Ratt said:
Back in my 8 sp days i used to run a 20 tooth granny with a 11-32 xt cassette and have a lower gear ratio than a 22t with a 11-34 9speed.
You can still do this. I am currently running a 12-32 8sp XTR cassette (the one with three ti-cogs) available at Cambria, XT 8sp shifters available from various sources, XT 751 9sp crankset (the first model with the Shimano splined BB), and a 20 tooth granny chainring available from
Action Tec!
As Ratt said the 20-32 actually gives you a slightly lower gear than the usual 9sp 22-34. The trick to running the 20 tooth chainring on the now standard 64mm 4-bolt crankset is that in my particular case I had to use a dremel and a file to remove a bit of metal from the spider to make it work.
Let's see if I can explain this simply: The spider has four lugs where the small chainring actually attaches. The chain will barely touch the chainring bolts while wrapped around the 20t chainring in an ideal situation. The trouble was with the lugs that the small chainring attaches to being slightly larger in diameter than the chainring bolt heads. So, the chain was hitting the lugs and not making full contact with the chainring in that particular chainring valley. I simply used a dremel and a file to remove just enough material from the lugs so that the chain rested more securely in the valleys of the 20t chainring. A tip is to screw the chainring bolt fully into the lug before performing this surgery. With a steel or ti chainring bolt there is little chance of damaging the bolt and it will serve as a guide for approximately how much material to remove (do not use aluminum bolts). You only need to remove enough material around the top radius of the lug to allow the chain to fully seat on the chainring.
Using the 20-32 combo is a huge upgrade in climbing performance vs. the 22-32. So, now I live in a perfect world. I have bullet-proof 8sp shifting, the light weight XTR ti cassette, and a 20-32 granny to more than match the standard 22-34 9sp climbing ability!