Dave Weagle Patents High-Pivot Drivetrain System

Jan 26, 2023 at 9:26
by Seb Stott  
photo

Recently we spotted this patent filed in 2022 by Dave Weagle (yes, that Dave Weagle of suspension-designing fame) for a "sequential adjacent drive assembly". Basically, it's a drive system for high-pivot suspension bikes that uses two chains: one connecting a sprocket on the crank to a driven sprocket above it, which is fixed to the frame on a bearing and connected to an adjacent and co-axial sprocket that drives a second chain. In turn, that second chain drives the cassette.

photo

The concept is similar to a jackshaft arrangement, like the Starling pictured below on the left, but this time both chains are on the drive side of the bike. This means a regular crank can be used (fitting a standard crank the wrong way around with the chainring on the left-hand side can cause the pedals to unthread while riding) and, crucially, means it can also work with mid-drive e-bike motors.

07.04.19. Starling Cycles Triscombe. PIC Andy Lloyd www.andylloyd.photography
Trek Session Photo Kifcat Shaperideshoot

Most high-pivot bikes these days instead use a single chain but with an idler pulley above the chainring, either on the mainframe or swingarm, so that the upper chain line is roughly aligned with the main (or effective) pivot point of the suspension (such as the Trek Session above on the right). Compared to this layout, Dave's design has a few claimed advantages.

The first is chain wrap and reliability. For packaging reasons, many idler-drive bikes tend to use small idler wheels (the Trek pictured above uses an idler with only 13 teeth, but 15-16 teeth pulleys are common). The smaller the sprocket, the more pressure on the teeth and so the faster the sprocket wears out. Dave's design uses sprockets of at least 16 teeth to reduce tooth pressure and sprocket wear. The primary chain (connecting the crank to the first driven sprocket) can have odd-numbered teeth to reduce chain wear, or else use a half-link chain or a belt, which Dave claims could last the lifetime of the frame.

Then there's chain wrap. The patent states that, following best practice engineering principles, the chain should ideally wrap around a sprocket for at least 120° to avoid excessive wear or chain skipping. In order to achieve this with an idler drive, there usually needs to be a lower pulley on the slack (lower) side of the chain, just behind the chainring. These pulleys can be necessary anyway to reduce chain growth in the lower chain span as the suspension compresses, especially for bikes with very high pivot locations or long suspension travel. So while Dave's design looks more complicated, there are the same number of sprockets in contact with the chain as there are in a conventional high-pivot with an upper and lower pulley (three - not counting the derailleur and cassette).

Furthermore, because the sprockets in this patent are larger than conventional idler pulleys, it could be more efficient. That's because as the sprocket gets smaller the angle through which the chain has to bend at each link as it rolls onto and off of the sprocket (known as the articulation angle) increases dramatically - see the graph below on the right.

photo
photo

According to the patent, the total angle through which each chain link has to articulate back and forth as it snakes through the drivetrain is less in Dave's design when compared to an idler with a lower pulley design, which, it says, could lead to less energy lost in the chain pins and so better efficiency - "Engineering all sprockets other than those in the cassette to have 16 or more teeth can provide increased efficiency over typical idler drive cycles which feature slack side and tension side idler sprockets of 15 and fewer teeth."

photo
The patent provides some examples of sprocket configurations for this and conventional idler drivetrains and compares the total amount of chain articulation involved in each.

It's worth pointing out that if a conventional drivetrain can do without the lower idler pulley (as many do, whether or not it's best engineering practice) then the total amount of chain articulation (and therefore power loss) will be less.

Finally, in a conventional drivetrain, the gearing is determined by the chainring; for most 29ers, the most common size is 32-tooth. By using a smaller first-driven sprocket than the two driving sprockets, it is possible to achieve the same gearing ratio with a smaller sprocket on the crank (22-30 teeth according to this table of workable sprocket combinations). This has two advantages: one is to increase ground clearance and the other is to increase the amount of critical space between the tire, the chainring, and the chainstay yoke.
2022 Norco Range C1
The Norco Range goes without a lower idler and seems to function okay with around 90-degree chain wrap.



photo

It's mostly not about performance

When I called Dave Weagle to discuss this patent, he told me that the performance advantages were "less than 50%" of its value". The rest is on the manufacturing side. According to the patent, "packaging issues surrounding clearance between rear tires and chainstay yokes now drive close to 70% of the total time spend developing a new frame model." Using a smaller chainring at the crank, along with elevating the swingarm, frees up valuable space in this critical area. This real estate could be used to make simpler chainstays with no need for complex forgings, carbon moldings, or even yokes. The swingarm could therefore be lighter, cheaper, and stronger.

