Hub Question/Pedaling

[YellowAndRed]

Hi all,

please forgive me if the answer to this question can be found somewhere else in the forum. I did a quick search but didn't have much luck.

I'm not sure how to explain the problem because I'm not too familiar with all the terms and the names of the parts. So, try to bear with me. My only source is this forum and the Big Blue Book.

The problem that I have is the following:

When I pedal with very high cadence at a small gear or when I pedal hard (usually standing up at a high gear), it seems like for 1/16 or 1/32 of the pedalling motion moves the sprockets, but doesn't engage the hub itself, which of course results in a "free" pedaling for the lack of a better term. This pedaling motion doesn't move the rear wheel either as a result of the hub not turning. It makes it really hard to ride the bike going uphill while standing up, or at a very high cadence.

I was wondering if this was a very common problem and what I could do to fix it.

Thanks in advance!

Oytun

 

[cucamelsmd15]

I seem to recall an article about this on Sheldon Browns site, but I cant seem to find it now.

Basically, if I remember correctly, it has to do with the freehub not engaging. Its more noticible on a mountain bike, with higher gears because you have to turn the gears farther in order to engage the freehub. Its not as noticable on road bikes because of the gears we use, save for the exception you just mentioned.

Yeah, something like that.

 

[Insight Driver]

Something doesn't make sense. Does this happen for every revolution of the crank? If the hub pawls are engaged there shouldn't be any sense of crank moving without the wheel going anywhere for any portion of the revolution of the crank. Does it happen when immediately after you have shifted a gear? I get the feel of motion when the chain is dropping from one cog to the next but I understand why that is so. It's most noticeable when dropping from the large chainring to the small chainring on my compact drive setup.

If this happens to you regularly, how old is your bike? It may be possible that your hub needs service.

 

[artmichalek]

I was wondering if this was a very common problem and what I could do to fix it.

It sounds like you have a buildup of dirt and old grease in your freehub that's preventing the pawls from engaging properly. Park Tool has the instructions for cleaning it out:
http://www.parktool.com/repair/readhowto.asp?id=45

It's also possible that the pawls and ratchet are worn out. Depending on how old the hub is you might be able to get replacements.

 

[YellowAndRed]

It sounds like you have a buildup of dirt and old grease in your freehub that's preventing the pawls from engaging properly. Park Tool has the instructions for cleaning it out:
http://www.parktool.com/repair/readhowto.asp?id=45

It's also possible that the pawls and ratchet are worn out. Depending on how old the hub is you might be able to get replacements.

Thanks a lot for all the responses. I really appreciate the help.

It happens every time I pedal, so it doesn't have anything to do with shifting or anything like that. For instance; let's say that I'm coasting and when I start pedaling again, the first 1/32 or 1/16 of the pedaling motion does not turn the wheel. So it takes a while for it to engage. A very small amount, but it really affects my pedaling rhytm and motion especially if I'm standing up, going uphill.

I am assuming the problem is old grease or dirt buildup. I will keep y'all updated.

Thanks again!

Oytun