[crank1979]

That looks great. I'd love to give it a try and compare it to my Pinion bike.

I'd like to see it working on a dual link bike like a Pivot. Maybe also wireless shifting.

 

[dir-T]

All that extra weight and complexity to address what problem - the chance that the derailleur cage may hit a rock? I'll just keep picking good lines when I ride.

 

[watermonkey]

This is absolutely awesome. As a left handed person, my inclination has always been to lay my bike down on the drive side, but for obvious reasons, one doesn't. If I had this, I'd throw my bike down onto its drive side, with joy, every time I dismounted it. I hope this guy make millions. Good luck to him.

 

[Sparticus]

Awesome! I hope the inventor becomes a multi-billionaire from his creation.
=sParty

 

[rockcrusher]

This is really amazing. What I like the most is the fairly robust mounting point for the shifter part of the drivetrain, which as we all know having that device out of alignment just a small amount means shifting performance will be reduced for sure. I also like the huge amount of wrap on the cassette. This should lessen wear on the cassette plus give it better performance in bad conditions (if you have ever ridden a really muddy race you will know what I mean).

I feel like the missing thing here is making the rear cassette fixed and adding the freewheel action to the crank, which would give it the same benefit of shifting while not pedaling making it really close to a gearbox in its ability to shift while coasting, though I would take this as is too.

I think moving the derailleur out of the way is minor benefit. The bulletproof mounting of the shifter and the cassette wrap seem much more important.

I appreciate that for my eyes this is something completely new and when was the last time someone reimagined the eternal rear derailleur?

 

[Sparticus]

I appreciate that for my eyes this is something completely new and when was the last time someone reimagined the eternal rear derailleur?

Right. We've finally eliminated the pesky front defailure, now let's optimize the rear derailleur.
Either that or develop a bulletproof, low friction, lightweight gearbox or IGH.
Meanwhile this thing looks sweet. Well, except it appears you have to accept the high pivot.
I'm not sure I want that.
=sParty

 

[chucko58]

Meanwhile this thing looks sweet. Well, except it appears you have to accept the high pivot.
I'm not sure I want that.

It looks to me like the idler is more to help package the system, making room for the tensioner. The fact that the idler enables a high single pivot rear suspension is a bonus for people who like high pivots.

I suspect the idler could be relocated or omitted entirely with a different layout. The derailleur location looks ideal for a short-link 4-bar (e.g. VPP or dw-link). It looks like it would be hard to package for a Horst link.

 

[acer66]

While this is way over my head I always like people trying things out and I hope he succeeds.

 

[uzurpator]

Awesome! I hope the inventor becomes a multi-billionaire from his creation.
=sParty

As a self professed hater of 1x I wholly agree. This is actual progress. High pivot, good chain tension, large chain wrap on both chainring and the cassette.

 

[Sparticus]

As a self professed hater of 1x I wholly agree. This is actual progress. High pivot, good chain tension, large chain wrap on both chainring and the cassette.

Hey uzurpator, I'd love to get your opinion on a question I have about the swing of the derailleur on this Lal bike.
Obviously the cogs go from smaller near the outside of the hub to larger near the center of the hub, so the "cone" shape of the cassette widens as we move toward the centerline of the wheel's plane.
Would it make more sense to mount the der on the swingarm's flat brace between seat & chainstays so that the arc of the der more closely parallels the angle of the cassette's cone shape?
That is, move the der's mount 180º from where it is now.
Does my question make sense? Hard to explain, maybe.
Anyway thanks in advance for your insights, assuming you have any. I appreciate your ability to see through this kind of stuff.
=sParty

 

[cdalemaniac]

Nice thinking outside the box, but besides needing a frame made for this system, I also see a problem with having bigger calves.
That chain is getting a bit too close to the leg for comfort….. what if you wear a bit looser fitting long pants? Push the bike into a right turn berm?


Sent from my iPhone using Tapatalk

 

[socal_jack]

Nice thinking outside the box, but besides needing a frame made for this system, I also see a problem with having bigger calves.
That chain is getting a bit too close to the leg for comfort….. what if you wear a bit looser fitting long pants? Push the bike into a right turn berm?


Sent from my iPhone using Tapatalk

Yeah was thinking this bike could really use a clutched derailleur watching that chain whip around. That's like going back 10 years as far as that goes

 

[Darth Lefty]

This seems good in itself but that alone won't make it successful. If it proves out then the big challenge is displacing existing stuff that is well entrenched.

The pantograph has to follow the cassette, there are no games to play with the chain tension pulling the upper idler further away to make the pantograph smaller like with regular derailleurs. I bet right now he's got a longer chain run than he wants from the cassette to the idler in high gear.