Alternatively, it could be possible to design bikes with shorter chainstays. This is not something everyone wants, but with a 29" wheel the shortest achievable chainstay length is about 430 mm, and smaller riders might benefit from shorter chainstays to allow them to get their weight over the rear axle when they want to manual. Moreover, the high-pivot design makes it easier and cheaper to vary the chainstay length without having to change the swingarm or the suspension kinematic. So it could be easier to have size-specific chainstay lengths, including very short stays for the smallest size.

photo
The design could work with e-bike motors too, and with many of the same components.

The case gets stronger with e-bikes because space behind the BB is even more limited and long chainstays are more problematic due to the added weight of the battery in front of the bottom bracket. Plus, because the swingarm and main pivot are up and out of the way of the motor, it may be possible to share hardware (including the pivots, sprockets, and swingarm) between e-bikes and regular bikes. This too could help bike companies keep costs down.

photo

How high is "high pivot"?

While some high pivot advocates wax lyrical about the benefits of fully rearward axle paths, the patent advocates a more moderate approach: "By tactically placing the inflection point [that's the part of the travel where the axle path stops moving backward relative to the mainframe and starts moving forward] between 40% and 80% of the vertical rear wheel displacement, as is possible in the disclosed assemblies, a more stable horizontal chainstay length can be maintained."

On our call, Dave explained that he thinks the horizontal chainstay length should be as consistent as possible during the part of the travel used during cornering (40-80% travel), so the load on the rear tire (which determines grip) is as consistent as possible too.

In other words, he's not so much advocating a rearward axle path but a vertical one, especially in the middle of the travel where cornering grip is most critical. Otherwise, he says, if the axle path moves forwards or backward too much, the load on the rear tire changes as the suspension moves in and out of its travel, leading to inconsistent grip. This is simply because the closer the rear axle is to the bottom bracket, the higher the percentage of the rider's weight is supported by the rear wheel.

The introduction of 29" wheels and lower bottom bracket heights, combined with the fact that the main pivot needs to be a certain distance above the BB for optimum pedaling performance, has meant that the axle paths of non-high-pivot 29er bikes have become increasingly forwards in recent years. As Dave put it, this design just allows us to have axle paths that were common in the days of 26" wheels, but with a bigger wheel and a lower BB.

The chart opposite shows the axle path of the "mid-high pivot" 2022 Trek Session; it's roughly vertical overall, with an inflection point at around 50% travel. Alongside it on the right is the axle path of the idler-free 2018 Session 29, which has an overall forward axle path. Note the horizontal axis is magnified, but with the idler-free bike, the horizontal chainstay length will shorten by as much around 20 mm as the suspension compresses, which will shift load towards the rear wheel.
Trek Session Axle Path

It's true that the front wheel has a highly rearward axle path, meaning the front center shortens as the fork compresses, and this means that to maintain a constant weight distribution when the front and rear suspension compress in unison, you'd actually want a forwards axle path. But Dave points out that the fork and shock rarely compress in phase, so you may as well have the most consistent chainstay length you can (aka a vertical axle path).

Will it see production?

When I talked to him, Dave wasn't over-selling this idea. "Do I think that 150 mm bikes will be running around with this technology? They could... but I'm not going to sit here and tell you it's going to be some superior riding thing," he said." "It does work and it solves a bunch of issues. It has its small range of places where I think it's applicable and useful... We'll see if it goes to market - I hope it does."

Author Info:
seb-stott avatar

Member since Dec 29, 2014
306 articles

241 Comments
  • 200 8
 Finally a DW link system that sucks going uphill
  • 16 39
flag baca262 (Jan 26, 2023 at 9:58) (Below Threshold)
 are you sure? the higher the pivot, the more drive force from the wheel pushes the wheel forward, cancelling out bobbing
  • 32 5
 @baca262: added drag is usually the culprit on these designs= not great for uphill
  • 12 22
flag baca262 (Jan 26, 2023 at 10:34) (Below Threshold)
 @neroleeloo: you can't say these designs, this isn't the same as either an idler pulley or a gearbox. this would have less drag than a pulley since the sprockets are big and better supported.
  • 4 0
 Ha!
  • 77 41
 Pinkbike! The new home of Drag Queen Story Hour.

That's right folks, you thought it only existed in schools, but Pinbike is the new hot place for grown men to cattily exchange their half-baked stories and perversions about drivetrain efficiency.

