Techy question

[Russell]

I'm running a brand new 8 speed XT cassette, 11-28, XT 7spd thumbies, M900 rear mech and new cables.

Why does it not shift correctly around the 3-5th sprockets?

I seem to remember some one mentioning there was a difference in spacing of 'brand new' 8 spd cassettes but don't remember who it was or the cure!

Help!

 

[Stick Legs]

I had the same problem...

You need to set the mech up perfectly in the middle of the problem zone and work from there.

The other option is to space the bottom half of the block with 7 speed spacers and leave the top half alone. This makes the lockring a bit of a tight fit but if you are careful you can do it. The top cogs are not so sensitive it seems.

I have given up and gone 7 speed, off road I found a 12-23 does what I need it to, and has the same spacing as a 12-28 8 speed.

 

[Russell]

Cheers Pete.

So what are the people using that have an 8spd set up with thumbies?

 

[Stick Legs]

I guess they must still be using the old blocks... I expect to see more people having problems in the future as the old blocks get replaced.

 

[Russell]

Booo. There must be a stock of NOS 8speed cassettes somewhere.

<<goes hunting>>

 

[mikee]

try a 9speed chain

 

[Russell]

try a 9speed chain

Ahhh! I like your thinking!

<<stops hunting for old 8 speed cassettes and rumages in the garage for a 9spd chain>>

 

[sunchaser]

My mate today built-up my Kona with XT M737 f & r mech's XT 7spd thumbies & a 'new' 8spd cassette. As far as I know he had no problems... time will tell though I guess.

 

[leonatico]

I´ve been using my 7speed XT thumbshifters since 1992 passing them on to my new bike each time and have passed through many 8 speed cassetes (new and second hand), and had problems only once (2nd and 3rd sprocket) and I blaimed it on them being worn out(2nd hand)... Anyway, now I´m using an 8sp XT cassette with no problem as long as you keep the cables nice and clean. I don´t know what year it is but when you look from the inside it´s got a 4 arm spider that holds it together, not like the old ones, almost solid.

Un saludo.

 

[leonatico]

btw, my bike's got a Sram Plasma 8sp. The ones with orange wheels, I´ve seen them on a Kona Hei Hei from this forum also.