Bicycle Mechanics - How to align stem with fork?

So I did some stem moving, how do I get it so that I align the stem/handlebars with the fork/wheel? This is a threadless set with the stem separate from the other parts... I've been trying to eyeball it over and over but I can't rest until I know it's straight on. Is there any method you guys use to do this or is this just meticulous correction?

The current RoadBikeRider newsletter addresses this exact problem and here are three suggested methods from their reader feedback:

Jan: Attach a long, straight stick (like a broom handle without the broom) to the handlebar. This will make any angular discrepancy between the handlebar and the frame easily apparent. That, and you can measure the distance from the floor to the ends of the stick if you are really uptight.


Mike: Take off the front wheel and wedge a 3-foot-long straight wooden dowel into the dropouts. Leave roughly equal lengths sticking out each side. This provides an excellent visual reference against which you can align the bar.


Dave: Lay a metal yardstick on its edge along the stem, sticking out over the front wheel. Carefully center it over the handlebar clamp. (These clamps often have a logo or faceplate bolt that is centered exactly, so this spot is easy to find.) Now the yardstick marks the exact centerline of the stem. The projecting end of the yardstick should exactly bisect the front tire if the stem is straight in line with the bike. Adjust until it does.

I personally find eyeballing to be the most accurate. I'm pretty good at it. I can also hang pictures without using a level.

1. Eyeball it
2. have a beer
3. look closely at it from every possible angle
4. if a discrepancy is found go back to step 1, repeat until you don't care

Take a short ride and glance down. I can usually tell pretty quickly, when I'm having to hold the bars crooked to go straight. Also, while looking over the bars, line the tips of the fork up with the front edge of the bars. That usually is a good way to tell.,,,,BD

SWAG method FTW.

I have messed with the stem several times now trying to get it just right for fit. Ive become pretty good at getting it lined up nicely. If you just put your legs around the wheel, and remove the stem/spacers quickly enough without moving it around, you can get it back on easily without to much fuss. Right now it's not dead center straight, maybe 1-2 deg difference, its really no big deal i think unless your racing or something.

why not use a plumb bob

...... its really no big deal i think unless your racing or something.
It's a REAL big deal to many of us and will drive me nuts until I get it right. That's not logical but that's the way it is.

If you are going to "eyeball" it, be sure you are straddling the bike as you align the stem. You can't do it from the side.

The only true test is to ride the bike. I've found that a lot of times it seems to be off when I'm trying to eyeball it standing still, like when I adjust my stem. Then when I ride it I either notice it or not. If not, well, that's it. If I do notice it, I just note which way and adjust as necessary next time I have the chance. Repeat.