Who will triumph? Who will be the King of the Drag Queens?
  • 17 32
flag baca262 (Jan 26, 2023 at 11:28) (Below Threshold)
 @excavator666: off ur meds, huh?
  • 9 2
 @excavator666: If you don't know you can measure friction using 2 pink eyeballs and a phone screen, I can't help you.
  • 14 1
 @neroleeloo: this thing has EBIKE written all over it. It will be great uphill for that reason.
  • 3 0
 Actually looks chain suck friendly Smile
  • 10 4
 @baca262: I was in agreement with you, actually. If people would take the time to look, they would see it's not an idler system.

There could be an article about a balance bike on here though and some halfwit would still trip over themselves to complain about drag.
  • 2 0
 Nice@excavator666:
  • 3 0
 @baca262: Someone fancies themselves as an engineer...You know you want to fix what was never broken.
  • 2 1
 @baca262:

You should ride of those first gen Trek full suspension bikes, to see how well that hypothesis translates to reality
  • 4 0
 Well at least Trek couldn't possibly come uo with a 'tissue paper with scribbles on it" concept from 5 years ago. Good on you DW. Protect whats yours and not get ripped off again.
  • 3 0
 @neroleeloo: Yes has more drag, but can reduce or eliminate pedal kickback, so has some uses?
having worked on similar drives 15 years ago know it will be less efficient but only by 2-3 %
which is less than a dirty chain or other forms of gearbox's
  • 2 1
 @excavator666: lol, took me a while to realize the connection between drive train efficiency and drag queens.
Very well played
  • 4 6
 @michibretz: Basically the same thing as the other Drag Queen Story time except slightly less scary. Grown men, living in a fantasy land and telling fairytales to those impressionable enough to listen.
  • 2 3
 @excavator666: There's a lot of it about.
  • 1 3
 @baca262: not sure why you’re getting downvotes for valid comments.
  • 1 0
 @neroleeloo: drag is like 1% according to Beta lol. But probably worse on this design. Two chains, more teeth, more wrap and more bearings giving resistance.
  • 89 1
 Brooklyn Machine Works had this many many years ago for their TMX and RaceLink DH bikes.
  • 7 0
 I thought of that immediately.
  • 11 0
 That was probably 20 years ago now.
  • 35 2
 Yeah, but their extra chain was on the non-drive side, so it's "different" from a patent perspective. Weagle has made a fortune on patents that are different based on a tiny little detail.
  • 5 0
 tora cycles have similar now too
  • 12 0
 Got to ride the fabled SuperCo Silencer once. Hell of a bike. Ahead of its day at the time.
  • 3 0
 @rideordont: dream bike right there...
  • 19 0
 @Explodo: "Weagle has made a fortune on patents that are different based on a tiny little detail."

This is the essence of modern patents as there are a miniscule number of truly unique ideas. Rather it's building on what came before.
  • 5 0
 @rideordont: I got to ride that at Platekill, that bike was very cool. Also got to see all the old BMW's at Platty back in the day. #platekillbackground
  • 29 1
 As much as I admire Mr Weagle, I'm still on the fence about this patent: Should I decry the absolute ugliness of the US patent system, or should I praise DW for getting a patent awarded for stating the obvious and reusing prior art (AKA BMW's RaceLink) without anyone noticing?
  • 6 0
 exactly, BMW did this. (Brooklyn Machine Works)
  • 4 18
flag jason3559 FL (Jan 26, 2023 at 12:06) (Below Threshold)
 @southoftheborder: oh the struggles of the peanut gallery. Such lament since this posting, in what an hour and a half? Ffs ‍♂️
  • 10 3
 @jason3559: f*ck off, now you're gonna Qui Gon me, stating you have a moral higher ground? I'm just laughing at the nonsense of the US patent system.
  • 2 0
 @Explodo: I thought a patent had to be a certain percentage different in order to be "new"?
  • 8 11
 @southoftheborder: There is not enough real significant advantage in this design for it to be desirable and it doesn't solve any significant problems. This is dead on arrival and there's a reason companies tried similar things and moved on.

DW probably just bored and looking for publicity, Pinkbike gets some clicks, the end.
  • 5 0
 @seraph: The US patent office has a history of just granting whatever to whoever, whatever thebrules are they don't seem bothered.
  • 2 0
 YEAH, AND TRY LOOKING AT "TORA" BIKES...... They resurrected BMW design.
  • 2 0
 @fartymarty: If it was a patent by BMW and it has expired, it is now free for everyone to use. You can't patent it again. Nicolai did something similar, just that the "upper pulley" was a Rohloff geared hub. If the chainring needs to be left, just get BMX cranks (which typically allow you to use the sprocket left and right). Nowadays, if you want internal gearing with a high pivot, Effigear is the way to go. If there is supposed to be a motor involved (so for that subset of people who both need a motor and demand a more rearwards axle path) they probably wouldn't be too worried about the slight increase in drag of a conventional high pivot. Rocky Mountain has a bike for them already.
  • 3 0
 @vinay: not sure if there was a patent as several other (Starling, SuperCo, Peregrine) have done something similar.

