[Closed] What is a clutched rear mech

Basically the mech includes an inhibitor you can activate which stops it working properly...............

It may also stop some of the chain slap.

Chicken/Egg. Egg/Chicken.

That's weird billy, mine shifts fine and eliminates all chain slap. You know you're not supposed to install it with a hammer right?

Marketing malarky........

Yeah sorry Billy I think my clutch rear mech is great, works a treat and no chain slap, totally reliable shifting. What's not to like?

It stops the mech from having full movement which results in less chain slap. The 'technology' has always been there but marketing dictates that it is very new and therefore more expensive...

Does that mean it has a less springy spring?? 😆

You have to be a real hardcore hater not to like clutch mechs.

nobody seems to have answered this question, i would like to know too.

what is a clutch mech? - how is is different from a normal mech?

it has a clutch.

Weh! Evening collective ar*ey mode..

It has a clutch that stops the rear mech jockey wheel cage from swinging back and too on its spring when you go over the rough stuff. This significantly reduces chain slap and prevents the chain from jumping off the chain ring. The clutch allows the jockey wheel cage to move forward and back for shifting, but will effectively lock it in place once shifted.

Makes you wonde why it has taken them so long to introduce them really.

^^ thanks

(having ridden one, I wouldn't buy one without)

I hadn't realised how gloriously quiet they make your bike until a mate came out on his full sus instead of his singlespeed and was clattering along behind me... 😉

As I understand it it applies more friction and slows down the fore-aft movement of the derailleur cage so that when you hit a bump, instead of the mech deflecting and creating chain slack, the tension stays constant. It may do something clever like reduce this friction when you're shifting but I'm going to be honest and say that I haven't actually played with one

I hadn't realised how gloriously quiet they make your bike until a mate came out on his full sus instead of his singlespeed and was clattering along behind me...

Here's a good article on the insides:
http://www.pinkbike.com/news/Tech-Tuesday-Inside-Shimanos-Shadow-Plus-Mech-and-How-To-Adjust-.html

I was riding some fast rocky descents last night and I really noticed the silence. Not noticeably stiffer to shift but no chain slap and much less likely to drop the chain. Brilliant.

Does it make a noticeable difference to chain slap on a hardtail, or is it really only beneficial on a full susser?

Does it make a noticeable difference to chain slap on a hardtail

Better described by those that beat me to it but I'll summarize with the fact that I'll never buy a regular mech again. (and that's me using a Zee mech in a ghetto SRAM/Shimano 1x9 setup)

While it's no doubt something new to sell us, you'd have to be the kind of person that can't see the point of dropper posts to think it wasn't a great idea.

What is a clutched rear mech?

The best thing ever!* 😀

*I may have also said that about fatbikes, wide bars, dropper seatposts, ergon grips, hydraulic disc brakes, full suspension bikes, clipless pedals, suspension forks, flat narrow handlebars, bar ends, Shimano CS-M900 8 speed XTR cassettes, Suntour XC Pro 8 speed thumbshifters... 😳

It's a one-way clutch, meaning the spring can move the jockey wheel back to take up chain slack just as easily as on a normal mech, but then requires extra force for the jockey wheel to move forwards again, reducing chain flap, and increasing the force needed to move onto larger gears.

I've never tried one, but unlike most recent bike "innovations", it strikes me as a neat solution to a real world problem.

[i]you'd have to be the kind of person that can't see the point of dropper posts to think it wasn't a great idea. [/i]

[puts hand up]

Love my clutch mech, it's a fantastic bit of kit, don't need a dropper post...

How's that?

Are they available in 9speed ?
I currently have a Medium cage X0, so would like something of a similar spec, but not ready to change every thing over to 10 speed

[puts hand up]

Love my clutch mech, it's a fantastic bit of kit, don't need a dropper post...

How's that?

I didn't suggest it couldn't work that way around 😉

Are they available in 9speed ?
I currently have a Medium cage X0, so would like something of a similar spec, but not ready to change every thing over to 10 speed

You're in luck as you're using SRAM shifters you can just buy the Shimano 10 speed mech to suit you budget and fit it. Only modification required to work (well) is a 5mm spacer under the cable. See [url= http://singletrackmag.com/forum/topic/9-speed-sram-shifter-with-a-shimano-10-speed-clutch-rear-mech-will-it-work ]THIS[/url] thread.

I've done it with X9 shifter, Zee mech and 9 speed XTR casstte and chain and it works faultlessly.

Thats great thanks
I have XO shifters and a Lathe so I`ll make a spacer up
Cheers
Dom

The 'technology' has always been there but marketing dictates that it is very new and therefore more expensive...

Well yes clutch technology has existed for a long time, but no one has applied it to a mech, so it [i]is [/i]new, and it's barely any more expensive. Sarcasm fail, try again.

Someone in a bike shop told me that you can't (or maybe not supposed to) change gear when the clutch is activated. Surely that's not right...is it..? He said that the idea was to switch it on at the start of a descent and it would stop the chain slapping about, but then you'd be locked into that one gear until you switched it off.

That someone in a bike shop doesnt know what he's talking about.

No, that's bollocks. The only reason to release it is to make it easier to get the wheel out.

Love my clutch mech! Noticeably quieter than my old one.

Is it stiff enough such that you wouldn't need a chain device for 1x10, say?

PDW has it right - it is ratcheted so only works in one direction. It also has adjustable tension if you don't like the extra stiffness it adds to gear changes.

In fact the only downside I can see is that because they've only been around a while, we don't really know their reliability, or how long it takes for the clutch to wear and become less effective.

