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Why doesn't anyone use flat bars anymore?


Scoox

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I ride an Echo mod and I‘ve got the following bits at home:

  • S1 (Stem 1): 150 mm x 35°
  • S2 (Stem 2): 175 mm x 35°

And...

  • H1 (Handlebar 1): 740 mm length 75 mm rise, 10° both up and back sweep
  • H2 (Handlebar 2): 740 mm length, 100 mm rise, 3.5° upsweep, 10° backsweep
 
So far I have tried the following combinations:
 
  • S1+H1 - Tried it, too low, causes me to crouch
  • S1+H2 - Not tried yet
  • S2+H1 - Currently running this, feels ok-ish but pushes front wheel forward, so I rotate it forwards, which cases grip discomfort
  • S2+H2 - Makes rear wheel handling very easy, but front wheel moves and up-to-rear moves require too much arm extension.

S1+H2 is the last thing left to try and I don't think it's going to be any better than the other set-ups.

So I've done some research. I've watched a bunch of videos and noticed many riders rotate their bars forward, in such a way that the "V" bit of the bars is aligned with the stem. By doing this they are able to pull the bike closer to the rider while on the rear wheel, which basically requires less effort to keep the the bike upright, i.e. it makes the bike feel more like a po-go stick. In other words, cockpit reach can be adjusted by rotating the bars. But there's a problem with this, because rotating the bars also affects the way the hands grip the bars, that is, the grip angle. Our hands have a natural "optimal" angle which we cannot change, and really we should build our bikes to suit our anatomy not the other way round. So rotating the bars should only be done to adjust grip angle, not to adjust cockpit reach.

This is where flat bars are superior. With flat bars, reach is virtually the same for any rotation, therefor with flat bars the only way to adjust cockpit reach is by using a different stem. I've done some 3D drawings to see how flatbars compare with riser bars, and my conclusion is that a long stem with flat bars is better than a short stem with riser bars, the latter being the most popular configuration at the moment.

Check out some drawings (you can see and download the Fusion 360 3D model here). Notice that "upsweep" and "backsweep" angles are a single angle in 3D space.

Here is an overview of my 3D model, it's a dual-height stem: 135 mm & 175 mm, respectively, angle is 35° . The bars are roughly modelled after H1 and H2 mentioned earlier. In this drawing the riser bar and the flat bar have the same angle to make the comparison more obvious:

5a9acc357ac75_2018-03-04-002344StemBarHomeview.thumb.png.fca69f75220c9b1963b637603a545317.png

Now let's check out some views. First, this is what the set-up would look like when the bike is on two wheels. In this example I've position both bars so the grips are parallel. You can see the riser bar places the grips slightly higher:

5a9acd1ecc038_2018-03-03-234445BarStemtwowheels.thumb.png.8a34bf126e89eff953c481123290d6f1.png

Now here's what the above assembly looks like when the bike is on the rear wheel. Her you can see how the riser bars are much closer to the rider, which means the front wheel must be further from the rider:

5a9acdc50a33f_2018-03-03-234338BarStemRearwheel.thumb.png.9bfdb93b01db44eb43b1b1b972ba7226.png

Because riders want the front wheel closer to their body to make rear wheel moves easier, they compensate by rotating their riser bars forward, as shown below. Unfortunately, this causes overpronation of the hand, when the hand's natural position is one of slight supination. Here's a video showing what those fancy words mean. It also casuse uneven pressure distribution over the palm of the hand, specifically putting more pressure on the area of the palm at the base of the pinky, while the area at the base of the ring finger does less work. This can cause hand and wrist pain and flappers.

5a9ace18b2d6d_2018-03-03-234552BarStemcompensating.thumb.png.bb2a5e2a8152f1eed06ab5dc7f8ed2b6.png

So, in short I think I'm going to get some flat bars and pop them on a long stem. I was just wondering if anyone had tried this and whether it worked for them. Cheers.