My guess is this is for an ebike altho what baffles me is why no-one has done an ebike motor with a gearbox and lose all the crap at the back wheel.
  • 1 0
 @hamncheez: the weagle patent has the chains the other way round (ie the one attached to the cranks runs inside the one running to the wheel)

I'd personally think the layout in your photo is nicer, but maybe the chainline is worse?
  • 3 0
 @hughlunnon: The difference might be that the Tora bike has the idler concentric with the pivot while on the Weagle patent it is not.

I think Haibike have a patent for high idler on ebikes that they don't even use anymore because the motor has shrank enough to avoid it (but thatmay be the reason why there is not high pivot ebike ? Or did I miss any ?).
And with high pivot some brand has a patent for chainstay mounted high idler, so you have to either put it on the frame or on a swingarm if you don't want to pay.

So yeah this looks a bit lame, as if it's a game of finding a niche to get a patent and be hopeful it'll turn into the best solution that every brand wants to pay for.
  • 3 0
 @Will-narayan: idler on the swingarm/linkage is I-track, they made prototype and patented it, I have a craftworks enr that uses it.
  • 1 1
 YUP spot on unfortunately Douche Weasel Design @Will-narayan:
  • 2 0
 @Local717: same.

I rolled up to PKill with a Spesh Hardrock SS (added gears) and clips. I wasn’t gonna ride with clips. They let me rent BMW pedals from the shop.
  • 2 0
 @fartymarty: my TMX is ‘97 vintage one of the last before they went to race link - pretty much zero bob when pedalled shame it weighs as much as Brooklyn bridge so can’t comment on uphill work beyond pushing
  • 2 0
 @vinay: I’ve a BMW TMX and a couple of the nicolai gboxx nucleons - these things pedal flat and the nukes if you have the legs can go up hill with their massive gear range if anything they were under geared so it’s easy to overspin if you are on the smoother down hills
  • 84 3
 These cheeky chancers that go around patenting the bleeding obvious get on my tits a bit
  • 51 0
 It is impossible to read your comment without hearing a thick British accent in my head.
  • 8 0
 @tpfenning: Just needs to be prefixed with "I say Fanshaw...."
  • 4 0
 At my job i sometimes get into contact with patents and patent lawyers sometimes (not Specialized) and it's insane to see what kind of stuff is patented. Right now we are trying to file a patent for a process of welding one object to another object via a process. Thats about as specific as it gets.
  • 12 0
 @Muckal: can we get Taj to do some joke patent designs please?
  • 3 0
 If you run a chain to pulleys on each of your tits, you'll be double drag.
  • 4 1
 @Muckal: If the wheel was invented today, someone would immediately patent two-wheeled, three-wheeled, four-wheeled, etc. vehicles, without the intention to ever actually build one, and we would all end up driving around in seven-wheelers, because nobody els would want to pay license fees… but hey, it‘s all in the name of technological progress.
  • 1 0
 Never forget that Dave Weagle made a Trust fork with 130mm of travel and then marketed it as something that feels like it has 160mm of travel, thus suited for enduro bikes.
  • 1 0
 I can't see DW ever making back the money invested in the patent, let alone any profit on this. I do like DW - the DW LInked Sunday was a beaut and the Atherton bikes similar but this does seem a case of stating the bleeding obvious rather than a patentable invention.
  • 49 0
 Leave it to Weagle to patent something because "it's on the other side" from things that have been done before. That's less a knock on him than on the patent system.
  • 9 0
 Except this has literally already been done before, exactly, by Gack (same Chris Gack who brought 14mm axles to BMX) in the early '00's. I'm struggling to remember the model name of the DH bike. Anyone care to help me out with this?

Interestingly, there's an article that mentions the bike here, but no photos: www.pinkbike.com/news/article956.html
  • 9 1
 @DirtCrab: Yeah...so maybe prior art exists, but in the patent world you can still get a patent if prior art exists if there's some tiny stupid thing that's different..like the extra chain isn't on the non-drive side. To normal people, that doesn't warrant giving a patent because the idea is the same, but the patent world is absurd. I'm glad PB is publicizing this so that all the prior art people can come out of the woodwork and try to torpedo the application. Sometimes, however, it's not who invents it, but who patents it that wins.
  • 7 0
 @DirtCrab: Balfa NR in he late 90s had a similar 2 chains setup
  • 39 17
 Weagle's whole shtick is collecting dumb patents and pretending he's some sort of genius, then collecting money when manufacturers are forced to use his designs because they're just what someone would come up with if they were designing a bike. This specific one is not even new and imo a form of patent trolling.
  • 8 2
 if the patent system was more vague, and allowed someone to say, invent the wheel, and anything from then on that was round was covered by said patent, we would likely still be pushing wooden carts with stone wheels around. lol patents are hyper specific for a good reason.
  • 8 0
 @Explodo: FWIW, the Gack design was literally exactly the same as what's being applied for here (both chains ran on the driveside and were connected via a miniature freehub body, it was specifically NOT a jackshaft bike).

