Rear Derailleur Upgrade Help

[The Brewer]

I have an 8 speed chain and cog set on my mountain bike and want to upgrade from a Shimano Alivio derailleur to a Shimano XT.
Do I need to upgrade my cassette to a 9 or 10 speed cassette and if so do I need to upgrade my rear hub as well?

[Painkiller]

what year is your bike or a few pics would be nice. and need to know what teeth your cluster range would be. but as you state now yes you would have to replace your hub so hang tight and get us some pics

[The Brewer]

My bike is a "GT Avalanche 3.0 Disc", im not positive what the year is But I purchased it in 2011. I'll get some pics asap. Thanks for the feedback.

[Painkiller]

I would recommend an rd-m750 it is an older model more for an 8speed drivetrain. i could not say that the new xt would have the limit screw capacity you need without trying out. try to find a new old stock 750 like on ebay. I have seen them before

[Painkiller]

(01-22-2012, 02:02 PM)painkiller Wrote:  I would recommend an rd-m750 it is an older model more for an 8speed drivetrain. i could not say that the new xt would have the limit screw capacity you need without trying out. try to find a new old stock 750 like on ebay. I have seen them before

here ya go
http://www.ebay.com/itm/SHIMANO-Deore-XT-RD-M750-Mountain-Bike-MTB-Rear-Derailleur-9-Speed-Long-Cage-/320827768715?pt=Cycling_Parts_Accessories&hash=item4ab2d33f8b#ht_1411wt_1397
this would work nice for you

[nfmisso]

(01-22-2012, 01:04 PM)The Brewer Wrote:  I have an 8 speed chain and cog set on my mountain bike and want to upgrade from a Shimano Alivio derailleur to a Shimano XT.
Do I need to upgrade my cassette to a 9 or 10 speed cassette and if so do I need to upgrade my rear hub as well?

You can just swap the derailleur - but it would be a good time to replace you chain and cassette; and redo your wheel bearings.

If you elect to go to 9 or 10 speed, you'll also need to replace your shifter.

8, 9 and 10 speed Shimano cassettes use the same freehub.

[easy83]

(01-23-2012, 05:18 PM)nfmisso Wrote:  

(01-22-2012, 01:04 PM)The Brewer Wrote:  I have an 8 speed chain and cog set on my mountain bike and want to upgrade from a Shimano Alivio derailleur to a Shimano XT.
Do I need to upgrade my cassette to a 9 or 10 speed cassette and if so do I need to upgrade my rear hub as well?

You can just swap the derailleur - but it would be a good time to replace you chain and cassette; and redo your wheel bearings.

If you elect to go to 9 or 10 speed, you'll also need to replace your shifter.

8, 9 and 10 speed Shimano cassettes use the same freehub.

This is exactly what I was looking for, I have the same problem. My question is that the shifter actually dictates what the derailleur does?
So as long as you use an 8 speed shifter or upgrade everything there won't be a problem? I thought the 9 and 10 speed had a narrower chain.

[Joe_W]

(03-16-2012, 03:15 PM)easy83 Wrote:  This is exactly what I was looking for, I have the same problem. My question is that the shifter actually dictates what the derailleur does?
So as long as you use an 8 speed shifter or upgrade everything there won't be a problem? I thought the 9 and 10 speed had a narrower chain.

In principle yes. The dérailleurs still work. I have some setup like this (a 9 spd RD on a 7spd bike). The amount of cable pulled "just" has to be compatible (which it is when sticking to Shimano stuff except for some exotic stuff).