Clutch Equipped Deraileurs

[Mongoose]

New to e-bikes... I see that many Shimano rear deraileurs have a clutch mechanism that appears to increase chain tension... When should the clutch be engaged and disengaged?... I ride roads and relatively smooth trails... No single track, etc.

 

[Sierratim]

The derailleur clutch mechanism is intended to reduce 'chain slap' where the derailleur 'shortens' on a bump allowing the chain to hit the bike's chain stay. The clutch doesn't so much increase chain tension as reduce the ease with which the derailleur arm can move.

We also ride mostly roads and smooth gravel trails, but leave the clutches 'ON' for the occasional pot hole or root. So far no 'scars'on the chain stay protectors that came with the now 1 year old ebikes.

OTOH - We ride our mechs over similiar terrain. They are not equipped with clutched derailleurs. Their chain stays show multiple 'wounds'.

Seems worth leaving the clutch 'ON' to me.

BTW - The clutch does need to be in the 'OFF' position to remove the rear wheel.

 

[Mongoose]

Thanks for the advice Sierratim!

 

[Sierratim]

Forgot to mention that having a clutched derailleur will also reduce 'chain drop' on the front chain ring(s), at least with the clutch 'ON'. This is esp important if your ebike has a single front chain ring. This is our setup. Neither of us has dropped a chain on the new ebikes over the year we've had them, but have had one or two on our mechs, again always riding with the clutch 'ON'.

 

[StmbtDave]

I read the online operating manual for my Shimano GRX derailleur and came away with the understanding (right or wrong) that leaving the clutch OFF when riding on the road would make shifting smoother. As Sierratim said, having it in the ON position when riding off pavement will reduce chain slap.

 

[Sierratim]

I agree. The clutch makes the derailleur arm harder to move, therefore a bit stiffer shifting. I have tried both and can't really tell a difference.