@ neroleeloo: The NR was SUPER rad, but ran on a jackshaft, a la BMW, Superco, etc. Similar, but not the same.

Bickering about whether or not Weagle should be issued a patent for something someone else developed... anyone else getting hcor.net flashbacks?
  • 5 0
 tora cycles are making this already, theres also been a few other prototypes in past I remember having twin sprockets on same side and eccentric bb.
  • 4 0
 @bat-fastard: Thank you, I KNEW I had seen a more modern version of this concept. That Tora speaks to my 12 year old self, and it sounds like the Plattekill chairlift on a cold foggy morning...

ETA: However, they orient the chains backwards of Weagle's proposed use (RWD chain on outside for additional clearance).
  • 3 0
 @DirtCrab: I'm on a darkcycles scarab, very tempted to hang old girl on wall and get a tora, plus they do custom xs for my short ass.
  • 1 0
 @Explodo: Sure, but you can still get sued and the patent won't hold up in court if it's obviously theft of another patent.
  • 5 0
 Would the old Zerode G1/G2 bike infringe on this stupid patent too? Its the same thing except a geared hub is added. Both chains on the drive side, high pivot.
  • 3 0
 Cannondale's Fulcrum DH bike had the extra chain on BOTH sides back in 98. I guess it was natural for someone to patent just the right side if the left was also already taken.
  • 7 0
 @hamncheez: I am not a lawyer but saying 'it's the same, except that it's not' doesn't seem like a good argument.
  • 4 0
 @CobyCobie: Well, Shimano does this all the time. They patent stuff simply to stop competitors from using a variation of their current designs. Most of the patents they get awarded will never see the light of day, even when they could be a major improvement in the real world. Case in the "derailleur in a box" setup they developed for the second generation Honda RN01.
  • 10 0
 I did something similar to this 10 years ago for a crappy highschool project, Surprised the countless other bikes with similar set ups aren't flagging as prior art in the patent office. ep1.pinkbike.org/p5pb8832770/p5pb8832770.jpg
  • 3 0
 @Ben-Brough: Well, Dave's desing does away with zip ties, that has to account for some original development...
  • 1 0
 @primetime4: was wondering if anyone was going to bring this up. Myles used to snap the small chains a lot.
  • 5 1
 @southoftheborder: Ok, I'm also mad at them for patenting the 1 way clutch that is also adjustable and forcing Sram to go from an excellent design to absolute crap from the 2.0 to 2.1+ clutches.

DW seems to get the heart eyes from the masses for being some sort of suspension genius when he really just patents generic stuff. Co-rotating links is his most famous, which is an insane patent and has cause other manufacturers that want to use it to either pay him or make their own stupid patent.

Being able to patent slightly different versions of a 4-bar is pretty silly too.
  • 4 0
 @southoftheborder: .......it's my mech in a box! its my mech in a box, baaaaaabyyyyyy!
  • 3 0
 @CobyCobie: That’s insane that’s he’s allowed to claim this as his idea and actually charge people to use it. I feel like there should be someone stepping in and stopping this. Actually a good scam when you think about it.
  • 2 0
 @primetime4: Yep Cannondale had that second chainset so you could have giant 52 tooth equivalent gearing (pedaling!) without running a giant pie plate chainring 3 inches off the ground unsagged, lol
  • 1 0
 @thenotoriousmic: but.....it is his idea! there is actually HUNDREDS of people at the patent office that would have stepped in had it infringed on someone elses idea. That is literally the entire purpose of the patent office.

I have no clue what you are on about here, besides an overdose of feelings. lol
  • 1 0
 @thenotoriousmic: someone linked the old abp/split pivot article down the page and the comments have a lot of discussion about the very same thing.

m.pinkbike.com/news/Court-Issues-Ruling-In-Split-Pivot-Lawsuit-2013.html
  • 5 5
 @CobyCobie: it literally doesn't matter. first to patent, owns the patent.

anyone before that didn't patent......sorry about your piss poor planning
  • 3 1
 @Mtbdialed: You can be right and still not be in the right.
  • 4 1
 @Mtbdialed: It’s not his idea though. People have been joining sprockets with chains since the dawn of Industrial Revolution. Like @CobyCobie said that’s the just the way to do it and it’s been done before. Stealing someone’s idea, getting a patent on something and trying to scam money out of anyone else that does the same thing is joke.
  • 1 6
flag Mtbdialed (Jan 27, 2023 at 8:13) (Below Threshold)
 @thenotoriousmic: it's almost like you are just in your feels about this, instead of looking at it logically.

