You need to go over Dan's articles on fit and front end makeover on this site. It is all in there, honest. The right stem is the one that doesn't leave you too stretched out or too cramped. Either problem messes up the right angles.

It is best to either get an adjustable stem or buy three or four stems of various lengths. You will dial in eventually.

The other thing would be to post a picture. More knowledgeable people than I will give you some pointers.

For stem length, I've read (I don't remember if it was on this site or in a JCobb article) that your h-bars should be 1-1.5" away from the end of your fingertips when you place the back of your elbow against the front of your saddle. Assuming you know the seat angle at which you're most comfortable, this method should give you an idea.

Next, Dan has a formula for calculating the arm-rest drop based on your seat height and angle. You'd probably have to do a little math to calculate how that translates to stem drop/rise, but you could probably do it.

Or, you could just private message me your address and I'll send you the stems that I have lying around (all basically new and purchased while I was on the same stem-fitting quest as you). It would at least let you play around and help you figure out which one you need.

Oh yeah this is for a road position. I lost my aerobars while diving to the shop for help adjusting the aerobars. Stupid story really.

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