Edited by Scoox
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Rotating the flat bars gives you much less adjustment than with risers so you're just limiting your options, plus they just look really shit. You need a ridiculous amount of rise on a mod anyway, makes sense to share it out between bar and stem rather than a 2ft stem and flat bars. Plus they just feel nasty, regardless of the set up, blindfold me and I'll feel the difference.

5a9ad2a077b35__86.thumb.JPG.af8213c1b34e3dfc5f1b27c9e4ced9d8.JPG13464.jpg.1c7bb3a2ddf6024d33030e0dde5a7a55.jpg

It just looks stupid.

Edited by LEON
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I'm amazed no one's experimented with bike geometry more...if you need a 2ft stem why not make the frame reach longer and with a steeper head angle to allow a shorter stem? It's not like comp riders ride much variation so even an 80 degree (or more) head angle wouldn't be a hindrance. 

It might ride like shit but until someone tries it who knows? I know longer stems are good to get the bars higher but that can be fixed with a taller headtube. It'd look odd as hell but might ride amazingly well for comps.

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Function vs looks. But I would go as far as to say a downsweep would feel better than an upsweep. There was a rider who ran his bars upside down. Ergonomic keyboards are convex not concave. Most gym machines designed to pull towards the chest have either vertical grips or down-pointing grips. Handlebars with downward pointing grips doesn't mean you need a crazy long stem though, it just means the bars need to be bent downwards near the ends, so the hands are more comfortable, something like an ez curl bar. Here are some examples of gym equipment that uses a downsweep:

images?q=tbn:ANd9GcTAIgkQfaZPrG-heJ_mdcCimages?q=tbn:ANd9GcQzpOJWzJhGfseztl07QDu3276.jpg

Edited by Scoox
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Good point that riser bars produce a rise. Another advantage of raiser bars is that axial forces are greater which reduces torsion near the clamp, reducing the chances of snappage.

Some crazy motorbike handlebar angles here.

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None of those machines really involve you moving around the machine itself though, whereas you do with a bike.  Your body position from preloading for a gap is totally different to your body position when you're at full tuck on a big sidehop.

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18 hours ago, Scoox said:

LOL yes it does look a bit funny. What are you using at the moment?

I don't ride mod. 26" street with a pretty mtb looking 90 x 10 stem and 2.5" rise bars. Like Ali said, if a frame needs so much stem then maybe the frame's not right. Same can be said for 24" bikes, to a lesser extent though, I hated that I needed 35mm of stackers, a 35deg stem and huge risers but an even longer headtube would look even worse. I think the Skye is one of the best looking 24 bikes for that reason, it doesn't need much height in the front end.

Edited by LEON
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Maybe a slightly longer frame, at least for me. Riders come in all shapes and sizes—so should bikes. Mark has a good point about the gym machines. Regardless of whether it's flat or riser bars, I find generous backsweep and gentle upsweep to feel a a tad nicer.

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As someone who spent years competing with flat bars at a pro American level back in the early 2000s:

 

There is is a certain feeling with flat bars that sucks a big one.  Ollllld schooool... tired. Flumpy.

 

Big question - have you ever ridden trials?

 

When you do a monster gap , tap, hook, you open the possibility of hitting your thighs really really hard with your handlebar , especially if things don’t go as planned.  I have bruises from my arcade bars, which have a monster rise. If I had a big dick stem with flatbar I’d be bruising myself every time I ride.  

 

You lose vital body space. Imagine a ridiculous wheel hook, or putting your front wheel on top of a very high object- where your bike is almost vertical. With a riser bar you are allowed to get your weigh 1-2” more foreword in this situation which makes all the difference. Big dick stem and flat bar pushes you back, no cockpit space. 

 

Trials started with flat bars at a time when risers were crappy azonics that snapped all the time... risers have made leaps and bounds in geometry and strength, I can’t imagine anyone going your route- nothing stopping you yourself from doing it.  

 

Wont work as well and you will look even doofier than Trials riders already do, if you’re fine with that go for it B)

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