DW didn't get a patent on a sprocket and chain, and you know this. He patented a very, VERY specific/novel layout and utilization of said chain and sprockets. What you are saying is that no one can ever get a patent on anything that uses a chain, sprocket or any combination thereof? LMFAO
  • 3 0
 @Mtbdialed: It is very specific, yes, but it is hardly novel. Adjacent sprockets to redirect chain forces has been used in thousands of different applications, so yes it should be very, very hard to patent almost any configuration of a chain and sprocket.
  • 3 0
 @Mtbdialed: I don’t think we’re ever going to see eye to eye on this one but like is said it’s great scam.
  • 1 2
 @hamncheez: novel and specific are basically synonomous.

I think you are saying you have a problem with the patent system, not DW. is this correct? if so, we might have a lot of common ground....
  • 2 1
 @Mtbdialed: They don't mean the same thing at all.

Novel means "unique" or "new" as in "novelty".

Specific means well specified, or well defined and narrow.
  • 2 0
 @Mtbdialed: and even then they who have the biggest lawyer fund therefore wins
  • 1 1
 @hamncheez: in patent law, well defined and narrow=novel.
  • 1 0
 @Mtbdialed: So SRAM's Narrow/Wide patent would be novel/vintage?
  • 2 1
 @southoftheborder: if the tooth profile/retention mechanism is different, yes.

you can't patent the exact same thing whether the patent is still valid, or if it has expired.
  • 1 0
 @Mtbdialed: mine was a tongue-in-cheek comment, but thanks anyway for the clarification!
  • 1 0
 @DirtCrab: We had 14mm axles in BMX in the late 90s.
  • 35 3
 Neat! The chain layout is very similar to my engineering senior project from 2016. I can say from experience that setting up 2 chains was not that hard compared to the other added complexities of the drivetrain setup. I posted a picture in my account if anyone wants to see a shoe string budget "gearbox" driven downhill bike we made in my shed.
  • 32 0
 I'm on mobile so hopefully this link works for everyone: m.pinkbike.com/photo/24105034
  • 4 0
 @enduro29er: Buddy, I need more info! You ever take it off any sweet jumps? Is it using a geared hub for the gearbox? Do you still have the bike? Are there more pictures of the where the chains meet & the 'gearbox'?

So sick.
  • 2 0
 awesome!
  • 3 0
 @enduro29er: That's sick we need more info
  • 2 0
 MORE INFO!
  • 5 0
 @LeonV: I just dumped a whole bunch of build pictures into my mobile upload album if you want to see more. Not many good close ups of the drive system, unfortunately.

I only took a few test rides on it before I had to move away for grad school, but I remember the suspension felt incredible. To be fair, I was used to trail bikes with air shocks so not a great reference for comparison.

Good eye on the hub! Yes, we used a 3spd hub as a cheap gearbox substitute Smile

One of my project mates has the bike still last I knew. I did pretty much all the machining for the project and that was definitely my favorite part of the project. I can post a link to the project paper we wrote on our later when I get home from work.
  • 2 0
 Dude that's sick!
  • 1 0
 I made some drawings on fusion 360 of the same thing but with a trial freewheel and a threaded cog that is used to shift when coasting. I never built anything tho. So I don't know how he can patent that.
  • 1 0
 Cal Poly SLO, eh
  • 2 0
 @Scarredone: nope, SJSU. Thought about going to SLO for grad school but Berkeley made me an offer I couldn't refuse. I did some racing in the WCCC while I was at SJSU but this bike never made an appearance, unfortunately
  • 33 0
 2chainz…
  • 7 0
 Hey! he's "different"...
  • 5 0
 It will be in the next commencal edit
  • 4 0
 no idea how there is only 1reference to 2chainz in these comment.
  • 11 1
 Reminds me of the Cannondale Fulcrom DH bikes from 98 or so with the jackshaft (yes I know it's not the same, just reminds me of it),

www.theproscloset.com/blogs/mtn-bikes/myles-rockwells-1998-cannondale-fulcrum
  • 2 0
 Came here to post this. That bike almost kept me in engineering school just because it was so bonkers. At the time.
  • 2 0
 The only pro bike I had the chance of ride (around a parking lot) back in the end of 1998 when Oscar Saiz was invited to a race here in Portugal.
Mindblowing suspension action,zero stiction on both shock and fork. You could get the suspension moving with just pushing on the handlebar with your fingertips.
  • 13 1
 This really is pivotal news
  • 3 0
 Dave has really wrapped it around this one.
  • 13 2
 The innovation is that Dave Weagle is going to take their money if they try to sell that where his stupid patent is recognized.
  • 7 1
 The innovation of patenting it! The missing element of the brooklyn machine works is greed.
  • 3 0
 What year was that?

