Bicycle Mechanics - Adjusting crank/gear play?

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View Full Version : Adjusting crank/gear play?


thatguysmells
10-28-10, 09:59 PM
Hey guys, this is only my second thread so please forgive me if this has already been answered a hundred times. I'm not even sure how to describe my problem that well but here we go...

My bike is fairly new, I've only had it for a few weeks and let me tell you, I am in bicycle heaven. I absolutely love commuting on my bike. It's great! Anyway, my question is this: I'm experiencing some "play" from the crank or gear. For example, if I coast and then start to peddle again, there is a noticeable "clunk" as if there is some play in catching the gear from a coast. It also happens if I peddle back and then forward again, there will be a clunk from the slight play in the gear. I'm not sure what you would call this but I hope I'm describing it correctly. Thanks in advance for any and all help! It's greatly appreciated! :o


Bezalel
10-28-10, 10:35 PM
It sounds like you are describing the symptoms of "cable stretch" in your rear shifter cable. When your rear shifter is in one of the middle gears make sure that the chain is running straight from the rear cogs to the jockey pulley. If it is not running straight you will need to adjust (tighten) the cable tension. This is normal on new bikes and most LBSs offer a free tuneup to adjust for break-in. (It's probably also happening while you pedal but don't notice it.)

thatguysmells
10-28-10, 10:48 PM
I noticed that if I run the crank backwards until I hear the railer click and then push forward there is no play. But, if I try to push forward on the pedals before I hear the click, there is noticeable play in the crank until it catches and I feel resistance.


Bezalel
10-28-10, 11:02 PM
I noticed that if I run the crank backwards until I hear the railer click and then push forward there is no play. But, if I try to push forward on the pedals before I hear the click, there is noticeable play in the crank until it catches and I feel resistance.

That's normal. the rear wheel is acting as a ratchet. Ratchet (and wheel) designers have to determine how much backlash (or how much you may have to pedal before the pawl catches) should be allowed. Having very little backlash produces alot noise and friction while coasting but the pawl catches sooner once you start pedaling. Allowing more backlash produces for quieter and smoother coasting at the cost of not engaging immediately when you start pedaling.

thatguysmells
10-28-10, 11:03 PM
Is there any way to adjust that?

Bezalel
10-28-10, 11:10 PM
No. It would require a new freehub or freewheel (you need to replace the entire ratcheting mechanism).

thatguysmells
10-28-10, 11:12 PM
Oh no! Hmm, what is the free wheel system like on higher end carbon bikes? Do they also have that "play?" My bike is a 2011 Specialized Allez Steel.