I cannot engage the granny ring while riding. it will engage if no pressure is applied (i.e. rear wheel off ground) I've set up the mech acc ording to various guides (adjusting limiter screws and cable tension)but to no avail.
could the problem be that the mech (an old one off here) isn't '9-speed specific' if such a type exists? should i ease off the inside limiter screw, forcing the mech to push the chain further across?
would love to go 1×9 but there seems to be no cheap option! (before you say it- tried SS but alas, it didn't work with the group i ride with)
any hints & tips'd be greatly appreciated 🙂

Forget 'various guides' and read

http://www.parktool.com/repair/readhowto.asp?id=75

It will talk you through the limit screws etc. You need to set them for each bike, so it sounds as if you missed that out when you installed.

I thought it was widley known that the front mech will struggle to drop the granny ring whilst under load. You always need to lift for a moment and it will go easily. Its all to do with the tension on the chain wrapped round the front ring.

Thanks for the help TooTall, that park tool guide did the trick. it was the inner limiter screw which was the problem. it all ran smoothly on a preliminary down the road run, will see how it fares in the 'real' world.

Stoney-yeah i knew about stepping lightly to change into it but it wouldn't even change on a flat with minimal load, let alone on any sort of incline so i figured something was askew

No probs Jeremy….i did`nt mean to state the obvious !!!

BTW, One of our Tues possy runs a 1×8 and all he has is a fornt mech to keep the chain in place. Seems to work a treat.

It's often the obvious things i forget to check lol
does he use a short cage rear mech?
how does he keep the front mech in the right position?
Did he shorten the chain?
nice idea, sounds do-able. i don't know whether any kind of guide is even necessary for non-boom-gnarly riding. i'll try botching something when i'm feeling pro-active heh