Well, given that I'm going to be stripping my old frame and rebuilding up a slightly less old frame (fingers crossed I get my hands on one reasonably soon) I'm toying the idea of losing my 3x9 setup in favour of a 2x9. Basically swap the large chainring for a bashguard and put a 36t ring on the middle.
Any thoughts? Anything to watch out for? Am I going to feel suicidal next time I'm out on a long ride lamenting the loss of my tall gears? Will Alfie and Kats marriage survive the month (sorry don't know where that came from)?
Obviously am going to shorten the chain appropriately, but anything else I'd need to do?
In the right ballpark... But with all the wrong balls...
I've not done it myself but I think the idea is pretty common.
You'll probably only miss the big ring on tarmac or on downhills, but if it becomes a big problem you could probably change the 36T to something bigger.
You'll need a 2 speed front shifter unless you find some way to stop the derailleur shifting onto the bash ring (e.g. very long adjuster screws).
I would have thought that the bash ring simply bolts on instead of the big ring. If it doesn't, check you don't need spacers/shorter bolts to hold the middle ring in place (had this problem when I converted my old triple into a singlespeed )
Would I definitely need a new 2 speed front shifter? Was kind of hoping I could continue with the 3 speed shifter just remembering not to shift up to the (non-existant) big ring.
You could use the 3 speed one if you trust yourself not to shift into the non existant ring.
You can swap the 'high' screw in the derailleur for a longer one (or if you're lucky screw the one you have in all the way), then if you try to shift onto the big ring the screw will stop it shifting that far.
You can run a 3 speed front shifter and a triple front mech but yow will get chain rub and a 36t requires more throw, get a double front mech and keep the shifter and it works much better that was my old setup, i have a Front SLX double mech top swing if yor intrested mate.