Ok, currently run 2×9 with 22/32 on 660 slx cranks with outer bash and a 11-34 cassette. Looking at 2×10 or 1×11. I think 2×11 will be a little too expensive with the extra shifter and front mech.
For 2×10 can I use 9 speed front chain rings on my 9 speed cranks or do I have to go 10 spd 24/36 etc – if I recall sometimes there is an issue with 10 speed middle chain rings not fitting the spider on 9 speed cranks?
Regarding 11 speed, looking at 11-42 XT with a NW 30T chainring. Again, would this set up be ok on my 9 speed cranks. In terms of ratios in simple terms what would the lowest ratio be compared to my 9 speed set up. Will I be say missing the lowest gear on my 11-34 granny ring? Finally, pretty sure the XT shifter can fit onto my ispec B Deore 615M Brakes – is this correct.