Lahar system predates this article by a good few years (maybe as much as 10 years when Aaron was turning up to races here in Aucklands Riverhead forest on his latest proto). www.pinkbike.com/news/now-that-was-a-bike-2004-lahar-m8.html

Also, Rob's Zerode G1 and G2 are basically the same, but transmission via an Alfine 'box.
  • 1 0
 It's different because the the tora has 0 anti squat as the second chinring is coaxial with the pivot. in DW's design the second chainlring is lower than the main pivot allowing to control anti squat and so pedaling efficiency. Same as for the starling shown in the article. Makes plenty of sense to me. what's new to me is that the claim is that we can finally get back to 2000's suspension performance to see bikes riding good again!!!
  • 9 0
 m.pinkbike.com/photo/19700617
I look forward to a pay out..
  • 5 0
 Better get in line behind Zerode (Rob Metz) and Lahar (Aaron Franklin). Kiwi's always doing stuff before you Aussies...pavlova is ours!! Smile
  • 2 0
 @handynzl:
I know them both and that's fine .
Also, you can keep pavlova haha
We can send a few movie stars back as well .
  • 3 0
 @latheboy: We only accept Crowes that play cricket...
  • 7 1
 Multiple chainrings around the crank? This is just Weagle's way of incrementally pushing us back to using front derailleurs.
  • 1 0
 if someone made a front casette and deraileur it would eliminate all the flaws of the current thing (hanging off the rear wheel and unsprung mass) without gearbox expense and drag. why not make an open bb and stick a casette in it?

edit: oops, the chain would be coming in loaded instead of unloaded, can't be done, wheel's in the way too
  • 2 0
 @baca262: look up Williams Racing Products on Instagram
  • 4 0
 Just sucks that this guy patents everything and small Builders will get sued if they try around with stuff or use it on their Bike that they prob just sell 5-10 of in their lifetime....Basically he's patenting something that is just a way of arranging components and not something he explicitly developed. But who am I to complain about this... lol
  • 1 0
 what do you mean 3500 bucks for a seatpost and i get a free frame …..really whata deal
  • 3 0
 Integrating this with the Supre Drive would have been a great way forward but I guess Weagle has long relationships with the big drivetrain manufacturers and he's supplying what is primarily an improvement for manufacturing in the status quo.
  • 4 0
 The Supre drive tensioner arm rotates to the top of the chainring so I don't see how you could combine them. Different drivetrains with different goals. I think the Supre has more potential though, and could also be used on e bikes.
  • 1 0
 @HelterSeltzer: I like the Supre, and the guy making it seems cool, but it still has the cassette in the wrong place, is exposed to the elements, and IIRC only works with one type of rear suspension.
  • 5 0
 Move the second chain to the other side, and file a patent. Slack, sue and retire early!
  • 11 7
 All of this bullshit complication and it still has a fucking derailleur. DW has joined the ranks of those that have lost the thread.
  • 7 3
 Please let us know once you have achieved (or have the resourcs) to devlop the holy grail internal gears MTB. I am sure DW is struggling and could use the asistance.
  • 2 4
 @bman33: It already has been done multiple times. Lahar/zerode internally geared hub mounted in the front triangle, pinion gearbox, Honda DH prototype, WRP, millyard, etc
  • 5 4
 @bman33: clearly he is struggling if he has to resort to patent trolling on other peoples ideas
  • 5 9
flag wburnes FL (Jan 26, 2023 at 13:25) (Below Threshold)
 @bman33: Dave Weagle, if you're reading this, f*ck you
  • 2 1
 @wburnes: and how many sales does Zerode have? I have ridden one. Nice, 'close', but still not as good as chain/derr. I am 100% on board with an internal gear bike once they are good enough to replace what we currently have.

And if I am correct, the Honda was just a cassette and derr hidden inside that housing, not a true gearbox as we think of it.
  • 1 4
 @bman33: you asked to let you know when they were developed. They already have been, multiple times.

They aren't close to being as good as a dérailleur, they are significantly better.

