So, I’ve taken advantage of this poor weather to winterise the bike and went for a 1×9 set-up. On the front I have a standard XT crank with a 32 ring in the middle ring position. The HT2 BB has one spacer on the drive side (no chain guide or mech fitted)

Chain line looks spot on but when I go into the lowest gear on the rear (32) the chain comes off on the inside. Is there a way round this or do I need to fork out for a chain guide (1.X MRP) which I can’t afford.

Also: where can you by the correct chain bolts for the a single chain ring. I’ve totally botched something meantime. Cheers

Alek

Alek – what BB shell width?

Not sure this helps but I converted to 1×10 just keeping middle up front and had no problems.

Perhaps you bb is spaced wrong? Dunno

Is it not just to do with the limit screws putting the derailleur/chain too far over toward the spokes?

I tried just what you have.

You’ll need shorter chainring bolts. IIRC Charlie the Bike Monger does them.

Also IME you will need either a chain guide (ala Superstar £16 one) or a very tight chain to stop it jumping off at the first sign of a bump. Or you could maybe try a chainring with taller teeth (I havent tried that).

Cheaper alternative to the MRP device: http://superstar.tibolts.co.uk/product_info.php?products_id=362

I flipped the chainring over as mine wasn’t symmetrical and it made the chain line better.
I would thoroughly advise getting a guide of some description, at least to stop you losing the chain, you can use an old mech or bodge something together without shelling out for one

if you want a reliable 1 x 9 setup you need a chain device, its really that simple 😉

I’d recommend E13’s LG1 device, run these on both my mountain bikes running 1 x 9 setups and have never dropped a chain

1×9 is my preferred set-up and I have encountered the same. Chainring was too far out. The other one which will want to rattle your chain off the front when on 32 is a one not tight enough.

Use an unramped chainring makes a huge difference

TJ is correct, ramped chainrings are made to aid shifting, which is what your XT ring is doing, and inramped ring will be loads better, i’m using a Renthal and have no issues with losing the chain

1×9 run today for first time with unramped Renthal chainring. Hopeless – lost chain 5 times. I think that it was when I back-pedaled. So from my perspective a chain device seems sensible.

N-Gear Jump Stop. I’ve been using one for the last 6 years with no chain drops, even when using a ramped chainrings. An unramped ‘ring will also help. I also run both spacers on the non-driveside to get the chainline spot on when the chain’s on the middle sprocket.

One way or the other I think you’ll have to spend money. As said above the problem is using chain rings that are designed to aid shifting. It’s not so much the ramps as the gates in the ring, the teeth are probably not as tall as on a single specific chainring. So first port of call is a single speed chain ring. You may still want a chain device too – such as the Superstar one.

Seems like 1xX is the new SS. Not knocking it, I’d be happy to have a go myself.

slight hijack, but on my 1×10 set up (middle ring, unramped, chainguide) when i backpedal the chain drops off the 36 and goes lower down the block. not been able to ride it yet (alps is a bit snowy!), so just a garage test. limit and b tension are all set up as i’d usually have them.

I use SLX middle chainring, bashguard and NGear jump stop, never drop the chain.

Kev

1×9 run today for first time with unramped Renthal chainring. Hopeless – lost chain 5 times. I think that it was when I back-pedaled. So from my perspective a chain device seems sensible.

are you running a shorter chain than for a 3 x 9 set up? just to give the rear mech more tension?

Check out this link …

http://forums.mtbr.com/showthread.php?t=256673

It’s something I’m trying at the moment. Removed 44t outer and 22t inner rings, replaced the 33t middle with a 36t MPR ring, and bought an e13 bash to stop the chain slipping outwards.

As willyj suggested, also bought an n-gear jump stop to stop the chain slipping inwards. I’ve only recently ordered the parts, so can’t comment on how they work, but reviews of the n-gear jump stop are good, and it only costs a tenner.

Im running bash on outer, 32T ramped Deore ring and N Gear jump stop. Using a short cage MTB rear mech and a fairly tight chain. Not a problem since i fitted it a few months back.

I reduced the chain to suit but could possibly lose another link.
The chain ring is ramped so might need to look at that too.

Bonesetter: its a HT2 and I just removed the central plastic connecting piece and run a spacer each side.

Sounds like a chain device is needed and the superstar looks to fit the bill. Cheers for the advice and its reasuring to know its not just me with a few teething issues.

Why do chains come off so easily now? .I never lost the chain on a single ring road bike as a kid.I assume it’s the design of chains and sprocket teeth now

Ek Have a word with Ewan, he is running 1×9 this winter. He has kept the front mech on as a chainguide and he hasn’t had any problems so far 😉

Will do Gord……….

Why do chains come off so easily now? .I never lost the chain on a single ring road bike as a kid

“road bike”

There’s your answer.

N-gear jump stop is £12 posted (or thereabouts) from eBay. That works fine for me and I’m too tight to buy a new non-ramped chainring.

Renthal + N-Stop by rOcKeTdOgUk, on Flickr

my n-stop was £9.99 from billy’s bike store http://www.billys.co.uk/english/group.php?prod=chng-js
although i don’t think i actually need it as i’m not running a bash guard and the chain hasn’t come off once

are you running a shorter chain than for a 3 x 9 set up? just to give the rear mech more tension?

Good point – I had not shortened it as had chain device on order and wanted to set the ideal length once that was fitted.

With these 1×9 set-ups you really need to go as short on chain length as possible
Check out this pic. The chain is not on the 34 either

No drop devise. Chain NEVER drops

Try a short cage rear mech too….. Worked for me.