Stem alignment tool

[Milzy]

After 20 years I’m fed up of eyeing up guessing the bars centre.
What a good stem tool to use to make sure the stem is perfectly in line with the frame?

 

[midlife]

Does the stem need to be perfectly in line with the front wheel or am I mis reading the question ? .

 

[Jenkins]

Plenty of the cheap ones that clip onto the handlebars and shine a thin line of light onto the tyre for alignment

Just search for Bicycle handlebar alignment tool in your favourite search engine.

Edit - if turned round the other way they also shine the light on the seat so you can check that's in line as well.

 

[super_davo]

Plenty of the cheap ones that clip onto the handlebars and shine a thin line of light onto the tyre for alignment
View attachment 816095
Just search for Bicycle handlebar alignment tool in your favourite search engine.

Edit - if turned round the other way they also shine the light on the seat so you can check that's in line as well.

I have one of those and I love it... not much more than a fiver from AliExpress and dead easy to use. My 'eye guessing' generally was pretty close without it but now I can the get alignment perfect, and probably more importantly have full confidence I have got it perfect.

 

[sevenfourate]

How do you know if the tool is dead central on the bars……

 

[Vapin' Joe]

How do you know if the tool is dead central on the bars……

You'll know the first time you ride the bike.

In all my years cycling I built more bikes than I care to remember, and never once did I manage to get the stem straight by eye. It always took a ride down the road with an Allan key in my pocket and a bit of fettling before I got it straight.

Of course, all this could be simplified if the manufacturers put a centre line up the back of the steerer tube, but none ever have.

 

[Seevio]

Out of interest, does anything bad* happen if the bars are not aligned dead centre or does it just look/feel wrong?

* I was thinking bike related rather than earthquakes, biblical plagues, portents of the end times etc...

 

[sevenfourate]

You'll know the first time you ride the bike.

In all my years cycling I built more bikes than I care to remember, and never once did I manage to get the stem straight by eye. It always took a ride down the road with an Allan key in my pocket and a bit of fettling before I got it straight.

Of course, all this could be simplified if the manufacturers put a centre line up the back of the steerer tube, but none ever have.

It was kind of tongue in cheek - but I hear you ! I too have built (50 ?) bikes from F+F up. Probably taken apart / changed stems (And so had to realign bars) 1000’s of times (?) And riding / looking / adjusting is about as good as it gets imo. And I’d fancy my by-eye OCD / tape measure / string line methods over most other options of alignment.

I’m also very aware if the Laser tool isn’t on the bars absolutely dead square or even tilted slightly: a small amount of imperfection at the device - could be far more margin at the wheel than my extremely keen Engineers eye could have spotted in the first place.

The laser alignment idea is fantastic - that’s a given. I’m just aware if your Datum isn’t 200% correct: you’re adjusting to that; and achieving a less than perfect result……

 

[Vapin' Joe]

Out of interest, does anything bad* happen if the bars are not aligned dead centre or does it just look/feel wrong?

* I was thinking bike related rather than earthquakes, biblical plagues, portents of the end times etc...

Believe me, a couple of mm out and it looks and feels wrong and drives you up the wall.

 

[Seevio]

Believe me, a couple of mm out and it looks and feels wrong and drives you up the wall.

I get that, but bits aren't going to fall off or break, right?

I was originally going to say just adjust it until it feels right and don't worry about being exactly central, but after having a think I realise I would be a bit hypocritical after posting the electronic shifting thread. So if you can get tech to save time setting things up, go for it. specially if its cheap.

 

[Drago]

Out of interest, does anything bad* happen if the bars are not aligned dead centre or does it just look/feel wrong?

* I was thinking bike related rather than earthquakes, biblical plagues, portents of the end times etc...

Every time someone rides a bike with un-centred handlebars Cliff Richard has a number 1 hit. Its particularly nauseating when it happens during the Christmas season.

 

[Venod]

Every time someone rides a bike with un-centred handlebars Cliff Richard has a number 1 hit. Its particularly nauseating when it happens during the Christmas season.

Congratulations on your reply, a written reply is good, as we don't talk anymore.

 

[ColinJ]

However you set about achieving your perfect stem alignment, there is one little extra detail to get right...

I was putting some new bars on my singlespeed bike when I was distracted by a phone call. I finished the call and decided to go out for a test ride. All was well until I tried turning down a side street... The bars turned just fine but the bike carried on in a straight line - I had forgotten to tighten the bolts holding the stem on the steerer!

 

[Drago]

However you set about achieving your perfect stem alignment, there is one little extra detail to get right...

Indeed. No matter what the ideal fitment is for any given rider, stems must always be fitted with any visible script upside down amd a random number of stem spars mounted above.

 

[Sharky]

Allan key in my pocket

Good practice, any job I do on my bike, I always carry the tools I used with me for the next few rides.