How important is a chain device/guide with a 9 speed MTB

davehmercer

I'm just in the process of building a 9 speed MTB and was wandering how important is it to have a BB mounted or seat tube mounted chain device/guide?

I am going to be using one of these chainsets if that helps?

http://www.ebay.co.uk/itm/120962208167

Thanks in advance

Dave

alan1985

I've just done the same, if your on the fairly smooth stuff (no rock gardens at speed) you'll be fine from what I've noticed so far with a long cage, my local is cyb so all was good until I hit pink heifer and big doug and I lost the chain 4 times and then otb and destroyed a new x9 shifter with 20 miles on the clock :-(
Went for the superstar xcr which does a great job if you take the time to set it up, if the chain does pop off It lands straight back on and that's with me running the original longer bolts,(used a few spacers to fill the gap which means the guide is higher than it should be), but I made up for the clearence difference by squeezing in a section of chain to stop it lifting (cable tie so it rebounds back down) hittin marin tomor for the first time so should be a good test ride :-O

The Rookie

You'll need a chain guide of some sort or it can just jump off the ring when shifting, you could use an N-gear jump stop inboard for example.

bennett_346

ideally some kind of guide that has a top and bottom element to it.

The Rookie

Top and bottom elements are not always needed, depending on usage, many people use a Bash and jump stop without issues, or the only issue being back pedaling which a top guide won't fix anyway.

bennett_346

Depends where you ride. If you ride here without a lower guide you'd be dropping the chain every 30 seconds, and they don't add much weight or cost.

The Rookie

'Here' meaning what sort of riding? I ride some fairly rough places and my twin ring has yet to loose the chain....

bennett_346

Are you saying i'm lying?

The Rookie

No, you said " If you ride here without a lower guide you'd be dropping the chain every 30 seconds" and I merely asked what sort of riding that meant, I'm not from Gateshead so I have no idea, nor would it meaningful to Dave if he doesn't know either.

Touchy aren't we?

cooldad

I think a duel is in order - strongly worded posts at dawn.

bennett_346

The .... at the end of your post suggests you are trying to say that what i said about my chain dropping is unlikely. It wouldnt be the first time you'd posted something like that where it was obvious what was inferred.

And no, i'm not touchy, i couldn't care less really.

The Rookie

No the .... means it is an open ended responce to allow you to reply with the detail I politely asked for....

bennett_346 wrote:

It wouldnt be the first time you'd posted something like that where it was obvious what was inferred.

And no, i'm not touchy

If you say so.....

As an example none of the riders in the Olympics that I saw had a lower guide and those rock gardens were pretty rough, so I'm trying to figure out what sort of riding definately needs a lower chain guide as you suggest, as it sounds quite lairy which may not be relevant to Dave anyway, plus as you've previously stated you'd never try a twin ring, unless you've seen one you don't actually know whether it would work or not making your assertion at the least an educated guess and not fact wouldn't it?

bennett_346

The Beginner wrote:

No the .... means it is an open ended responce to allow you to reply with the detail I politely asked for....

bennett_346 wrote:

It wouldnt be the first time you'd posted something like that where it was obvious what was inferred.

And no, i'm not touchy

If you say so.....

As an example none of the riders in the Olympics that I saw had a lower guide and those rock gardens were pretty rough, so I'm trying to figure out what sort of riding definitely needs a lower chain guide as you suggest, as it sounds quite lairy which may not be relevant to Dave anyway, plus as you've previously stated you'd never try a twin ring, unless you've seen one you don't actually know whether it would work or not making your assertion at the least an educated guess and not fact wouldn't it?

I wasn't being touchy, i was trying to avoid a big pointless argument over who has the rougher trails, which tends to happen with that kind of post when on this forum, so i asked up front instead of wasting my time bickering. More often than not i have refrained from asking and ended up in pointless back and forward "my trails are rougher than yours" arguments, and your track record for "debating" on this forum is well documented.

Secondly, i've never stated i'd not try a twin ring as i used to run one for two years up until last november where i got a new bike with a triple and changed to riding more long distance xc rides so any post i made regarding that was likely to be about not wanting to ride a double riding what i did at the time. I've since put a double and bash with chain device on this bike because my riding once again changed, to rough stuff.

I'm not sure how to explain the riding here but it's generally just very rooty with a lot of jumps so the chain just doesn't stay put unless you have a lower guide, and having seen the difference it has made since i've put it on i'd always reccomend them for double setups since they only weigh a few hundred grams.

Happy?

njee20

If you pedal backwards you're liable to lose your chain without a bottom guide. If you don't then you won't. It's more about style than terrain.

Personally I broke my (top only) guide, and absolutely couldn't fathom riding without any sort of guide (on a 1x10 set up), I'd lose the chain riding down a kerb. Completely impossible to make progress!

The Rookie

njee20 wrote:

If you pedal backwards you're liable to lose your chain without a bottom guide. If you don't then you won't. It's more about style than terrain.

Personally I broke my (top only) guide, and absolutely couldn't fathom riding without any sort of guide (on a 1x10 set up), I'd lose the chain riding down a kerb. Completely impossible to make progress!

Twin guide rings (one inner one outer) work fine backwards - but then they work identically as a bottom guide as well as a top one! Bennet346, you completely missed the point on that one by the way.

Agreed though, my 1x9 would often lose the chain on gearshifts around the middle of the cassette (extremities seemed OK) that was on my commuter with no real bumps or kerbs.

bennett_346

What's a twin guide ring? Edit: i assume you mean twin ring guide oops.

Bouncing around drops the chain off the bottom of the chainring on rough rides without a lower guide of some sort, i find, so back pedalling isn't the main reason i advocate lower guides.

The Rookie

Yep, twin guide rings.....

Bouncing may drop the chain off the bottom, but surely as the cranks turn the bit at the top becomes the bit at the bottom?

I often ride down some quite violent city centre steps (childish I know - but fun!) and never lost the chain....that is some fairly extreme inputs.

njee20

Bouncing around drops the chain off the bottom of the chainring on rough rides without a lower guide of some sort, i find, so back pedalling isn't the main reason i advocate lower guides.

Yep, as above, if you then pedal backwards you lose the chain. If you pedal forwards you don't. Never happened to me.

davehmercer

Thanks for all the replies chaps!

I will be using the bike mainly for commuting but my route can and more than likely will take in a few trails and bridle paths etc, but will probably take the bike to places like leith hill for a bit of single track etc as its local to me.

I was planning on ordering one of these, would it be suitable for my type of riding?

http://superstar.tibolts.co.uk/product_ ... cts_id=475

njee20

I've just fitted one of those. Previously had a home made one before they did seat tube mount, my bodge lasted 2 years, so not too bad. Only dropped the chain once too, same local riding as you. The grub screw in the SS one is a bit iffy, but otherwise seems alright.

The Rookie

My commuter uses an old Sora front mech which I've removed all the lever and spring gubbins from and it just locks off on the pivot bolts, has worked fine for nearly 3000miles now!

Northwind

I've got 2 single ring bikes with top guides... The one with a clutch mech works, the one with a standard mech doesn't really. Nothing to do with back pedalling, it drops the chain as and when it sees fit. Better chainguide might sort it.

The Rookie

Sounds like it's set up wrong, is it dropped down over the ring (lower than it could be used as a front mech)?

Northwind

Dropped as far as is possible, yup (and set up the same as my other one which works perfectly;) )

The Rookie

Strange, I know a fair few using one with no issues, after all where can the chain go?