Thread: 1x9 drive train issues

so heres the deal, this winter i built up a 1x9 banshee scirocco as an all mountain rig for here in minnesota. i built it as something i can hit up the pump track with, or local down hill (for as small as it is) and all around single track use.

because of that i ran a sram 11-34 9spd in the rear w/ a 36tooth up front. im currently running x9 shifter and rear derilur. the issue im running into is that i cant seem to use the full range of gears because of drive line issues. with the chain in the 34cog, it just wants to hop off.

i was possibly thinking about switching to a medium cage deraliur from my long cage, and putting on a road cassette instead of the mountain cassette. some quick mental math told me that with an 11-22 spread and the 36 on front i would still have plenty of gears for climbing.

what im wondering is would this be more appropriate to run the road cassette 1x9 instead of the mountain cassette, and should i switch to a short cage instead of a medium cage deralur. thanks for your input.

if you go to my blog, there are build specs for and photos of my drive line.

is the drive line straight on the 5th rear cog (middle?) if not spacer out the chain ring, or the BB more.

If the chain tension is right (for that gear combo) ring, cassette, and derailer size shouldn't matter, but maybe try one less chain link?

does the chain "hop off" the front ring? or the rear?
if rear check the limit screws
if front might be chain line (see above) if the chain line is right, maybe move the rings in a bit anyways to see if that is better.

Dude,

Bashguard and one of THESE THINGS= problem solved. If you want something a little blingier, or don't want to run a bashring (though I think you're making a big mistake ) you can go for the Rohloff version. If you are still dropping your chain in rough stuff, just get a proper chainguide. In fact I have a 40-36 e13 STS, that I would like to replace with a smaller version (little outsized for the 32T I'm running). If you are interested, PM me.

Oh, and switching to a road cassette won't help your drive line issues, it will just make you hate life when climbing (I'm a little confused though, you did say "climbing" in Minnesota, right? )

Oh and check the stuff that Mtnlion said too.

mtlion is right, your chain line should be pretty much straight in your middle cog. If yes then we are pretty sure it's not a chain line issue.

From what you describe, I am assuming your chain might be too short. I am assuming this because you are saying your chain is hopping off the largest cog (you are not saying it is hopping off the chain ring or this is happening during rough riding).

Break your chain, and then wrap it around the chain ring and largest (34) cog but do not run it thru the derailleur. Pull your chain tight and add two links = your ideal chain length.

Cage size on derailleur has nothing at all to do with anything in a 1x9 set up, although with that set up you can use a short cage. Anything longer is not required but it will have no adverse effects except shifting may not quite be as crisp. Personally I don't think I can tell a difference.

So if your chain line is good and your chain is not too short, your low limiter screw needs to be wound out a touch or your hanger is bent.

Oh, and no, 11-22 out back is nuts unless, of course, your hills are flat. 36-22 you'll be hiking, not climbing.

On my 1 x 8 I have either a 26 or 32 tooth chainring (depending on where I'm riding) and in the rear a 12-25 cass. with a short cage Suntour something Pro from the mid '80's. '98 Deore XT crank, 113mm bb, chainring in the middle spaced inboard an additional 3mm. No drop issues in either direction.

if you figure out the chainline maybe one of these will help http://www.velonews.com/article/9365...-1x-chainguide

a short cage would help, and as short of a chain length as possible would help, i don't think a smaller cassette would matter though.

Originally Posted by marshalolson

a short cage would help, and as short of a chain length as possible would help, i don't think a smaller cassette would matter though.

I've been working with chain length recently too. Did the recommended measuring procedures, but damn if the chain doesn't look to short (looking at the derailleur cage angle) when in 1st gear. How do you really know when the chain's too short?

Originally Posted by oftpiste

I've been working with chain length recently too. Did the recommended measuring procedures, but damn if the chain doesn't look to short (looking at the derailleur cage angle) when in 1st gear. How do you really know when the chain's too short?

Copied from my post above:

"Break your chain, and then wrap it around the largest chain ring and largest cog but do not run it thru the derailleur. Pull your chain tight and add two links = your ideal chain length." With a dually you'll want the rear suspension fully compressed (remove one shock pivot bolt and disengage your shock and let collapse {while supported of course}).

if its a 1x9 on a hardtail w/ a short cage you can run front->big + 1 link.

i personally like running road rear derailleurs on 1x9's.

hmm, ill look into these suggestions. the der hanger is brand new, the chain line is straight in the middle cog, so maybe its simply too long of a chain.

Originally Posted by marshalolson

i personally like running road rear derailleurs on 1x9's.

Ditto. As long as they are short cage.