Chain coming off

sandy771

I am looking for a way of stopping the chain coming off my bike on some of the more bumpy downhills I have been doing.

Bike is a 2012 trance x3 with a pressfit bottom bracket and is 3x10.

Happy to go to 2x10

What are my options?

Chunkers1980

A device or clutch mech

mystery h

check your chain length, even try to keep the chain tight (big cog + big cog) when descending

other ways to explore are chain devices

sandy771

Thanks

Did the big cog big cog last night and things seemed better but on one occasion my chain did come off (forgot and was on middle cog) and I am getting a bit pissed off with it.

Not really too bothered about losing the front bigun as it is rarely used.

Can a chain guide be fitted on a pressfit bottom bracket?

mrmonkfinger

mystery h wrote:

other ways to explore are chain devices

quick google says no ISCG tabs

t0pc4t

isn't there that bionicon chain device that will attach to the swingarm?

benpinnick

The SLX clutch mech will be out soon. That will be a good option for not too much money, assuming you're ten speed already.

Chunkers1980

Will clutch mech of the shinano variety be available in 9 speed?

benpinnick

Doubt it. Another way to make you go 10 speed Im afraid.

cat_with_no_tail

t0pc4t wrote:

isn't there that bionicon chain device that will attach to the swingarm?

>>Yes<<, and it works very well. Excellent option for those running a triple.

sandy771

The only place that seems to have the bionicon for sale is bike-mailorder.de - has anyone dealt with this company, are they any good?

cooldad

mystery h wrote:

check your chain length, even try to keep the chain tight (big cog + big cog) when descending

other ways to explore are chain devices

Tightish, yes, big/big - I wouldn't recommend

andymc06

+1 for the Bionicon V2

Try German ebay.........

Anonymous

cooldad wrote:

Tightish, yes, big/big - I wouldn't recommend

Interestingly SRAM say 2x10 cross-chaining = OK.

Anyway, chain drop can be down many issues and before rushing to get a chain device, check the chain length/wear, check tension in the rear mech and/or change mech (possibly fiddle with the B screw which may help with a slack chain), is the chain the right length for the set up? There's no guarantee it will be supplied with the ideal length or tuned right for you.

Also, where's it dropping? Off the crank (off big or small), or dropping from one ring to another? If the latter, check the indexing is right as it could be the cage is just on the edge of pushing the chain down a ring and a simple adjustment will fix it. If it keeps falling off crank on the big ring, maybe a bash guard will help.

With full suspension bikes there are added complications as depending on the suspension design you get a degree of movement affects chain tension.

As for changing to 2x10, won't solve the problem, though 2x10 is a nice substitute for 3x9. However in doing it you can change to a medium cage mech which may help with chain tension. That said, I'm getting chain drop with my 2x10 and there's much discussion on the web about this being a particular issue with SRAM's 2x10 kit, especially with the X series 10 speed mechs. My attempted solution is going to be a chain device of some sort though I do think it's slacked off over time so maybe the (bloody expensive X0 !) mech is dodgy.

cooldad

deadkenny wrote:

cooldad wrote:

Tightish, yes, big/big - I wouldn't recommend

Interestingly SRAM say 2x10 cross-chaining = OK.

Except he's running 3x10. Still unnecessary, even with 2x10.

garylythgoe

I've been struggling with this recently, and after dropping my bike off at my LBS yesterday, asking for this to be investigated (I'm 2x9 with Shimano XT stuff). My chain is/was excessively worn, and the rear mech sprocket arrangement was completely missing any teeth, so the chain was slack and slipping! Pig to ride!

Well worth checking out mate, they put a clever tool on my chain to assess its wear level.

cooldad

garylythgoe wrote:

I've been struggling with this recently, and after dropping my bike off at my LBS yesterday, asking for this to be investigated (I'm 2x9 with Shimano XT stuff). My chain is/was excessively worn, and the rear mech sprocket arrangement was completely missing any teeth, so the chain was slack and slipping! Pig to ride!

Well worth checking out mate, they put a clever tool on my chain to assess its wear level.

? You had no teeth on the cassette?

sandy771

Thanks all

Bike is pretty new so chain wear is fine although i did have it serviced and checked the other day as we are off to wales for a weekend in a fortnight. Gears were set up at service and are now v smooth but I still lose it (and the chain) occasionally. Chain length is also good as we discussed removing a link or two as an option.

Have just ordered a bionicon c-guide to see if that helps - unfortunately only available in pink at the mo !!

Anonymous

garylythgoe wrote:

they put a clever tool on my chain to assess its wear level.

Probably this http://www.chainreactioncycles.com/Mode ... tedKingdom

Though curious as to why Park Tools have changed it and now encourage you to replace chain *and* cassette at .75% wear instead of 1%. Do they have some deal with cassette manufacturers?

Or you can use a ruler http://sheldonbrown.com/chains.html#wear

garylythgoe

Forgive my n00bness, I'm a car man who loves riding bikes :oops:

The wheel on the bottom of the mech in this pic, no idea what its called:



It was 'round' and had no teeth! :shock:

bennett_346

Jockey wheel. I've ran them with no teeth for years, doesn't make any difference!

garylythgoe

Oh, well either way, I dropped my bike in a for full going over (Cube AMS 125 XT) and I'm hoping its going to come back feeling better than ever 8) 8)

Had a few bits done too

Anonymous

Jockey wheels wear down more than everything else, and I believe are designed to. Never quite sure if it has much effect running them worn, but once they become like throwing stars I replace them. Cheap and simple to do. Though this time round I went for bling instead (KCNC). Not sure if they're that good an idea as suspect they're harder wearing and the chain may wear instead. Or not. Bonus though is the KCNC are really nice to clean. Big open spokes for mud to fall through and ceramic bearings. Usually my jockey wheels clog up really bad with mud and the bearings in them grind away.

sandy771

Just had my first run out with the bionicon chain device - alhough it was a relatively gentle run therre was a couple of good descents and it seems to a have done the job. Very quiet, i.e. effectively silent and didnt seem to affect shifting at all.

The only problem with it is that they only had it in pink !!