I wanted to remove 5cm but could not with the stock bar taper. I also added a couple pedal washers and that made a huge difference.

Glad you made the bike more comfortable to you but, I'd be concerned about not having the pedal threads fully seated in the alloy crank, especially ones that look quick release. Perhaps find a bottom bracket/crankset with a wider Q factor?

So did I. I took the bar to my neighborhood metal shop and within minutes they cut 2cm from each end of this 580mm wide bar, narrowing it down to 540mm. I paid $0.90 for their troubles.

Nice. I trimmed the bars on my Bike Friday about 4cm just to make it less cumbersome to carry up the narrow stairs of our basement.

Looks like you're building a mini rocket. Are those Assioma power meter pedals? How does the Zizzo compare to your 700c bikes?

Total width of the handlebar = 44cm. The pedals are basic quick release MKS. The nice thing about these is that they will fit both the MKS road pedals and the Zizzo quick release flat pedals. I have not done a back-to-back test to 700c road bike, but I think the Zizzo is 1.0 - 1.5 mph slower. It's those long folding bike cables hanging in the breeze.

Yah, full pedal thread engagement is ideal. Typically, the first 5 threads of a bolt carry the majority of the load. With two 1.5mm washers for a total of 3mm, there are 5 threads remaining. The washers need to be steel material. I'll put them on my routine inspection list.

I was cool weather today. When I departed in the late afternoon it was 1C. The lobster gloves did not give me any problems in the bike cockpit. Some warm soup midway helped. 30 miles today and the handlebars are a keeper.

Love the handlebar setup. Be careful over potholes, railroad tracks, etc., though. The amount of slender tubing between the headset and the bars and the prospect of having your full upper body weight on the forearm pads over jarring road surfaces looks like a material engineer's nightmare.

I agree. I can't tell if that is a square taper crankset or not, but if it is, that my be a low cost way to change the Q factor. That would also change the chainline, so that could be an issue.

I wanted a narrower Q factor on my heavy duty touring bike by about 10mm, I used a shorter bottom bracket spindle than ideal. My chainline is off by 5mm, but it is on an IGH bike so that is not much of an issue.

I removed one washer from my clipless pedals, leaving just one. I had been feeling slight knee pain in the same spot on both sides when using clipless shoes with two washers. After a 40-mile ride yesterday, I think the issue is resolved. It’s amazing how such a small adjustment can make a big difference. For flat pedals, I use two washers.

Getting better and better!

I'm not worried about the force on the forearm pads as those are centered over the flat bar. But high down or up force on the aero bars is another thing. But usually you won't do that.

I wanted a brake on my aero bars in case something jumps out in front of me, easy to do, I just got a mid-cable/interrupter lever and mounted it left front on the aero bars, for the front brake (between the flat bar lever and the v-brake). Those levers are usually short-pull for road bikes, but it works fine on my long-pull v-brakes as the wheels are super true and pads adjusted close, and I like the added mechanical advantage when holding the bike at an uphill or downhill stoplight.

Right front on the aero bar is a small bell.

I haven't shortened my 58cm bars yet as I lack the real estate to do so, interference with flat bar stuff and the aero bar armrests. The aero bar forearm pads are a bit too close together for me, even on the widest setting, but I have a new set with flip-down rests that is wider. But I want it mounted 75mm higher than the flat bar mount. They make risers that would fit, but not approved by Profile, as they are narrow, and my only guess is, the arm rests would then put too much side torque into the risers and base, that's my guess why Profile does not approve for that aero bar. I will probably do some kind of double-stem-clamp (dogbones) to raise the aeros, and with flip up rests, might narrow the flat bar. I might need a different flat bar because the taper is so slow on the OEM Dahon one, can't clamp anything there. But I ran across a bike friday H bar used, didn't buy it because it was too narrow. I used to ride a road bike with 40cm bullhorns, but that's too narrow for me these days for best comfort.

My aero bar is also my drink bottle mount, Profile makes both. That's especially nice as the stock Dahon bottle cage location, the cage would constantly get bent from my foot hitting it getting on or off, plus the bottle leaks when horizontal like that. I really like the bottle on the aero bar.

OP, are those aero bar cam levers backwards? Or just not locked down?

