How to adjust adjustable road stem?
 

http://www.performancebike.com/shop/...4&PID=1684032#

Cannot get adjustable road stem to "adjust"

No instructions came w/ it.

How much force should I place on the adjustment to rotate. Tried fair amt of force, and no dice.

I'd disassemble it and figure out what made it tick before putting ANY force on it. :)

I'm guessing that the two surfaces are serrated inside, so you have to loosen the bolt and possibly gently pry them open. Ihope they're heavily serrated because otherwise there's no way they'll hold up. So yeah, remove the screw and see what it looks like. Not rocket science.

Look at the underside of the stem. There's probably a little finger hidden under there that you have to nudge out of the way before the stem angle will change. Be sure to push it back in or it won't stay where you set it.

Ditto on looking underneath. My wife's bike has an adjustable stem, and it has a bolt underneath holding the stem into a serrated finger that keeps it from slipping.

I had one but it would not fit my wider handlebar diameter - you unscrew completely and has to push out the mated "bolt" side - I need to use something like a nail punch or setter. And, yes, the "teeth" grab each other once tightened.

Had to be completely disassembled, then one side PUSHED out of place, not pulled. Sorry, hard to explain. Thanks.