I understand that I can whack a 9speed cassette on my 8 speed XTR hubs with no worries. If this is the case, is it also possible to upgrade my shifters and rear mech to 9 speed now, but keep my cassette as 8speed till it wears out. Will the gear indicators just not click into the 9th gear?
Also, what are peoples opinion of SRAM shifters. Back in the day I was a huge Gripshift user, but since I've been out of the loop, I don't know. Are the trigger shifters a good mechanism?
Answer to question No 1 is No it won't work, your shifting will be all out of whack and the chain won't fit the cassette if you change it or the rear mech if you don't.
I've never used SRAM shifters so I'm not going to comment on how good they are.
I wouldn,t call going from 8 speed to 9 speed an upgrade , quite the opposite . 8 speed is much more reliable , stronger and cheaper while you can still get the parts . Shifters whether Shimano or Sram are very good and it,s pretty much a matter of personal preference what works best but 8 speed works better than 9 .
Your shifter, cassette and chain must match i.e. all 8 speed or all 9 speed. You can get away with mismatching mechs.
The 9 speed Deore cassette is a bit mud-prone, but 9 speed XT is pretty good. It isn't worth upgrading though, unless your components are worn out anyway.
I'm in the process of upgrading from 8speed to 9 as my drivetrain started to wear out.
I've got 9 speed mechs and chainset (all LX) with 8spd shifters, cassette and chain. When the cassette goes I'm quite tempted to finish the upgrade and get 9spd versions. The reason I want to go 9speed is the 34T rear low gear which makes the middle ring much more usable when climbing those extra steep uphills.
But to answer your question - I'm pretty sure 9 speed shifters will only work on a 9 speed setup.
You can do what I have done as a half way house, but it won't work the other way round.
By the way 9speed mechs are much better than the 8speed ones (unless you can get hold of an older XT/LX one) even running on 8 speed - much smoother and quicker gear changes.
Ahhh....cos back in the day when 8 speed first came out, people were using DX/XT thumbies with their mysterious extra click...of course, that meant the lever just went further around so obviously the ratio of cable pulled now is different.