Pinion sealed gearbox offers an alternative to those darn derailleurs

Its hardly the first, SR Suntour do the 9 speed gearbox in almost exactly the same fashion....

I love the idea, but I guess it will come down to how heavy a bike is using it. As pointed out above, the frame and pedal infrastructure would be quite different (no cassette etc...). It might be possible to replace some of the frame too by using the gear case as part of the structure. Maybe this wouldn't be used by pro racers, but for commuters and weekend warriors the ease of maintenance and convenience might win through.

Would be nice to know how this compares to something like the NuVinci CVT transmission.

"not all of them have axles that are strong enough for multi-terrain use,"

The Nuvinci has a solid axle. Plenty strong.

"they add revolving weight,"

Near the center of the hub, where revolving mass matters least.

"and that weight is added in the back of the bike – not low and in the middle, where you want it."

I don't see how the center of a hub is any higher than the bottom bracket, especially since the Pinion extends above the BB.

"The multiplication of three by six ratios gives 18 real ratios spaced in even, ergonomically ideal, steps of 11.5 percent."

The Nuvinci is ergonomically ideal because it has infinite ratios. Even owners who don't like the weight will attest to that. You can always find the perfect gear, not just something close. Also, consistent gaps aren't optimal. The thinking has always been smaller gaps in higher gears and larger gaps in the lower gear range.

Heavy or not, still sounds good to me. Fiddling with gear changes is a pet hate ... anything that simplifies the process would be welcome. Didn't somebody invent an 'automatic' bike gearbox a while ago though? Just pedal and it changes up (or down) as the needs of the bike change.

I have a Sram iMotion 9 hub and rarely go above gear 6. I think a 9 (3x3) or 12 (3x4) gearbox would have been more relevant, lighter and cheaper. Shimano have an 11 speed Alfine, and Rohloff had the previous record of 14 speed.

Rohloff Speedhub

Superior in every way.

omg its not weightless! wharever.

some others are fragile! yes...others.

lets see one in "plastics with silicon bronze bearing surfaces for liwest lowest friction and weight. perhaps a 3d printer expert can program one up.

me. i want one that has edrive incorporated and can hanfle regen. lacking that..one that is fast detatch.

all we need is a 3d printer and the file..

(6 lbs!)

no mention of cost

looks like about $500

wle

Fine for a commuter bike in Holland where there are no hills and the lack of cables might be viewed as advantageous. This is a good example of design engineers starting with a project before they fully understand the problem and what users actually like and do not like with current solutions. The Italians have been producing pre-stretched cables for decades that greatly reduce and needed adjustments and the shift lever mounts often include tension adjustment mechanisms.

This design still makes use of the chain which is the one item that the average commuter would like to have go away.

Walt, type at a slower speed and put at least some effort into observing the preferred rules for spelling and grammar.

Beyond that criticism I would like to see someone do a competent engineering study comparing the various CVTs, belt drives, transmissions, along with costs. BTW, a few more ponds in a transmission is really irrelevant if you just add a bigger battery for the front wheel motor. I have used bikes for around town transportation for over forty years. I do not care if the whole bike weighed three ponds wet, having some extra push from a pedelec is worth it.

Oh, to return to the days of yore when all we had was Sturmey Archer's 3 and 4-speed hubs. Simple, safe, cheap - as opposed to the 'unsafe and any speed' derailier contraptions they force on us today.

Literally a go back to the past!! which means maybe the bicycles are "improving" their gears

I suspect that this transmission has more friction than a good derailleur transmission.

Love it and would opt for the belt drive for sure. If I can stand on it and apply max pedal power without breaking it (200lb of mostly muscle between my ears) I would trade the additional net weight (maybe 2 to3 lb) as compared to derailleur, cassette, etc. Nothing like the sweet action of German gears and bearings.

As with all issues regarding energy use or conversion it is a matter of efficiency, cost and versatility. This solution have been on my wish list for many years but now I think that an electric generator - supercap - battery - hub motor(s) is the optimal driveline when using modern high efficiency power electronics.

We look forward to a "Shaft-Drive" version! ...Why not?

hm, seems quite strange since there is already truvativ hammerschmidt or schlumpf dual speed chain wheel...I cant see strong benefit, as there is still rear chain guide :-(

I bought oldschool Sturmey-archer X-RF8 which is fine, see

One of the weaknesses of a chain/derailleur is gear range duplication. A dedicated cyclist will build their own rear gear cluster and choose their front chain wheels to customize their shift points and limit ratio overlap.

The second major weakness of derailleurs is seen when on tries to shift in high torque circumstances such as honking up a hill. Even when the best riders and mechanics tune a riders bicycle it's common to for the chain to slip 5 to 10 gear teeth or throw the chain completely. If the chain gets bound up behind the rear gear cluster and spokes or the front of the gear stack and the frame, the rider is going down and there's not a hell of a lot that the rider can do about it. I broke an ankle from the sudden impact of a chain jamming. That was during my freshman year in high school when I rode an average of 70 miles a day.

The gearbox concept eliminates those problems, but I have to wonder how precisely, quickly, and smoothly they'll complete the high torque shifts. Since I can no longer ride a conventional bicycle. The gear box concept would be ideal for hand powered bikes.

re; Alastair Carnegie

Shaft drive bicycles have two high friction gear sets. I would rather drag a meter wide parachute.

How does it compare to a Schlumph drive?