# Chain Slack while backpedaling



## tommyrhodes (Aug 19, 2009)

I'm sure this is a common problem but I tried searching for previous posts and could not find an answer.

My buddy did a hillclimb today and about halfway up he started complaining about his chain. I looked at it quickly and realized that it seemed his cassetted did not want to coast backward. The bike would roll and coast, but if he tried moving the pedals in reverse fasion, the chain would go lax and hit the chainstay. Any thoughts? Also, about 2 minutes into the ride his chain fell off. Admittedly, it was a short way into a big climb after a downhill, so I'm pretty confident that the chain fell off because of his shifting choice. I've got my bike up on the stand right now but would like to have his fixed tonight. 

Thanks in advance guys.


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## PlatyPius (Feb 1, 2009)

freehub is all gummed up with nasty old grease, or it's just going out. Either way, a disassembly is in your future.


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## tommyrhodes (Aug 19, 2009)

Damn. This bike is only a few months old. He's put less than 300 miles on it. It's shimano components on a Giant Defy. This is nothing short of a tragedy...


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## PlatyPius (Feb 1, 2009)

If it's that new, that's different....

It could just be new-stiff, or the derailleur could be out of adjustment. If the derailleur is off, you can't back-pedal easily.


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## Mr. Versatile (Nov 24, 2005)

Try to duplicate it on a repair stand. Take a look at what the chain is doing. Is it catching on something? Take a look at how it goes (backward) through the rear derailleur. It's possible the derailleur is out of adjustment, bent, or maybe the hanger is bent. Check the chain for a stiff link.


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## FBinNY (Jan 24, 2009)

It could be a sticky freehub, but that would also cause the top of the chain to slacken when coasting. Since that doesn't seem to be the case, look elsewhere. 

Possibly the RD pulleys are sticky, or the chain is stiff, from lack of lubrication, or because silt and fine dirt particles have lodged between the plates. Either of these would make the chain resist back pedaling, while not affect coasting. You wouldn't notice a problem under power because those forces are high enough to overcome the resistance.

My guess is that it'll be the chain (but then I'm biased and always blame the chain lube), what does he use as a chain oil?


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## pdh777 (Oct 7, 2005)

Could also be that you when you out the chain back on the bike you did not route it through the pulleys properly. Check the chain routing - Good Luck.


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## tommyrhodes (Aug 19, 2009)

The bike has 300 miles on it and I clean and lubed the chain myself less that 100 miles ago. Since then it's been nothing but clean and sunny riding. Chains never been off either. I'm gonna throw it up on the stand tonight and take a look at it. My thoughts are a funky derailer but I'm not sure yet. 
When I first started in cycling about 3000 miles ago the guy at the bike shop sold me a big bottle of finish line dry and dirty. It's wax based and I'm not really happy with it. It's just about empty so I'll be in the market for a new lube soon. perhaps even chain-l.


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## tihsepa (Nov 27, 2008)

I say the rear derailleur is out of wack just a little.


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## muscleendurance (Jan 11, 2009)

PlatyPius said:


> the derailleur could be out of adjustment. If the derailleur is off, you can't back-pedal easily.


this^ is most likely, have to ask though, who backpedals on a climb  WHy people why?


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## martinrjensen (Sep 23, 2007)

While I agree with you on why do it on a hill, if it does it on a hill, I bet it does it on the flats and it's most likely too much resistance in the freewheel. which means to much grease, dirty grease, or wrong type of grease. I suppose there could be a mechanical issue too, but it should be pretty easy to ID if you take the wheel off the bike and spin just the freehub. try to compare it to some friends (known good) freehub too.


muscleendurance said:


> this^ is most likely, have to ask though, who backpedals on a climb  WHy people why?


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## tommyrhodes (Aug 19, 2009)

Well, I frequently backpedal during a tough hillclimb if I'm in a downward slope of road. nice to feel the legs doing something other than battling in the same direction.

Either way, I finally had the time to throw the bike on the stand. Somehow the dorkdisk was knocked loose and was rubbing against the spokes. This was giving just enough pressure to keep the derailur tension from spinning the freehub. I don't know how the hell he did not hear it the whole way up the moutain though lol It would have driven me nuts. I can't get the lockring off his with a screwdriver and hammer though. So it looks like I'll be heading the the lbs before work to pick up a lockring tool.


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## old_fuji (Mar 16, 2009)

tommyrhodes said:


> I can't get the lockring off his with a screwdriver and hammer though. So it looks like I'll be heading the the lbs before work to pick up a lockring tool.


if it doesn't work, get a hammer


if it still doesn't work, get a bigger hammer.






although, my experience with freewheels and stuff is that you're much better off with the proper tools.


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## tommyrhodes (Aug 19, 2009)

Yea I've gotta agree with you there fuji. Especially on someone elses bike. I wanted to experiment with my rear cogs this winter anyway so it should prove to be a worthwhile investment.


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## dave699 (Oct 21, 2009)

tommyrhodes said:


> I can't get the lockring off his with a screwdriver and hammer though. So it looks like I'll be heading the the lbs before work to pick up a lockring tool.


Hold on - is it a modern Shimano cassette? If so, I would recommend a chain whip, a wrench, and a Shimano-compatible cassette lockring tool (Park Tool FR-5G, for example). The tool is probably $5-10 at your LBS, and I'd be surprised if they didn't have a few for sale.


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## FBinNY (Jan 24, 2009)

tommyrhodes said:


> The bike has 300 miles on it and I clean and lubed the chain myself less that 100 miles ago. Since then it's been nothing but clean and sunny riding. Chains never been off either. I'm gonna throw it up on the stand tonight and take a look at it. My thoughts are a funky derailer but I'm not sure yet.
> When I first started in cycling about 3000 miles ago the guy at the bike shop sold me a big bottle of finish line dry and dirty. It's wax based and I'm not really happy with it. It's just about empty so *I'll be in the market for a new lube soon. perhaps even chain-l*.


Don't tease me. 

I didn't suggest this earlier because I gave you credit for good overall maintenance, but if the RD is out of trim slightly it would increase drive train friction, not enough to affect normal riding, but enough to cause the backpedaling problems.


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## tommyrhodes (Aug 19, 2009)

Yea it's a modern shimano. I've had luck in the past with a "chain whip" and screwdriver. If you get the screwdriver at the right angle you can simply tap the lockring off. No luck on this one. I dont' have chain whip though, I just wrap an old chain around the cassette and then nail the other end of the chain to the table. Usually works fine lol. Gonna find time to stop by the LBS. Went riding before work so I did not have the opportunity to stop in. 
I was only busting your chops FB. I've heard nothing but great things about your lube. I really am considering ordering some it's just not high on the priority list yet. My bottle still has another lube or two left in it.


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## pdh777 (Oct 7, 2005)

Glad you found the problem - probably a good idea to get rid of the dork disk and adjust the RD accordingly.

FWIW - wax lubes will build up gunk quicker than any other kind. Try something light like ProGold, much better.


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