Xt rear derailleur questions

[Big Bike Basher]

I have an xt rear mech. It has like a leaver on it that seems to lock it off.
Why is this on here please?

 

[Bones]

It's the clutch. Up is on
The purpose of it is to keep tension on the chain. it is adjustable and it does need a little TLC every now and then.

 

[Big Bike Basher]

It's the clutch. Up is on
The purpose of it is to keep tension on the chain. it is adjustable and it does need a little TLC every now and then.

Why have they fitted a clutch?
At what point does it slip or does the chain snap?
It seems to keep the tension way too tight as when I change gear it's brutal on the shift ...
I don't see how it is any help

 

[Bones]

It stops the chain from jumping off the chain ring when you are rattling down a bumpy decent.
Flick it down when removing the wheel.
If it starts sticking you will notice the chain is saggy.
Shimano have the online PDF of the mech and it gives you the service info.

 

[Big Bike Basher]

It stops the chain from jumping off the chain ring when you are rattling down a bumpy decent.
Flick it down when removing the wheel.
If it starts sticking you will notice the chain is saggy.
Shimano have the online PDF of the mech and it gives you the service info.

Hmmmm.
Ok
Never had issues before with chain jumping off on bumpy descents.
Is it because the mech is so much longer to accommodate the 12 speed mahoosive cassette?

 

[Bones]

It's above my pay grade to question why

 

[Big Bike Basher]

It's above my pay grade to question why

Oki dokey.
I'm tempted to fit a smaller range cassette and shorter cage standard mech.
Thanks

 

[Montana St Alum]

Shimano came out with the clutch at least 10 years ago. As Bones mentioned, you can service the clutch to make it work as designed. Sometimes dirt and grit get into the mechanism and prevents it from working optimally. You can also adjust the spring tension on it. You shouldn't see a substantive difference in shifting difficulty with it on Vs. off. OTOH, I have the clutch on my wife's 1x11 set pretty light on resistance just to make it a tiny bit easier.

It does help with chain retention, though I don't drop chains in the rough when I forget to engage it. Maybe my "rough" just isn't that "rough".

 

[Big Bike Basher]

Shimano came out with the clutch at least 10 years ago. As Bones mentioned, you can service the clutch to make it work as designed. Sometimes dirt and grit get into the mechanism and prevents it from working optimally. You can also adjust the spring tension on it. You shouldn't see a substantive difference in shifting difficulty with it on Vs. off. OTOH, I have the clutch on my wife's 1x11 set pretty light on resistance just to make it a tiny bit easier.

It does help with chain retention, though I don't drop chains in the rough when I forget to engage it. Maybe my "rough" just isn't that "rough".

Oh it's rough where I ride.
Maybe Shimano have just made it a gimmick as I really don't see any benefits.
I will change the set up.
I'm going back to 9 speed and standard mech. This giant 12 speed cassette is ridiculous along with the mech...
Besides I think the 9spd chain and cassette will be stronger and smoother on changes.

 

[cozzy]

Buy linkglide if changing. Designed for ebikes.

 

[Big Bike Basher]

Buy linkglide if changing. Designed for ebikes.

Don't really see how being an evbike makes much difference.
A 9 SPD chain will be strong enough

 

[Zimmerframe]

There's lots of Gimmicks. The Clutch isn't one of them. Most derailleur's have them.

Personally, if I ride a bike without a clutch the chain WILL come off the chainring - even if you have a chain guide.

If you have a clutch and a narrow wide chainring, quite often you can get away without having a chain guide as the clutch provides sufficient tension to keep the chain on.

Yes, 12 speed cassettes are on the whole unnecessary on an EMTB, unless you like to ride in Eco on the steeps.

If you're changes aren't smooth, this isn't the clutch. Either your derailleur needs adjusting (B Screw) or you're not easing off correctly as you make your change - so you're making full power changes and will just destroy your cassette in a much shorter time than if you make smooth changes.

If you're looking for advice, stick with a derailleur with a clutch even if you do decide to drop to 9 or 10 speed.

 

[Zimmerframe]

Don't really see how being an evbike makes much difference.
A 9 SPD chain will be strong enough

Are you here to learn anything and take people's advice and research what they're telling you, or just blunder through ?

Linkglide is primarily the cassette type. It changes gear with slightly more longevity when under load due to the teeth and ramp designs.

A 9,10,11,12 speed chain are all strong enough, but you can still snap any of them with crap gear changes - especially with the extra torque from the motor combined with the riders power.

 

[Big Bike Basher]

Are you here to learn anything and take people's advice and research what they're telling you, or just blunder through ?

Linkglide is primarily the cassette type. It changes gear with slightly more longevity when under load due to the teeth and ramp designs.

A 9,10,11,12 speed chain are all strong enough, but you can still snap any of them with crap gear changes - especially with the extra torque from the motor combined with the riders power.

Well don't make crap gear changes then,learn to ride
My question was why the clutch on the mech when it's unnecessary.
Huge 12 speed cassette is also unnecessary so I'm going to change it for a sensible 9 speed cassette ratio, standard mech and shifter.

