Chain slipping on just one cog...

[jasonmason]

So I searched the archive but nothing really seems to sound just like this...

Yesterday on the loop my chain started slipping, but only when I'm on my middle ring up front and the midlle one in back. All the other gears are fine, and it only slips when i'm really torquing on it, hammering up stuff that I should be downshifting more for. Checked the rear der. adjustment, it's fine; no sticky links, no crap gumming up the cassette; teeth are worn in but not overly worn or bent.
I'm thinking maybe just that cog is wearing out on the cassette? I tend to abuse that one, torquing it quite a bit since i like to ride my geared bike like it's a ss.
Any suggestions or ideas?

[DeeZee]

Originally Posted by jasonmason

So I searched the archive but nothing really seems to sound just like this...

Yesterday on the loop my chain started slipping, but only when I'm on my middle ring up front and the midlle one in back. All the other gears are fine, and it only slips when i'm really torquing on it, hammering up stuff that I should be downshifting more for. Checked the rear der. adjustment, it's fine; no sticky links, no crap gumming up the cassette; teeth are worn in but not overly worn or bent.
I'm thinking maybe just that cog is wearing out on the cassette? I tend to abuse that one, torquing it quite a bit since i like to ride my geared bike like it's a ss.
Any suggestions or ideas?

drivetrain are you running....ie set-up?

[allison]

No, I didn't buy that Demo 8...

You should've bought the Demo 8.

[jasonmason]

Drivetrain is LX cranks, x-7 rear der, SRAM cassette, SRAM 991 chain (i think that's the number).

[DeeZee]

Originally Posted by jasonmason

Drivetrain is LX cranks, x-7 rear der, SRAM cassette, SRAM 991 chain (i think that's the number).

shimano there is an adjustment for the middle rings.

You may have a bent drl or drl hanger.

If the stuff is older it may look good but could be worn out. Without pics it is hard to say. If you have an extra cassette throw it on and see if the issue goes away

also there was an issue with XT cranks and the middle ring. Mine would pop-of the middle ring and wham! knee meet stem

[TURNERob]

It is probably your middle ring up front that is worn, the Shimano rings are pretty soft and wear easily. Best idea is to change the ring/cassette and chain at the same time assuming your derailleur hanger isn't bent. Have you laid it down lately on the drive side?

[ShinKen]

Originally Posted by TURNERob

It is probably your middle ring up front that is worn, the Shimano rings are pretty soft and wear easily. Best idea is to change the ring/cassette and chain at the same time assuming your derailleur hanger isn't bent. Have you laid it down lately on the drive side?

I was going to say the same!! middle ring may need to be replaced!! but hey if u're doing a nice overhaul than like ROb says. do em all @ the same time.

[jasonmason]

I don't think it's the hanger since i replaced it recently and haven't put the bike down on that side since then. How would the front ring be throwing off just one ring in the back?
The middle ring up front is kinda worn, could probably stand to be replaced. Thinking that I might not have explained this well - it's not slipping off the front ring but the middle (5) gear on the cassette.
What/where is the adjustment for the rings on shimano cranks? Haven't done that before...
Thanks for the help!

[DeeZee]

Originally Posted by jasonmason

I don't think it's the hanger since i replaced it recently and haven't put the bike down on that side since then. How would the front ring be throwing off just one ring in the back?
The middle ring up front is kinda worn, could probably stand to be replaced. Thinking that I might not have explained this well - it's not slipping off the front ring but the middle (5) gear on the cassette.
What/where is the adjustment for the rings on shimano cranks? Haven't done that before...
Thanks for the help!

middle rings in the cassette (rear drl)

but you have a Sram

how old is your drivetrain.....how many miles are on it?

You do not have an adjustment issue something is worn out. As posted if it it the cassette or front rings you need to replace the entire drivetrain

[jasonmason]

That pretty much goes along with what I've been thinking - nothing seems bent/broken or out of alignment, and the drivetrain's had at least 1000 miles on it. Guess it's off to get drivetrain parts...
Any suggestions for a good workhorse cassette/chain combo? Like I said I tend to get out of the saddle and hammer rather than gear down, so something that could take the torque would be best. Thanks again!

[DeeZee]

Originally Posted by jasonmason

That pretty much goes along with what I've been thinking - nothing seems bent/broken or out of alignment, and the drivetrain's had at least 1000 miles on it. Guess it's off to get drivetrain parts...
Any suggestions for a good workhorse cassette/chain combo? Like I said I tend to get out of the saddle and hammer rather than gear down, so something that could take the torque would be best. Thanks again!

the drivetrain's had at least 1000 miles on it

It is time my friend

Bring back 8 speed!!!!!

As far as a new combo it depends on how much kay'$h you want to spend. Nothing wrong with the XT rings, cassette and sram chain.

[CalEpic]

I'll jump on the front ring bandwagon too. I know it may feel like the rear, and it's only in the middle cogs but that is what happens.

I think the LX rings are steel so I'd replace with that. For the rear, whatever you can find a good deal on. I like Shiamno XT or SRAM PG990. SRAM chain w/ powerlink is the hot ticket imo.

C

[genusmtbkr5]

I also agree with Cal and DZ. As far as the Cassette/chain combo. I use a XT cassette 11-34, race face middle ring and a Sram PC970 chain. I save myself a few bucks and didn't go with the PC990 cause I've broken those too. BTW I like to hammer myself.

[J_Sims]

Originally Posted by allison

You should've bought the Demo 8.

What Demo 8

[Rob]

Take the cassette off and see if the cassette body on the hub is grooved.

I would get either an XT Cassette or the 990 because of the large body that the rings are mounted to as opposed to the cog and spacer approach by all lesser cassettes.

SRAM chains are cool for the powerlink but I've often got seized links.

[jasonmason]

Thanks for all the suggestions...yeah, I guess 1000 miles is more than enough to expect out of components!
Looks like i'll be running out to get these on before the ride sunday. Should make the climbing a bit easier having all my gears to use...

[tkblazer]

for a good deal on a cassette, nashbar is selling XT cassettes for $60. maybe have jenson do a price match on it so you get it sooner.

http://www.nashbar.com/profile.cfm?c...A%20Freewheels

i've used race face rings to replace the soft shimano ones, never had any problems with the RF rings

[thephat]

I would replace the chain and cass. Then, I would test out that middle ring. More likely than not, you will get grinding in the middle ring as the new chain sticks to the teeth of the worn ring. If this is the case, you will see the chain dancing a little. It is basically the beginnings of chain suck, we call it microsuck. If there is no skipping or sucking run that ring some more, otherwise replace it. We can price match $60 on a 2008 xt cass too fyi.