Chain slap advice

[Loggahead]

The age old PIA, chain slap...

So I have my chainstay covered already and even took my bike into the shop to have my chain adjusted because of it. Here's the deal: When in 2nd gear on my crankset, i get bad chainslap. I notice that it is not slapping my chainstay but is actually bouncing up and down right at my crankset. And instead of a simple "klak" its more like "ka-klak ka-klak ka-klak" everytime Im hitting any sort of moderate drop when in 2nd up front.

So Im riding more in 3rd (which really isn't a bad thing) but am wondering, am I just being picky? Or is there something else I can do or have done to minimize it while in 2nd? I realize those are loaded questions and likely not enough info, but maybe you can shed some light.

-logga

[superdave]

I'm sure since you've taken it to the bike shop, they've already checked to see if the chain is too long. But if you want to check for yourself, put your shifters on the two smallest rings (front and rear) and look to see if part of chain that is traveling from your crankset to your derailuer (the bottom of the loop) is rubbing the upper roller (or forward roller at this point) on the rear derailuer. If it is rubbing, you can shorten your chain. If not, that's not your problem.

[WILDBILL]

It could be that your middle chain ring needs to be changed.

[Loggahead]

So lets hypothetically say that its not my chain length. What other places could I start to look?

Bill mentioned my middle chainring, what could i do to verify that and what would need to be done to fix it?

Do you guys think Im being to anal about it?

[Pilotman28]

The only thing which is providing tension on your chain is your rear derailleur so the spring on it might be not as stiff as it used to be and it's allowing more movement. I don't hear a peep out of mine.

[natepac]

Do you guys think Im being to anal about it?

If figures that Pilot would be the 1st to chime in after someone mentions "anal"

Check the teeth on the 2nd chainring, some may be worn out.

[natepac]

sounds like you are getting chainsuck (http://www.fagan.co.za/Bikes/Csuck/) instead of slap.

[egordon]

Its summer time, the earth is closer to the sun .. there for the gravitational pull is greater causing your chain to sag and slap..

[Loggahead]

I'll check my teeth out.

If it makes any difference, I think the noise Im getting is a result of the chain bouncing off of my largest ring in the front from a horizontal motion. I noticed on my last ride at at least one point I felt the chain hitting my ankle as it was bouncing back and forth like crazy when I was in 2nd gear. Thus I just started riding more in 3rd...

[scratchndent]

Man up and convert to single speed and no more slap!

[ritebike]

I would take a look into several things. The first is, how old is the chain? It may have stretched, and need to be replaced. Next, check into the chain length. If the chain is to long, this could be the problem. Superdave described how to check for that. There may be a chance that your Der. is worn out. If that is the case, you may need to replace it. If it is a new Der., I am going to suggest this. It should fix a new der., or add a few miles to an old one. The "B" screw, which adjusts the tension on the pivot bolt spring. This is the screw that is closest to the cogs. It goes to the dropout. Don't turn it to much, it will effect you chain, and the contact to the cogs. If you turn it to much, it could cause your drive train to skip. If you have any questions, you can email them to me at ritebike@hotmail.com and you can also go to www.sheldonbrown.com for everything you need to know.

Later,
Dean

[Loggahead]

Thanks for all the advice everyone!

Just some background info: My bike is only a month old but I've already put 145 miles on the trail. Its an 08 GF 29er with SRAM x.5 on it.

Marty - Believe me, I have been thinking more and more about going SS. If I do go SS though, I won't have a geared bike at all in case I ever need one... that and Im still wondering how well I do with it. My best main loop time is now 50min 31sec.

Nate - Twice now, my chain has gotten sucked up when downshifting from 3rd to 2nd on my front der... I have noticed that beyond doubt all the noise is coming from the chain slapping around on my actual crankset rings...

[Pilotman28]

New chain dude. Have you tried a new chain? I know it'd be pretty crappy to have one go out on you but it's a friggin $20 part and it might make all the difference.

And next time you have to take your bike to the shop, take it to Mark at Truly Spokin' he's good.

[WILDBILL]

Its not your chain unless you have a noticable twist in it or something and if that was the case it would effect more areas than just the front. 145 miles on a chain is not real far by any means.

-Billy

[natepac]

Nate - Twice now, my chain has gotten sucked up when downshifting from 3rd to 2nd on my front der... I have noticed that beyond doubt all the noise is coming from the chain slapping around on my actual crankset rings...

3rd ring, when the hell do you use the 3rd chainring. i never used mine thats why i removed the excess chainring, also the 1st chainring as its pretty useless too. 1X9 seems to be the magic ticket.

[Loggahead]

The last few times I went out I used my third chainring almost about 80-85% of the rides! I only switched down to 2nd on Gorge and some technical parts. I decreased my time over those few rides as well and that was really the only big difference i made in my riding. I really picked up speed on the downhills as I was typically riding in 3 / 6-9 on like Pate, Chute, Cambodia, etc.

I really only tried it because I was tired of hearing my ka-klackin all the way down the trail.

[ritebike]

Loggahead,

After reading the past few postings, I would check you chain length, it may be a link to long. Coming from the factory, it is something that may have been over looked. Someone mentioned a twisted link, I don't think that a twisted link would cause chain slap, but it would effect shifting, and could cause skipping. As I have mentioned before, check your "B-screw" which adjust the tension on the rear derailler pivot bolt/ spring. The fact that your bike is so new, the chain lenghth, and the B-screw would be the first things that I would check out. Again I would check out the website that I mentioned if you have any issues.

Later,
Dean

[Loggahead]

Final verdict on this from Mark:

My chain length is perfect and the slap I am getting is normal. Again, the noise is from the chain knocking my 3rd chainring up front. My chain can't go any shorter as my rear der will be over flexed. Even though my chain is perfect length, due to my setup, I have to run a looser chain and thus it slaps when in 2nd up front and in 6-9 in back.

My options:

1. Run it, don't worry about it, or run in a different ratio if the noise bothers me.
2. Change from a 34T rear cassette to a 32T which would allow me to drop a link.
3. Run a single gear up front and keep the 34T in back

So, since the bike is brand new I will just run it and keep running my downhills in 3rd until I wear out the cassette. Then I will likely look at swapping to a 32T cassette in the future and possibly a medium cage rear der. I also am liking the idea of possibly going single up front.

-logga