Thanks for your concern

 

[Big Bike Basher]

There's lots of Gimmicks. The Clutch isn't one of them. Most derailleur's have them.

Personally, if I ride a bike without a clutch the chain WILL come off the chainring - even if you have a chain guide.

If you have a clutch and a narrow wide chainring, quite often you can get away without having a chain guide as the clutch provides sufficient tension to keep the chain on.

Yes, 12 speed cassettes are on the whole unnecessary on an EMTB, unless you like to ride in Eco on the steeps.

If you're changes aren't smooth, this isn't the clutch. Either your derailleur needs adjusting (B Screw) or you're not easing off correctly as you make your change - so you're making full power changes and will just destroy your cassette in a much shorter time than if you make smooth changes.

If you're looking for advice, stick with a derailleur with a clutch even if you do decide to drop to 9 or 10 speed.

My changes are fine thanks.
As above I'm questioning the validity of the mech set up as it's crap in reality

 

[cozzy]

Crack on and do as you wish. No one really cares

 

[Big Bike Basher]

Crack and do as you wish. No one really cares

Why comment then

 

[cozzy]

Why comment then

Because you are clearly clueless and have been given advice from others you are choosing to ignore.

 

[steve_sordy]

........
My question was why the clutch on the mech when it's unnecessary.
............

If you look at pictures of mtbs on the cover of magazines from 8-10 years ago and earlier, you often used to see that the lower strand of chain was in a laid down "S" shape. This was the up and down motion of the bike traversing rough ground causing a skipping rope effect to make the bike chain whip up and down. The mass of the chain moving up and down would move the mech arm back and forth. With skipping ropes, or indeed any length of rope, you can make an effect that looks as though the wave is standing still. But on a bike, instead of standing still, the wave is more likely to move. If the low part of the wave reaches the chain ring, the chain can come off. This is one of the reasons why so many mtbs had chain guides. Many chain guides were mounted on the bike frame and positioned over the chainring, or you could have a dangler that hung from the bike (frame or a cable) but enclosed the lower strand of chain, stopping the wave from reaching the ring. The danglers were particularly useful on double and triple chainring bikes. With the advent of 1x, narrow-wide chain rings and a clutch on the mech, chain guides were not really necessary anymore.
All the clutch does is to damp the back and forth movement of the lower mech arm, reducing chain whip, or even stopping the wave from forming at all. The clutch tension is adjustable, so if it is too strong for your needs you can adjust it. Or just switch it off.

 

[TommyC]

What a nob

 

[irie]

Hmmmm.
Ok
Never had issues before with chain jumping off on bumpy descents.
Is it because the mech is so much longer to accommodate the 12 speed mahoosive cassette?

Where are the bumpy descents you ride on?

 

[Montana St Alum]

Oh it's rough where I ride.
Maybe Shimano have just made it a gimmick as I really don't see any benefits.
I will change the set up.
I'm going back to 9 speed and standard mech. This giant 12 speed cassette is ridiculous along with the mech...
Besides I think the 9spd chain and cassette will be stronger and smoother on changes.

You won't get an increase in ride quality or durability. No company is putting any money into quality materials or design improvements on 9 speed and haven't for many years. Also, you don't have to engage the clutch, if cleaning and lubricating it is out of the question. But, it's your money!

 

[Jackware]

Where are the bumpy descents you ride on?

It looks like BBB has left the building

 

[Ryawesome]

Hey BBB. If your goal is to minimize the size of your rear cassette and get rid of the 'gimmicky' clutch, then I see a couple options. One would be to convert it to a single speed, then, hey, small gear, and only one gear! Or, if you still want some range, then along the lines your your 9 speed cassette idea, make it a 7 speed cassette, but then a 3x drivetrain upfront! Who needs a gimmicky 1x drivetrain anyways, when a 3x worked perfectly well 30 years ago.

 

[John Beedham]

the Shimano clutch is a very good mechanism that does exactly what it is supposed too .... keeps the chain on the chainring in the rough, stops the chain from slapping around, eliminates the need for a chain guide ... basically introduced with 1x ... to compensate for the chain retaining effect of the, now absent, front derailleur. Easy to service ...lots of YT vids and if you don't like it ride with it 'off' ... no problem. Switch to 'off' when removing or installing the rear wheel or you will hate it!

 

[sanyata]

It also helps prevent "chain slap" where the chain is slapping the chain stay and damaging the paint, eventually gouging the aluminum or carbon stay.

 

[irie]

I have an xt rear mech. It has like a leaver on it that seems to lock it off.
Why is this on here please?

Just to piss you off, which it clearly has done.

 

[Bummers]

Baffles me why people ask a question to something they don't know then proceed to act like they know it all anyway.

 

[Bones]

Baffles me why people ask a question to something they don't know then proceed to act like they know it all anyway.

Hence why I bowed out early on

 

[SGS]

I mostly run with the clutch in the off position and have never had issues with dropping the chain. My cassette and chainring are now 2800 klms old and I replaced the chain at 2500 klm.