[him a layin]

1-down, 4-up seems to be the more common shift pattern, at least on (most of) the rice burners and the himalayan. admittedly a limited exposure. personally, i preferred the all-up pattern on my H1. but i wonder, is 1dn-4up really that common, and why? does it confer some benefit i'm unaware of?

[Richard230]

I think many small Japanese bikes during the 1950's and early 1960's used a rotary system with neutral between first and top gear so that you could shift directly from top gear (typically third or maybe fourth) into neutral and from there into first gear. That was likely a useful system when riding in town from stop to stop. Not so great under most other riding environments. Eventually, manufacturers standardized the current shifting scheme to keep everyone, and especially riders, on the same page when moving from bike to bike. This was quickly followed up by government regulations standardizing the 1 down, neutral, 2nd and all taller gears up system.

[DaddyJack]

Had a '72 Moto Guzzi 750 Ambassador many a year ago, right side shifter, one up, two three four down. Quit riding in '87 or thereabouts, just started again a couple months ago...on the first 1 - 2 upshift out of the barn, I still try to shift on the right now and then.

[AzCal Retred]

So if you had a 'Guzzi, a Royal Enfield, a Honda and a Hodaka you would have it all! 

[DaddyJack]

Did own a Honda, a Dream 250, in the ancient past, for a couple months maybe. Wish I'd kept it, but I wanted to go fast then. A Wombat or Combat Wombat was on my "ooh, ooh!" list, but I never made it happen. Had it all less 25% I guess.

[axman88]

is 1dn-4up really that common, and why? does it confer some benefit i'm unaware of?

Putting N between gears, deliberately making Neutral more difficult to access, makes it less likely for a rider to find themself powerless while in motion.  Downshifting, from an unknown gear ratio, will never leave one in Neutral, like "N at the bottom" could.

If one inadvertently half clicks into N, on their "N in the middle" shifter, while wanting 1rst, another downward stomp is faster than the foot reposition plus upward click required from "N at the bottom".

Also, when starting off after sitting in N at a light, "N in the middle" makes it almost impossible to inadvertently start out in 2nd by lifting twice.  1rst is the other way.

I don't see much difference between "1 down, rest up", and "1 up, rest down", but standardization does seem desirable.  Apparently, at one time, there was quite a bit of variation in layout.  http://www.dansmc.com/gearshifters.htm