SIS thumb shifter - what's this lever for?

[Chris S]

I've recently bought a bike with a SIS thumb shifter. It has a small additional lever in addition to the main one. Does anybody know what it's for please?

 

[Sharky]

Is the big lever for shortening the cable. ie moving to bigger sprockets and the small lever to release the cable to move to the smaller sprockets?

Just a guess.

 

[dan_bo]

Switch between friction and index.

 

[raleighnut]

^^^^^^ yep

 

[Chris S]

Switch between friction and index.

Thanks - I'll give it a go.

 

[dan_bo]

Thanks - I'll give it a go.

At least that's what it does on my old XTs.

 

[craigwend]

I've recently bought a bike with a SIS thumb shifter. It has a small additional lever in addition to the main one. Does anybody know what it's for please?

View attachment 610596

It's the SIS equivalent of the 'red button' (don't press it...)

View: https://youtu.be/nA8ipXtzHrY