HELP! Clyde killed a crank?
Hey all. Relatively new to mtbing. Im a big boy, 285, 6'5". Yeah I know BIG. Have a new Jamis Durango with a Truvative IsoFLow 44T crank set that seems to be clicking like crazy under load. I would liken it to the chain hitting the der. guard intermittently or maybe slapping against the bars while riding across a rocky area. Just imagine click click clickity click. I know its not doing any of those things mentioned above. The crank on the ring side has developed some play, and it think I might have done the bearings in? I have ridden in the wet conditions here in S. FL and I do not lube that area or clean after rides. Incidentally I just got a new SRAM der. set front and rear X-Gen and X9. Could the mechanic not have adjusted them right maybe? I have never worn out a part yet and I do ride a local technical park like I am going for broke, but then again my knowledge or skill is not great enough yet to really hammer on the bike. If in your opinion I have wasted this crank does anyone recommend the Truvativ Hollzfeller with one of those bearing systems?
Need some advice.
Hey, I'm only 6' and 270 so I might not be totally qualified to answer but I'll do my best.
First note - the Isoflow is what Truvativ calls a "comfort bike" crankset. Being thrashed around by a 285 pound guy sure ain't comfortable. Also, the Power Spline bottom bracket is what they call their "entry level Cross Country, Road & Trekking system" and is also not compatible with a big beefcake beating the hell out of it (from one beefcake to another).
The noise you're hearing is likely coming from the bottom bracket, as you suspected. It can be coming from one of two distinct places though - the bearings (not likely) or the interface between the crank and the BB. The spline interface on that bottom bracket isn't really designed for the kind of force you're putting on it. Tighten your crank bolts and see if it makes a difference. Pull the crank, lube the spline, retighten and see if that helps.
I'd upgrade though. I know that you've spent money on the sexy upgrades with your new derailleurs (how do you like the X9? I've been thinking of getting them myself) but you'll be a lot happier with a seriously stong crank/BB assembly underneath you. If you're not anti-Shimano, an XT crank with the outboard bearings is super strong and not super expensive. I love mine, there's zero flex when I hammer it. A Hone or Saint setup would also rock, but might be a bit overboard for your Durango. If you're not a Shimano fan, Trvativ and Race Face both make similar styles. If you really don't want the outboard bearings, any strong crank with an ISIS or Octalink Bottom Bracket will work great. But that PowerSpline BB you have now will not stand up to your punishment for too long.
One last note - many times people have torn whole drivetrains apart looking for an elusive clicking sound, spent hundreds of dollars on new parts, only to find out that the clicking was coming from their pedals. Pull 'em, lube 'em, slap 'em back on and see if it doesn't go away before you spend all the time and money on all that other stuff.
Good luck and have fun.