He's got a lot more of the chain wrapped around the cassette and I wonder if that's a problem for the shifting.

I've been trying to think of what it might enable for suspension kinematics and it feels like it's still a high pivot with an idler. (This year's entrant being the Orbea Rallon). This is all about the lower chain run which is not really under the same kind of tension, just enough to take up the slack.

Clutch... hmmm. Would a clutch in the tensioner interfere with the suspension? Or is it just a widget he hasn't added yet because he got to a point he needed to publish. EDIT: he's got his tensioner hooked up to a spring and damper in the down tube. And he's gone T47. That's the first thing here that would keep you from just adding this to any bike adding the appropriate mount to the swing arm. At first glance it looked like it all went onto the ISCG tab.

 

[Urnso3]

All that extra weight and complexity to address what problem - the chance that the derailleur cage may hit a rock? I'll just keep picking good lines when I ride.

The importance of protecting your derailleur varies by rider style and terrain. I broke 5 my first year switching from BMX bikes to MTB. It’s been awhile since I’ve tore one off but still find myself replacing almost yearly due to poor alignment.

 

[Cedric Eveleigh]

Hey uzurpator, I'd love to get your opinion on a question I have about the swing of the derailleur on this Lal bike.
Obviously the cogs go from smaller near the outside of the hub to larger near the center of the hub, so the "cone" shape of the cassette widens as we move toward the centerline of the wheel's plane.
Would it make more sense to mount the der on the swingarm's flat brace between seat & chainstays so that the arc of the der more closely parallels the angle of the cassette's cone shape?
That is, move the der's mount 180º from where it is now.
Does my question make sense? Hard to explain, maybe.
Anyway thanks in advance for your insights, assuming you have any. I appreciate your ability to see through this kind of stuff.
=sParty

For context about what I'll say here, check out the arc of motion of the derailleur pulley in a photo on the lalbikes.com main page. There are several factors, including the need for chain wrap on the derailleur pulley, that makes it preferable for the arc to be as it currently is on the Supre Drive.

 

[Sparticus]

For context about what I'll say here, check out the arc of motion of the derailleur pulley in a photo on the lalbikes.com main page. There are several factors, including the need for chain wrap on the derailleur pulley, that makes it preferable for the arc to be as it currently is on the Supre Drive.

-Cedric Eveleigh

Thanks! I'll check that out.
=sParty

EDIT: I checked the vid out again. Should have looked at it harder the first time as it's easy to see that the jockey pulley on the der follows the cassette's "cone plane" perfectly. Thanks again for suggesting I take another look, and best of luck to you. I still hope you become a multi-billionaire from this venture. Your concept is sooo ingenious.

 

[Cedric Eveleigh]

Yeah was thinking this bike could really use a clutched derailleur watching that chain whip around. That's like going back 10 years as far as that goes

The chain tensioner in the Supre Drive has a damper that works very well (same purpose as the "clutch" damper of conventional derailleurs). The folks who have tried the Supre Drive or who have ridden with me say that the Supre Drive is quiet. If you look at slow-mos of conventional derailleur drivetrains, you'll see similar chain motion.

 

[Cedric Eveleigh]

This seems good in itself but that alone won't make it successful. If it proves out then the big challenge is displacing existing stuff that is well entrenched.

The pantograph has to follow the cassette, there are no games to play with the chain tension pulling the upper idler further away to make the pantograph smaller like with regular derailleurs. I bet right now he's got a longer chain run than he wants from the cassette to the idler in high gear.

He's got a lot more of the chain wrapped around the cassette and I wonder if that's a problem for the shifting.

I've been trying to think of what it might enable for suspension kinematics and it feels like it's still a high pivot with an idler. (This year's entrant being the Orbea Rallon). This is all about the lower chain run which is not really under the same kind of tension, just enough to take up the slack.

Clutch... hmmm. Would a clutch in the tensioner interfere with the suspension? Or is it just a widget he hasn't added yet because he got to a point he needed to publish. EDIT: he's got his tensioner hooked up to a spring and damper in the down tube. And he's gone T47. That's the first thing here that would keep you from just adding this to any bike adding the appropriate mount to the swing arm. At first glance it looked like it all went onto the ISCG tab.

I don't think the damper in the chain tensioner causes any sort of significant interference with suspension function.

 

[uzurpator]

Would it make more sense to mount the der on the swingarm's flat brace between seat & chainstays so that the arc of the der more closely parallels the angle of the cassette's cone shape?

It does not really matter how you mount the parallelogram. As long as the guide pulley is within certain distance from the cogs its all fine. Dahon is doing something like this with their Neos but for the most part - it is doing something different for the sake of being different.