Doesn`t this cable routing relate to an old hand signal law for bicycles in the US? I`m from Australia so mine is on the right. I live now in Japan and they are on the right here too.

FB on the left... is it a US thing?

Owned more street and MX bikes than I can remember and it's never even crossed my mind to think about which hand or foot is doing what when going between riding something with pedals or an engine. Thinking about it would cause problems.

If anything, you need almost as much sensitivity and control with your left hand as the right if you have a background on motorcycles since the clutch isn't an on-off switch like a lot of people tend to treat it as.

The reason I like to run my front brake cable to the left brake lever is because my left foot is my dominant foot and I have found that it is more easy for me to come to a stop using my left hand. I also ride a motorcycle and I never get confused, even when faced with panic stops.

Also, I still favor downtube shifters and I am able to shift the levers with greater ease using my right hand.

The shifter on a motorcycle is actually operated by the left foot and the clutch looks like a brake lever and is on the left hand. So shifting is done on the left side. The rear brake is foot operated by the right foot, so braking is done on the right side.

The throttle (accelerator) is a twist grip on the right hand, so when slowing down you often have to modulate the front brake with the right hand while simultaneously "blipping" the throttle to ease downshifting. One or two fingers on the brake lever the rest curled around the grip.

Your preference makes sense in the context of braking and shifting simultaneously with different hands, but I guess motorcyclist are used to downshifting and braking at the same time time with the right hand so that feels more natural to them.

From a dirt bike perspective....

Back in the dark ages when Euro bikes rules [Husky/Bultaco/Maico/CZ/etc.] they all shifted on the right. Theory being that your right foot balanced your left hand [clutch]. Right hand brake....left foot brake. Makes sense to me. In fact if you stand up and raise you right arm and at the same time your left foot, it feels very balanced. Right arm/right foot takes more effort.

Jap bikes came along "backwards" [left shifting] and screwed thing up. Now people are use to right/right...left/left but it just doesn't feel correct to me.

I've been a motorcyclist for 35 years and as many motorcycles, and close to 20 years of serious cycling. I run my bikes with the front brake on the left like most people do. Switching between moto brake and bike brake layout has never been a problem for me.

But on motorcycles, switching between left shift and right shift is not so easy for me. Most of my motorcycles have been left shift and on the right shift ones I sometimes forget and try to brake with the shift lever. When I was looking for a vintage Spanish trials bike a while back I found a Montesa because that era's Bultacos had right shift (and Ossas are unusual in the US).

Thumbs Up!

Due to witnessing so many over the bar head dives we were instinctively and instructively learned to use rear brakes first then apply your front brakes so having the rear on the right worked just better. I ride motorcycles too and in the case of motorcycles it is advised to use your front brakes due to better stopping power so going from one to the other works just fine. Use right hand to brake.

right hand front brake.

It's funny, I have been riding motorcycles and have raced enduro for years and still ride now as well as riding and racing bicycles (MTB before and now road) and never had an issue switching from one to the other. It never seemed weird and I never considered changing it.
I get the logic to it and all though.

Left, that’s how I started riding as a kid, and it is what I’m used to, otherwise I don’t imagine it matters much.

All of mine are on the left, but I did know a guy that was incapable of adapting from dirt bikes, so his went on the right. I always made fun of him for it (not because of preference, because he literally could NOT ride with it on the left).

FB to left lever.

But, I rented some mountain bikes in New Zealand a couple years ago. Kept skidding the rear tire in the Port Hills outside of Christchurch until I caught on that I was squeezing the "wrong" lever. No problems once it was in my head.

Two weeks later in Queenstown, the guys at the bike shop switch the cables back to the American way before I picked up my rental thinking they were doing me a favor (which, of course, they were). But I had to spend another hour re-learning which lever to squeeze.

I think I would have a harder time with the switch on a road bike because in addition to applying the brakes I am so used to reaching into pockets, zipping up/down jerseys, taking pictures, etc. with my right hand while applying front brakes with my left.

Right hand front.

This is an interesting perspective I had never considered.

My first road bike, a French-built Follis, came the right brake lever set up for the front. I've kept it that way, even though all my other bikes over the years have been set up the opposite way. I don't seem to have any problem adjusting to either mode.

My Follis is turning 50 this year. I've ridden that bike - at least the frame as well as the very same brake levers and brakes - for almost half a century.