The cam levers are locked. They lock in the downwards position. I just purchased another set of these for another Zizzo. For a Zizzo you need the additional 25.4mm split shims on their website and then you will need to make some additional split shims from:

Aluminum Round Tube: 6061, 1 in Outside Dia, 0.035 in Wall Thick, 6 ft Overall Lg, Mill, T6

As I will need to make more of these for the new bars. I will make from a 6 ft piece I purchased.... let me know if you need some and I will make and send to you.

Thanks for the offer! I had considered making some shims from copper pipe, as the new aero bars I have are sized for larger bars but are missing the shims for smaller bars (got the bars cheap at my LBS that has excellent deals on stuff like that). But first, I need to find the proper flat bar; I need either, a wider center section 25mm without taper, or a more rapid taper/step down to 22mm, and then buy the dogbones accordingly, to raise up the aero bars alone. Actually, before that, I should buy a new handlepost; I love the tapered steel old Dahon one I have, perfect height (for the flat bars) and more durable and no squeaks like the adjustable height ones, but, the handlebar clamp does not "open up", it's like an old road stem, so need to take half the parts off the bar to slide the handlebar out; I want the new style clamshell opening top clamp, in order to be able to quickly and easily separate the handlepost and bars, if needed for travel packing. I'd prefer a one-piece handlepost, which they do make, but as tall as my current post, that may be more difficult. THEN, a flat bar as noted to match the post clamp size, and then dogbone clamps to match the bar (these would grab the flat bar at wide points, as the aero bars clamp very close to the handlepost, so can't put the dogbone clamps there), then a short piece of handlebar clamped in the other end of the dogbones, and the aero bars clamp to that inboard of the dogbones, with shims if needed to attach the new aero bar. These little mods can be surprisingly complex. Fitting the 2X crank and FD to mine was tricky, had to do some custom fitting, but well worth the effort. Raising the aero bars will be worth it, so I can spend more time there, taking the pressure off my hands, but still have the flat bar lower for good standing climbing.

Where do you fit your front light and bell If you have shortened the handlebar? There doesn't seem to be enough space to attach them anymore. Be careful in Japan, I've seen people get ticketed by police doing traffic stops for bicycles for not having the lights.

I haven't shortened my flat bar, but that is a valid point as there is no space for a light with the aero bar clamped to the flat bar. I put the light on the nose of the aero bar, plus then it's not shadowed by anything in front of it. I carry a light with rubbery strap attachment, usually lives in my trunk bag. Before getting that, I also have a big flamethrower of a light, two beam with separate big battery, the light clamps same on the nose of the aero, and the battery can velcro to the aft part of the aero or go into my jacket pocket.

My bell is on the right front of the aero, mid-cable brake lever is on the left front of the aero.

But for lights or bell, if no aero bar, those can also mount to the handlepost or vertical section of a conventional stem. I did that with the bell on my road bike. A light, need not be immediately at hand, can also attach to the top deck or sides of a front rack.

Be careful of "flamethrower" lights if you go to Germany, legally you need a light certified for German regulations StVO, which require a cut off above the horizon so it doesn't blind oncoming traffic. Although I'm not sure anybody enforces since all the stuff on eBay and Amazon from China are not certified. And blinking bicycle lights are not allowed.
The German lights are actually great because you really don't get blinded by the other cyclists unless they have the Chinese lights or don't install them correctly and point them above the horizon. The B+M lights are great because they're rechargeable, and can act as power bank for your phone in an emergency, don't sag or change position on the handlebar, fairly bright as advertised.
You can tell if it's German certified by the wavy logo and a certification number embossed somewhere on the plastic body.

I'll look the next time I pull out my tacklebox 'o lights. It's a chinese made light off amazon, so I'm sure not certed for germany. Most of the time, any light I am running is on lowest setting, because I'm going slow, and they're also angled low for the same reason. Regarding high-angle cutoff, I may do something on that with aluminum tape. I do remember driving in germany in a borrowed company car; Z-beams, headlight adjusters in the cockpit, and this was a relatively cheap car, the first gen baby benz 190 with vinyl seals and manual everything, I loved it for its simplicity, and it still drove perfect with 300,000 km on the clock. Great car.