaders. I had the Bonti onmy Lemond, which actually is a Truvativ BB. Whenit was time, I replaced with an Ultegra outboard bearing setup. I pikced it up on an ebay online store "wheelandsprocket" Paid $149 with the BB included. Much better and much stiffer and durable. No slop and rock solid.

Took it to the shop paid $25 to install. The outboard bearing stuff is nice!:thumb: I myself would pass on the aftermarket stuff.:(

So the other day my left crankarm came off (!!!) after a short, but steep climb. I have been pushing myself and went up a steep hill on my second chainring and in the lower-center of my rear cog (the chainline was pretty straight). Anyway, I pulled over, re-attached the crankarm and took the back/slow way home just to be safe. I didn't get a chance to get my bike to the shop over the weekend, so last night I took a look at it...took the crankarm back off...made sure everything "looked right"...re-attached the crankarm (tightened evenly)...and then gave everything else a "once over". Today I went back out and in less than a half-mile I looked down and the crankarm was coming off again! I wasn't even pushing real hard yet!

My neighbor is an avid cyclist, so he and I were talking...he said that there has got to be something wrong with the crankset...even being an FSA Omega. I'm planning to get my bike back out to my LBS tomorrow as it's been less than 60 days since I've had the bike and they do a free tune-up within 60 days. I looked at the crankarm and it has a sticker with a weight limit of 110 lbs. At 265 are there any cranksets that shouldn't make me nervous????

Hard to believe that anyone makes a crank with a weight limit of 110lbs unless it is a kids bike. They need to be torqued down with a torque wrench. This look to be a poor installation job, and it may be ruined as mentioned above. As Beanz said, the Shimano stuff is much better then the cheap aftermarket cranks.

The FSA Omega is the MegaExo BB equivalent to their JIS Square Taper Vero crankset. It's not expensive, but it will hold up well if it's maintained (meaning - properly installed and keep the torque correct on the retaining bolts.) I've got over 9000 miles on a Vero crank and they're barely starting to give a little flex now.

Unless the 110 sticker specifically says "rider weight limit" (I'll wager $5 it doesn't), then it's probably a b.c.d. indicator. The Omega is a 110bcd compact crank.

The sticker does not say that it's a rider limit, but I wasn't completely sure what it was referring to.

I've had the bike for about two months and I haven't gotten it back in for my first free tune up, so I'm planning to take it in today. I just wonder if this is something they'll take care of for free, or if they'll consider it something that I caused.

In terms of cransets...it sounds like Shimano is the way to go. What about Truvativ? (as it is used on Masi bikes)

If you ride it loose, you have ruined the crankarm, time for a new one.

Not necessarily true. I had similar problems with a square taper crank (Shimano Deore LX?) and a UN54 bottom bracket. Had the crank come loose a couple of times. The solution, for me, was to install the crank and torque the bolt to spec using a torque wrench. Never had a problem with it after that...

The sticker does not say that it's a rider limit, but I wasn't completely sure what it was referring to.

110mm sounds like the recommended length for the bottom bracket spindle. They range from 103-127mm, with 110 and 113mm being pretty common for road bikes with double cranks.

So, I took my bike to the LBS and told them everything that had happened...and the guy asked if I had put the other bolt back in. Hmm. I guess that was the problem! There is another bolt that apparently was lost the first time this happened. Since I didn't find it or even know about it (my fault, I know) it wouldn't stay on or be safe to ride. Hopefully now it won't happen again.

As for the sticker with the weight...I was wrong yet again. It says 95-130 in. lbs.

As for the sticker with the weight...I was wrong yet again. It says 95-130 in. lbs.

Torque setting.

If I were you, I would take it easy going down large, twisty hills for the next 100 miles or so. Putting that second bolt on there may have fixed the problem, but I agree with c_m_shooter, that once they come loose a couple of times, the crank-arm could be ruined. Those crank-arms have to fit very tightly with no deformations where the softer alloy metal of the crank-arm touches the hardened steel of the bottom bracket. If it works loose again, then the metal on the crank-arm is deformed beyond repair, and you at least need to get a new crank-arm for that side.


Be careful.

I'll see what they say tomorrow when I pick it up and go from there. Thanks everyone!