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Accurately finding the centre of a flared drop bar

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I've just been playing with some bits for my next gravel build and realised that the specialized compact, flared drops I got lack any markings to identify the centre, there's a black 'S' logo centre, front, that will be hidden beneath the stem face plate.

So I need to put a little dab of paint on the centre to help me bolt everything together later, but how should I go about finding the exact centre seeing as everything is a curve or an angle. I've got a couple of ideas, but I was wondering if anyone else has tackled this issue before and come up with any ingenious methods...


 
Posted : 26/01/2025 1:10 am
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Tape measure from the inside of each side of the forward extension, divide by 2?

Each side should be identical despite any curve or flare unless the bar is bent.


 
Posted : 26/01/2025 1:47 am
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Or a piece of string, then fold in two.


 
Posted : 26/01/2025 4:04 am
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Do it in the bike with the front wheel straight measure from the end of the bar to the top tube. No need for a paint dot then.

Or just eyeball it and call it done, would probably be my solution.


 
Posted : 26/01/2025 5:59 am
leffeboy and leffeboy reacted
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Put the 'bars on the floor at right angles to a perpendicular wall. Push them against the wall with a block of wood, also on the floor at the opposite end. Measure the gap

Halve that measurement and measure from the wall to the stem area. Simples 🙂


 
Posted : 26/01/2025 8:54 am
 loum
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Use the walls in the corner of a room to hold it square, measure across, half it, measure along.

Edit. Cross post. What he said.


 
Posted : 26/01/2025 9:09 am
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Balance on a blunt knife. Make sure the bar is level. The knife is at the centre.


 
Posted : 26/01/2025 9:19 am
hardtailonly, convert, hardtailonly and 1 people reacted
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Balance on a blunt knife. Make sure the bar is level.

On one leg or two?


 
Posted : 26/01/2025 9:20 am
thols2, leffeboy, MoreCashThanDash and 3 people reacted
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As above but on a performing seal's nose.


 
Posted : 26/01/2025 9:21 am
thols2, convert, convert and 1 people reacted
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Rubber band on the bar through the centre of the S then mark in a spot that won't be covered?


 
Posted : 26/01/2025 9:29 am
frogstomp and frogstomp reacted
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If you are happy that the logo is in the centre, just hold it up to the stem without the faceplate and mark where the sides of the stem touch the bars.


 
Posted : 26/01/2025 9:32 am
kayak23 and kayak23 reacted
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Masking tape across the bar top. Mark the edges of the logo in pencil then mark the centre.

Measure stem clamp width. Measure out from your centre mark each side half this measurement.

Wrap a little tape around the bar say just outside each mark, remove any tape that'll be under the clamp.

Fit the bar with the width tape as your guide


 
Posted : 26/01/2025 9:48 am
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I've got a cunning little tool from Abbey Tools that screws into the SFN and then allows the derailleur hanger alignment tool to screw into that. I can then use this to centre the bars, or check lever position on drop or flat bars.

Pretty sure someone will do a cheaper version.


 
Posted : 26/01/2025 9:49 am
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Fit and measure with a tape measure.

Adjust by the appropriate amount.

Didn't seem that hard when doing the woodchoppers. They were still fairly rigid and unchanging in length.


 
Posted : 26/01/2025 10:14 am
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Eyeball it, and if you can't tell the difference between left and right, that's all you need.


 
Posted : 26/01/2025 11:01 am
convert and convert reacted
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All my bikes are built by eye. Prob not a great idea TBH as my left eye is very weak, but seems to work for me. Bars on my gravel bike had no markings either.


 
Posted : 26/01/2025 11:03 am
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Nothing too helpful to add, as mine were done last week by LBS as a nice upgrade to my Synapse, gratuitous pictures though ?

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Posted : 26/01/2025 11:05 am
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Measure from the centre of the lower right stem bolt, to the inner edge of the lower part of the bar. Repeat on the left side. Adjust bar position until they are the sane


 
Posted : 26/01/2025 12:11 pm
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Put the ‘bars on the floor at right angles to a perpendicular wall. Push them against the wall with a block of wood, also on the floor at the opposite end. Measure the gap

Halve that measurement and measure from the wall to the stem area. Simples ?

Something like that was probably going to be my method, I was hoping someone else had a genius solution I'd not thought of.

I think they're OEM bars, serves me right for buying cheap, but it's sort of mind boggling that they have no useful markings for fitting/adjustment, I've not come across any other bars like this before, I assume the poor mechanics PDI-ing specialized bikes get some sort of jigs(?).

Cheers all.


 
Posted : 26/01/2025 2:29 pm
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Postal elastic band around each end, measure middle and mark, align to head tube. Done.

mine came ready marked though. Rather like them. IMG_5978


 
Posted : 26/01/2025 4:55 pm
 mert
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flared drops I got lack any markings to identify the centre

Pfffft, i've had dozens of sets where the helpful markings weren't even IN the centre


 
Posted : 26/01/2025 9:07 pm