Is my stem straight . . .?

[bikeworkshop]

It's a mental problem.

Before you know it, you'll need a £150 bike fit, which will tell you your saddle is 2mm too high, bars 1mm low, crank arms 3mm too short, and you'll be blathering on about stack and reach and drilling holes in your retro frame to internalise cable routing to reduce turbulence

none of mine are straight. life is too short to care.

If it bothers you, close your eyes when riding.

^

 

[Woz]

I'm strongly in the mental "must be aligned" and "must be precise" camp.

Even though my body isn't; I doubt my arms are the same length.

Tend to be very obsessive when building the bike in the first place and I have noticed on cheaper stuff a lot isn't that precisely made to begin with. Also the markings on some of the bars and stems is actually off and can't be trusted. That drives me well nuts.

Personally don't use the stem / front wheel imaginary centre line method; use the perspective of front fork drop-outs or wheel axle and the rear of the handlebar looking down (one eye at a time) standing over the bike. It's like aligning two horizontal lines to be parallel if that makes sense.

Always wanted to make a proper jig for this (and other) sort of things.

 

[bikeworkshop]

You could make a jig with around 2 metres of string:

Wrap string round the qr and up and round the bars - each side, symmetrically.

Then look at the 2 near vertical strings from the side and turn the bars until they are perfectly aligned.


Bingo.

 

[Splatter Paint]

It takes me at least two times, if not 3 or 4 to align a stem. I static align, then ride, check, adjust, check again then torque to spec

 

[Woz]

You could make a jig with around 2 metres of string:

Wrap string round the qr and up and round the bars - each side, symmetrically.

Then look at the 2 near vertical strings from the side and turn the bars until they are perfectly aligned.

Bingo.

String? I'm not a farmer with a ball of twine you know. I don't do nor own string.

When I say jig, a thing like a marble optical bench with graduations, calibrated low dispersal lasers and precision polished silver mirrors. Then lots and lots of high end clamps, set-squares, fixtures and what not. Something like that used for the R&D in optical computing or space exploration.

I'm sure Lidl will be having them any time soon.

String. Tut ...... give over.

 

[benjabbi]

You can buy a laser guided tool for this.
https://www.superbiketool.com/en/product/detail/Frame_Fork/TB_HD05
I just get it as close as possible by eye, usually lining the front of the bar up with the fork crown. Then do it again after the first ride when I realise it's well out.

 

[2manyoranges]

Rule 6
No mechanic can set a stem or saddle straight…ever

Rule 236
Relax

 

[bikeworkshop]

How about point your bike due north, ride with a spirit level on the bar, just watch the bubble.


After 10 minutes of riding see where you're at.
If you've swung West, your bars need to be turned to the...

Well, no need for polished granite, lasers and breathy assistants in tight-fitting lab coats @Woz

 

[Suprachrgd82]

With my aging and increasingly more crooked aching body, I find it impossible to physically detect any misalignments in the bike. I frequently see it, but I can't feel it.

 

[Woz]

Once made a jig to measure fork crown to axle length and fork rake.