Perfectly align stem with wheel and seatpost? (Attn: Dave Rome)

So in the course of playing around with my stem quite often this week with various positions I noticed I spent a very unreasonable amount of time trying to perfect the stem alignment with the wheel. I know it’s straight but my brain keeps on playing tricks on me when I get on the bike and try to look down to the wheel.

Is there a jig by someone that easily solves this and also aligning round seat posts with the frame? :laughing:

@daverome - I am sure there is a tool for that which I am not aware of?

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I have never used it as I am too cheap to buy it.

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An alternative

Not cheap since it is def overpriced for a simple laser pointer.

Two laser line generators on a piece of MDF attached on the top tube. Align the front wheel and the beams, check the stem. Align the rear wheel and the beams, check the saddle rails.

I have a couple of cheap small laser levels with rotatable beams which I use for checking frame alignment,they would also work for this.

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I can get the wheel aligned from the front but when I look at the back / riding it pov. - it doesn’t seem right… :roll_eyes: :crazy_face:

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May I ask what’s the point in seeking such an overly perfect stem/wheel alignment? Even if you’d make it super-right to a subatomic level, your eyes dominance (one eye leading your POV) would make you still see it “wrong”.
As long the riding behaviour of the bicycle is not affected, alignment is ok.

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You can make your own at home jig with a fork mount and a piece of lumber but unless you work on bikes professionally that’s a bit overkill. I always find closing one eye and centering the stem plate with the front hub is the best option. Using the GPS mount isn’t good because some times those can be a little off angle depending on the shape/sweep of your bars or if the first time you mounted the mount and stem was off angle.

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A tip I once heard but haven’t tried (I just eyeball it):

Take out your front wheel. Loosen stem bolts.

Balance the front end of the bike on the ground by the fork legs and the handlebars (may have to remove shift levers). If your handlebars and fork are straight/symmetric and the surface flat, they will be aligned when all 4 points are in contact with the surface. Tighten stem bolts.

Try not to get hit by the rear end of bike swinging around :wink:

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Sounds promising

I don’t get this at all. Eyeball it in. If, after riding a bit, it seems off, move it a hair to one side or the other…it doesn’t really have to be rocket science.

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^^^This - otherwise we should also talk about the chirurgical means to align the length of your arms and the position of your shoulders (broke your collarbone? Oops) and how that’s covered by your health insurance.

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Why not just let gravity do it’s thing?
Hang the bike on a stand nose down, think the components (bar, shifters, wheel) are heavy enough to align them in the gravity field of the earth. Tighten bolts, off you go.
OTOH: eyeball, ride it for some km, you’ll get used to it. If distracted by misalignment, take a route that distracts you from that (views / cars). Your body will accept the feel, won’t it?

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Same method I use. I have a Bosch auto leveling crossed line tool that I use around the house. Works well for bikes too. Another use- measure saddle setback by leveling wheels. Then project vertical line through crank axle center. Measure setback from line to whatever place you want to use.

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If it looks straight, it is.

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Run a string line from the back of the saddle and above the front of the saddle, the steerer tube bolt and the centre of the stem. They should all line up.

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I double check by standing on the side of the bike, looking down at the stem and front wheel (or saddle and toptube). For some reason I find it easier to pick up if two lines aren’t parallel, rather than using one eye to line things up. YMMV.

I do this, but just leave the brake/shift levers in place. With the stem bolts loose, the two levers and 2 fork ends should rotate into contact with the FLAT surface (e.g. kitchen worktop). Carefully re-tighten the stem bolts before lifting the bike and replacing the front wheel.

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Take a long spirit level or any long object such as a broom stick that’s very straight and lay it on top of the tire against the fork. You’ll be able to quickly see if the handlebar is parallel or not with the level.

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I have one, and it never worked really well. The laser was super finnicky, and sometimes didn’t even work. Was wayyy overpriced.
Just sits in a bin now, and I’ll occasionally pull it out from time to time.

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