Shimano deore thumbshifters running 8 speed?

[frank.youngman]

I tried this and to be honest I could not make the indexing work,however much I fiddled.There was tendency to jump two gears towards the ends of the cassette,although obviously it was OK in friction mode.

In the end I just used a seven speed cassette with a spacer ring wherever I was using an eight speed hub.

 

[legrandefromage]

Must be something in the set up somewhere as the spacing for 8spd is 4.8mm with 7 at 5mm. The last 'shift' involving the 8th cog is the extra click so there shouldn't be an issue further down with the 2mm float in the top jockey wheel.

I have used this setup for years since I got my hope ti glides back somewhere in 1996.

 

[Silvergoat]

There's any number of variables that can affect shifting and drivetrain performance. The old 'extra click' 7speed Deore thumbshifters does seem to run sweet 8speed in either friction or index. I've combined my Deore thumbshifters with:

Goodridge cabling
8speed HG51 cassette (11-32)
XT M772 Shadow 9speed GS medium cage
SRAM PC870chain
36t & 50t rings (summer), 34t & 46t (winter)

For me, any shifting issues have been with chain length/tension, cable tension, adjustment of rear mech. Switching from my old DX rear mech to the modern XT has cut out a lot of frustrations.

 

[SEANSTEPHENS]

lm looking to run an xt m732 thumbshifter with an xtr m900 8 speed rear mech. Cassette i havent decided yet but im assuming at this point it would be best to keep it all shimano.

 

[Retro_Roy]

hi
this thread is timed right.
I've got a build on the go to try deore 7speed thumbshifters and 8 speed also.
picked up a set of wheels with bullseye hubs and a sach 8 speed cassette.
thought I'd try it instead of going thru the trouble of swapping for a 7 speed
cassette. or should I swap cassettes? never changed a screw on freewheel before either.
also not sure of which 7 cassette speed would work. opinions please.
should I address all this in a separate thread? bit off topic.
thanks
roy

 

[legrandefromage]

Sunrace do good 8spd screw on cassettes

 

[Neil]

The Deore 6spd and XT 6spd thumbies can run 7 - SL-MT60 & SL-M730

The DX 7spd and XT 7spd can run 8 - SL-MT62 & SL-M732

I cant remember if my nylon 200GS thumbies did 8 though.

The DNP Epoch 7spd thumbie DX clone can only do 7.

the 'clicks' are usually quite pronounced btw

Just to point out, you can get DNP Epochs in 8 speed versions - I have a couple of NOS pairs - no friction mode, though.

And Sunrace also do some DX 7 speed copies - don't think they have a hidden click, and also don't think they have a friction mode.