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To Thine Own Crank Be True: The Number One Creakiest Thing On Your Bike and How To Silence It (sadly, not for good).
Tighten down those Boas, boys and girls. Cinch up those helmet straps ladies and gents. Smack your quads and call me (big)daddy, let’s take this baby out for a (quiet) spin!
I’m not going to beat around the bush with this post. Well, except for that first spectacular paragraph, which is fantastic, but other than that, let’s get into it!
There are a pile of crank types out there and they are not all created equal. If you want simplicity that just works, you want Shimano. Lightweight, works spectacularly… and costs as much as an entry-level mountain bike? S-Works or Campagnolo Super Record. Next level, you can’t afford this $#!+? THM Clavicula. Reasonable priced but a tad heavy? FSA or Praxis for the alloy cranks. SRAM Red, Rival or the high-end FSA models are decent.
They all break down a little different and some are going to be more susceptible to collecting grit than others and grit is the problem. It causes more creaks in a bottom bracket/crank interface than anything else known to cycling – that grit can also be exceedingly difficult to get out of the little nooks and crannies of the bottom bracket so it quiets down, too. Every group has one of those cyclists who you hate to see get out of the saddle because you know, the second that ass leaves the saddle, their bike will sound like someone chewing on Pop Rocks with their mouth open.
The main key to a non-creaky bike is to keep that bottom bracket and pedal spindle clean and properly lubed. Most cranks only require loosening a bolt or two to get the crank apart (or two clamp bolts and a cap for Shimano – and that cap requires a specialty tool), but for my bang for the buck, my BB30 S-Works crank is the best, least maintenance crank I’ve got in the stable, then the cranks on the tandem (I’ve never serviced them in the four years we’ve had the bike and they’re still silent as the day I brought it home[!]). Most will let in a little grit or dust over time and will eventually start clicking and creaking. FSA and SRAM cranks have wavy washers to preload the systems, so there’s a rather large gap at the crank spindle that’ll let dirt into the works so those have to be cleaned often to keep them quiet.
Being the mechanic of the house, I won’t deal with a crank that has a wavy washer because breaking a crank down every time I run my bike through a puddle isn’t exactly my idea of fun.
Anyway, what’s important to know is that those quiet bikes don’t get or stay that way on their own. An S-Works crank will stay quiet on its own for the most part. A Shimano will need to be cleaned a few times a year. A wavy washer crank, figure every two or three weeks, maybe more (if you ride through a puddle). The point is, if you take care of your crank, keep it clean and lubed, it’ll reward you with not being the Pop Rock person in the pace-line.
What Makes a Bike Clunk When You Pedal? And There’s a BIG Difference Between a Clunk, a Click, a Tick and… Uh, Anything Else.
Were we simply talking drivetrains, I could write this post in two words because only the main culprit will make a “clunk”. “Ticks and clicks” take care of virtually everything else in the drivetrain. The two non-drivetrain related “clunks” are a quick release skewer being loose to a point of being dangerous and a loose headset. “Ticks and clicks” cover everything else there as well. The diagnosis of a loose headset is simple: grab some front brake and rock the bike back and forth. Place your right hand on the headset while you’re rocking the bike. If it’s loose, you’ll feel the slop in the system. Loosen the stem bolts that clamp to the fork post, tighten your stem cap bolt till the slop is taken up, tighten the stem bolts, and you’re done. Quick release is even easier. Give your wheel a side-to-side wiggle. If it’s loose, you’ll feel it. Tighten the quick release before you crash into something and don’t ever let your bike get like that again. You should be checking things like that routinely before you ride.
The main clunker is your crankset and/or bottom bracket bearings.
Road bike cranks tend to be relatively simple affairs nowadays. The pricier models, such as the S-Works crankset on my Venge, is ridiculously simple and impressively light. The cheaper the crank, the heavier and more complex they get, requiring special wavy washers and cap washers to keep dirt out. Cranks that require wavy washers are notorious for letting dirt into the system. They require regular cleaning to keep from clicking and ticking while the pedals go ’round. Your Dura-Ace, Ultegra, S-Works and SRAM Red and Force lines don’t require as much fuss.
We’re talking about clunking, though. Not clicks and ticks. Clunking is caused by a loose spindle or bearing. If the crank bolt isn’t tightened enough (and they require a hefty amount of torque, just look on the crankset and it’ll tell you how much), you’ll eventually get a little clunk at the top of the pedal stroke as power is transferred from one crank arm to the next – often in the left arm.
Now, on one hand there’s the simple fix; tighten the bolt. On the other, I like to go a little further and pull the crankset out, clean it, lube it and put it back together. If I’m going to be in there anyway, I may as well clean it out and do it right. I’m going to have to deal with it sooner or later anyway.