What kind of torque wrench do I need to buy to tighten the allen head bolts on my stem, and how much can I reasonably expect to pay? Also, is there a generic torque spec on stems, or is it stem specific?
Well, you could buy almost any torque wrench, but you might want to buy some allen head sockets. I do a lot of automotive work, so I have a top of the line craftsman torque wrench. It snaps when the set torque is reached. There are other kinds (that have a pointer on the handle) that are fine if you can see what you are doing. Should be good for bike work.
2005 Giant OCR3
2004 Trek 4900
1999 Giant Rincon
What I don't like are stemps with no markings at all about torque. For those, I go by feel and by guess. But with a torque wrench, I can even then make sure that at least both bolts are tightened identically. Even without a torque spec, I believe there is value in having both binder bolts at equal tension.
I like torque-drivers for lower torque value fasteners.
I'd use a 1/4" drive beam wrench. It needs to read low range torque accurately.
Other than the obvious part about buying a torque wrench which ranges around the torque you want to measure, don't buy it from a bike company. Mind you I'm sure the torque wrenches from Park work great, as do the one from the guy I met at Interbike a couple years ago. However, they cost at least twice as much as a comparable one from a place like Sears, and I'm not convinced that they are any better.