Meanwhile, here's what it looks like...

[img] [/img]

No, that's bollocks. The only reason to release it is to make it easier to get the wheel out.

Not only is it bollocks, it won't work with SRAM Type II as I gather the clutch activates automatically if you ride off with it disengaged.

Is it stiff enough such that you wouldn't need a chain device for 1x10, say?

For XC use, the bloke in my LBS reckons so. I am prepared to give it a try to find out, but (without one of those wide/narrow toothed chainrings) I have a sneaking suspicion I'll need a top guide at least.

Gary- in my experience, yes. I've got a 1x10 on my chumba using a medium cage XT (above) and the chain hasn't dropped yet.. Riding has been singletrack and XC so nothing adventurous (yet).

Thanks - I thought it sounded a bit barmy!

it's barely any more expensive. Sarcasm fail, try again.

Nope, not sarcasm...fact...I said it was more expensive...and you confirmed it...even 'barely' is more...

Personally I've never had a problem with a chain dropping off due to going over rough stuff...admittedly I suspect I'm far less capable than most on this forum, but I've yet to ever drop a chain outside over/under shifting and not getting it right for whatever reason...I've never ridden along and managed to get my chain to come off over rough stuff. I can't see the benefit of it (and I've yet to ride with anyone who has a chain dropping issue). My last chain drop was a good few years ago (due to skelping a mech to move it on the frame)...it just isn't something I experience (or have seen happen to anyone else) - admittedly the last 2 years or so have been largely rides on my own so that isn't going to help if this has suddenly just arrived on the scene...

The marketing is looking for something else to big up and this is nice - I think the concept is excellent, but I also don't think it is needed.

I'm just waiting on my dropper coming back from warranty work...now that is a definite improvement on the faff of saddle height when you are anal about it as I am!

It's good to ask the question OP. Quite embarrassing to demo a bike (with clutch) and then struggle to fit back wheel. That is until nice fellow cyclist puts you out of your misery and explains what the little black button is for!!!!

Is the type 2 as good as the shimano version. Only I have an XT clutch mech on one bike which works really well. I have an X9 type 2 on another bike and it doesn't seem to have anyway near the same effect. Is it possibly not working properly?

DickB - do you use 1x10 or are you on a double or triple chainset?

I think they're more useful/important on 1x10 set ups, where if the chain moves at the front, you don't have a front mech to lift it back on but often just end up with a dropped/jammed chain. So the clutch mech will halp keep better tension along the bottom run of the chain and reduce the likelihood of the chain coming off.

I'm still using a top guide though for sure.

I have a SRAM X9 clutched mech on a 2x10 full suss Trance 29er and a Shimano SLX clutched on a 1x10 Hardtail Lurcher. Both are excellent and besides the tiny extra cost over the (IMHO now defunct) non-clutch mechs there seems to be no downside. Riding with the clutches engaged all the time on Mendips and Cwmcarn XCs and downhills. I have dropped chains without clutch mechs and don't us any other type of chain device. Now a thing of the past.

Don't think you can get a 9speed clutched mech which is a pain as you need to get the chain and cassette to upgrade to 10 rather than keep you 9s stuff.

Andy

Not 100% true, im now running 9 speed with a 10 speed SLX clutched mech. Thanks to this forum, all it took was a 6mm spacer under the cable and it works perfectly.

Long term how durable is the clutch mechanism? considering that its subjected to all the loads that were previously applied to a spring.

Eventually it must start to go "a bit baggy"? How are the earlier efforts faring?

Eventually it must start to go "a bit baggy"? How are the earlier efforts faring?

At least on the Shimano ones you can adjust the clutch tension. Some people have said you should do that after a couple of months, I didn't really find it necessary. But the option is there.

Or do you mean the clutch pivot itself could becomes baggy side to side? Possibly, I guess. I've only had mine 6 months and it's still very much nice and tight.

Imagine swapping the sound of your mech slapping about for the sound of your tyre rasping against the dirt. Imagine being able to hear the changes in terrain as you're ripping down your favourite descent. It's beautiful. Screw your CTD / Kashima koating / 27.5" wheels, those things are bullshit marketing innovations. Clutch mechs however are fantastic.

Love mine - and as it's just a sprag bearing with a band brake around it, it's easily adjustable and should last pretty well I'd have thought. They seem fairly well sealed, unlike the jockey wheel bearings... 🙂

They're great but not magic unless my 2 aren't set up properly.

Slap against chainstay is eliminated, slap against the front mech cage is still there on rough stuff. Don't see how tensioning the bottom run of the chain can stop the top run of the chain moving from side to side.

As a result bumpy descents still generate clattering 🙁

There isn't much you can do about the front mech noise, as its generally side to side chain slap that causes it.

The only real solution is to man up and ditch the front mech. You will still get some chain noise, and slap into the spokes etc, but generally it's a lot quieter.

As an early adopter, I've had a Saint clutch mech over 12 months now, and its looking a bit worse for wear, but there has been a lot of riding, racing DH & enduro's, 3 weeks in the Alps including the Mega & a minging winter. All cosmetic though. I took it apart and get it a clean & regrease inside, but otherwise no issues at all.

I have had a couple for a while and they do seem to get through jockey wheel bearings more quickly. Not surprising with the increased loads/tension the jockey wheels are under.
Still well worth it. Simple/cheap real world improvement.

2x10 and before that 3x9; 3x8; 3x7 and started with 2x5...

Single chainring with a mech does make more sense now you have mentioned it, but again, the bikes I've seen with a single up front (a grand total of about 3), never lost the chain...but I suspect they had some sort of chain device.