I ditched the 2x9 drive train on my 29'er to go with a 1x9 set up (32t front & 12-36t rear). The front ring is a Raceface un-ramped one. The guide is an M-part one.
It's be fine until the last ride out - it was freezing cold and the ground was solid to the point where ruts were solid lumps - the chain must've come off the front ring around 10 times in 2 hours.
The set up is as pictured below.
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Does it look right for positioning over the ring?
It's only happened in these freezing conditions, could it be down to the mech getting a bit cold and not keeping tension in the chain allowing it to unship from the ring?
It could be because its not a proper chain guide and you were riding on very rough ground. How many downhill riders do you see using one of those guides? None?
Good answer if not quite the one I'm looking for 😉
Guess I might save for a proper one then
What's wrong with that guide? No need for a full on DH guide for XC riding.
If it's never been a problem before and then was that bad yesterday (assuming you've ridden it in anger before on similar terrain) then something's awry, hard to tell from the pic, but it looks alright. How were you losing the chain? Over the front or back of the ring?
If you were back-pedalling at all you would lose it on account of having no bottom roller.
Add a bottom roller and you'll be sweet as a nut I'd say.
njee - I've not ridden it on solid rough ground like this before, generally softer woodsy terrain.
The chain came off the front of the ring.
I can only think that the chain/mech was a bit frozen 😳
I've tried to get one of those guides set up on a 32t ring, but they foul on the chainring bolts, so don't really cover enough of the chain & rin to be effective. Larger rings work better, as do other brands of chainguide.
george - what alternative would you suggest?
Jump-stop and a bash, job done...Or a Paul's chainkeeper if you prefer the aesthetics.
Will the chain not come off the top of the ring if you use one of those?
You talking to me? ❓
yup
Nope, the bash will keep it from falling off outboard and the jump stop will stop it dropping inboard. If you are still dropping the chain during xc riding with that set-up you've got chain tension issues. 😉
HTH
Hmm, chain tension issues.
So on a single ring set-up you'd go for:
Chain round ring & biggest cog at the back and then add 2 links as per a normal set up on a HT
Yep, as a rough guide, then I took out another link IIRC so's the cage was sitting at a nice 45 deg angle whilst on biggest sprocket and the tension was perfect.
Never dropped the chain with that set-up and gets my vote everytime. Your's and others mileage may vary but a DH chain device will look gopping on a 29er HT imo 😀
is that a chumba HX2 ??
i run similar set up, but a 'tight' chain, no problem so far.
Cheers guys.
Turns out the chain was 3 links too long 😳
I'll give it a go tonight and look at getting one of those jump-stop thingies.
Goot - it sure is, well recognised
FWIW i had the same problem with my superstar one this summer... solved by (in order of how much it actually helped...);
a bottom roller
'modifying' the inside dimensions of the guide to make it narrower in the right places, with zip ties
not pedalling backwards
bottom roller was a revelation - not one problem after i fitted it.
Do you mean came off the ring and got snagged up in the guide?
Using a bashguard may help but a pauls chainkeeper is exactly the same as what you have just more expensive.
Otherwise a light DH chainguide. Top end dh guides will cost up to 10x as much, weigh almost three times as much but your chain won't be going anywhere.
Freewheel not being free enough? Blooming things are very prone to this issue in freezing conditions. Make sure there is no free water in there. Replace any grease with oil.
Can it be lowered any more? That would stop it jumping off the top I think.
Nope, can't go any lower due to it fouling the chain ring bolts.
2.5hrs tonite and the chain didn't come off, must've been the long chain
steve - the E13/MRP ones are shaped a bit better for a 32t ring. (you'll pay three times the price for that though)