Rocket-Sauce 

This looks.... familiar.

https://www.cyclingnews.com/news/is-...Lg__1ITPQZzPUI
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jethin

Don’t ride your bike over big things. Problem solved.

RCMoeur

Been there, rode that. With a 38-tooth Perfect freewheel.

GullyFoylesbike 

Ugh I want one so bad

vespasianus

This is for mountain bikes. It will help.

RCMoeur

The triple-pulley Suntour derailleur, or the big ol' freewheel?

(starts rummaging through parts bins)

nlerner

Triple pulley with a clutch for 1x? Hmm.

embankmentlb

I think of this as the missing link to the 1x drivetrain to accommodate cassettes of unlimited size.

GullyFoylesbike 

The Suntour, but also oh God no I already have so many cool old RDs that need homes and nowhere near the space for all the bikes

C9H13N 

When I first saw that Shimano drawing I didn’t notice the 3rd pulley and I thought they were just moving the pulley cage back to where it was meant to be.

scarlson 

This thing looks like the love child of a MounTech and a three-pulley LePree.

cudak888 

I'm so glad I'm sticking with IGH hubs whenever I can now.

All these innovations and it's still an RD that can't shift when stopped.

-Kurt

vespasianus

I agree. The derailleur is a thing I would love to see go.

repechage

I seriously considered a Schwinn with a Suntour S-1 rear mech, the return of the Nivex before Jan Heine.

Schweinhund

Oh crap, don't give partszilla the idea to come back out with whatever that forward ratchet system they used in the 70's "shift while you're not pedaling system"

cudak888 

God forbid, that's crap too. Plus, it still can't be shifted at a stop, only when coasting. A problem looking for a solution.

I'm not against derailers, but for the amount of overengineering that the technology has had thrown at them, you'd think we'd see a bit of IGH innovation too. I'd love to have a selection that's not limited to slip-prone Nexus 8s, infamously trouble-prone Alfine 11s, and Rohloffs that are unaffordable and require one too many cables.

-Kurt

TiHabanero

In all the years of mountain biking I did, not a single time did I hit something with the rear derailleur. Just don't see the idea of ground clearance as a valid design idea here. Sprocket size, no question about it. This design is a nice nod to Sun Tour as it validates their original idea by copying it, and no doubt making it better.

As for IGH, they are kinda like bents, those who have them snub those that don't. Too bad, as they really are ingenious, just not for me as the weight penalty is more than I am willing to accept.

cudak888 

It'll probably have less friction in it than the Shimano unit, but it still peeves me that for all the efforts to improve derailer design, Shimano's approaches have never been that precise about improving chainwrap with upper jockey wheel positioning. I've always felt that sprung upper pivots with B-position screws don't make enough difference, and - with exception to some really large freewheels - make very little difference at all. Trying to effectively wrap the small cogs is a much tougher task, but it also means crisper shifts on the part of the cluster where many RDs tend to get sloppy, and a better spread of the forces from the rollers on the weakest (due to teeth count) cogs.

Oooh. Lightweight IGH hub...that's an interesting concept too.

-Kurt

scarlson 

Yeah, weight has always been my concern with IGHs too. Some of them feel like a cannonball when you are lacing up the wheel and hefting the thing around.

It would probably require a lot of engineering to make a lightened IGH. Gear teeth would still be steel, but the centers of the gears could be aluminum. Mating the metals would be a lot of work. Or else doing extensive machining on the steel gears before hardening, to remove all unnecessary metal - instead of solid wheels, the gears could be in the form of spoked wheels. Still a ton of work! And diminishing returns as the gears get smaller.

RiddleOfSteel

We just need someone to figure out a single speed CVT setup and we'd be good to go. Super simple. Totally.

Otherwise, IGH should become IGBB. Light wheels are kept or improved, gear weight is centralized, and there really isn't a size limit to the transmission in that area, which would allow one to build it pretty beefy. I know Pinion has a 2-speed setup there and many E-bike companies run "mid drive" motors in the area, so it's not new ground or new thought, just "bumping" the thread of ideas.

scarlson 

Two speed? Pinion's got 18 speed in there! Doesn't retrofit to anything, though. You need a custom frame with a big housing, and it's bulky. The way it works reminds me of a cross between Citroen 2CV gearboxes (concentric shafts) and Eaton Fuller truck gearboxes (ranges and split gears).

Schlumpf's "mountain drive" is a two speed that fits in a normal BB.

RiddleOfSteel

Oof, thank you for the correction! I agree, that thing is bulky--the Q-factor is astonishing. If that could be done to allow a road crank arm set of any sort to bolt up and have its standard Q-factor, I think that would be huge.

P!N20

Who’s Shinano?

Schweinhund

That company thats just a jump to the left of the name brand

cudak888 

I dare say one could try starting with an AW. I wonder how much weight could be shaved from the planet cage. If necessary, a new design with as much material possible removed with air gaps filled with aluminum press-fit inserts to prevent twisting. The driver and ball ring are also heavy components; might be possible to mill out some material from the driver.

Ball ring is next to impossible to modify as-is, but I can see a design with a smaller diameter pawl ring in steel on an aluminum carrier with a press-fit bearing raceway.

-Kurt