You're saying the Honda was gears-in-a-box, but not a gear-box?
  • 3 1
 @wburnes: Technically, and facetiously, the Honda was a gearbox as the cassette and derailleur was in a closed box (not sealed though). So by that gambit, if one was to cover a chainstay mounted derailleur and cassette in a box (not sealed though), then everyone can have a gearbox bike.

Gearbox drives like Pinion will get better over time. Now that electronic shifting is getting accepted, the gripshift bug-bear from some people can be removed. The Archer system is already halfway there.

But in response to "who did it first", then you have to include Lahar and Zerode in the conversation. I vaguely recall Aaron Franklin (Lahar) racing and riding here in Auckland on his high-pivot, dual chain, protobikes in the mid-1990's.

And after refinement... www.pinkbike.com/news/now-that-was-a-bike-2004-lahar-m8.html
  • 1 2
 @handynzl: I did mention Lahar and Zerode in my comment
  • 2 0
 @wburnes: here is a link showing what Honda did. Still pretty good execution...I would totally ride a modern version of this...

www.pinkbike.com/video/8166
  • 1 0
 @wburnes: Yes, I was affirming your statement *thumbs up*
  • 2 0
 Um, same as a Zerode G1 or G2...(apart from the gearbox), which is how DW will get around prior art.

zerodebikes.com/history-1

However, Lahar was doing this in the early 2000's (and even won some little races that the UCI called the World Championships)

www.pinkbike.com/news/now-that-was-a-bike-2004-lahar-m8.html
  • 4 0
 Here he is, still patenting hot water!
Kill potential competition and enslave them to royalties.
Will we also patent the H2O formula?
  • 2 0
 Ah, the things Bike industry's doing to avoid working on a refined and functional gearbox... This comment is coming from a guy who usually don't brag so much about gearboxes but the recent patents in the drivetrain department seems just nuts
  • 1 0
 that has been done many many times, and there are a ton of patents on similar and almost identical designs, but I have to admit, Mr Weagle is a master at patenting existings designs

ep1.pinkbike.org/p4pb1703188/p4pb1703188.jpg this is one I made a trillion years ago or look up purgatory bikes.
  • 6 0
 reminds me of BMW
  • 5 0
 Where do you adjust the tension on the small chain?
  • 1 0
 it may be that the chain is short enough for tension not to be an issue. If the run between the two cogs is ~10cm, even a 5% stretch in chain (you'd normally replace at 1%) would probably not be enough to cause it to come off.
  • 2 0
 @hughlunnon: that would require pretty impressive frame engineering and manufacturing to be able to make sure it is tight but not too tight to not need any sort of slack adjustment though.
  • 1 0
 Probably going to use an excentric bottom bracket. Otherwise a small chain tensioner, without a derailleur and the chain being very short and looping about 70% of the cogs it will have a very small tendency to come off, I‘ve seen people run single speed city bikes without any chain tension whatsoever, the chain sagging by several centimeters and still not coming off.

What bothers me about this design is my ankle passing the teeth of a cog place outside and above the main chainring with each revolution of the crank…
  • 4 0
 This is so totally not state of the art. He should have never been granted a patent for this design.
  • 1 0
 chain do not transmit any torque power to regular idler pulley, so no pressure on idler's teeth .... unless you drive another idler with a second chain...then you have power loss and worth looking at a better bigger idler.

I would be curious to see the chain tensions comparison before the idler and after and see the reel power loss then compare results with Dave's design.

I do believe this will go to market but not for these reasons stated above but for an add-on motor driving actual idler to convert regular bike to ebike. If it's not the case and you find that idea cool, good luck patenting it because...the idea is now public on this post Smile
  • 5 0
 THEY CALL EM 2 CHAINZ CUZ HE GOT 2 CHAINZ
  • 1 0
 .
.
Will it see production?

When I talked to him, Dave wasn't over-selling this idea. "Do I think that 150 mm bikes will be running around with this technology? They could... but I'm not going to sit here and tell you it's going to be some superior riding thing," he said." "It does work and it solves a bunch of issues. It has its small range of places where I think it's applicable and useful... We'll see if it goes to market - I hope it does."
.
.
Solves a bunch of issues and creates a bunch more.
The issue with my bike is the rider!!!!
I cant manual it so its the bikes design that is at fault right....
.
More elephants gonads in the patent world to block technology or get money from people wanting to use the technology.
  • 1 0
 It seems to me the optimum system starts with a crank sprocket like this one, but leading to a 9-speed boxed derailleur over the BB like on the Honda RN01, with the output sprocket right on the high pivot position, leading the chain to a normal hub for DH or a 2-speed internal gearing rear hub courtesy of FFWD for trail/enduro.
  • 5 0
 RIP pant cuffs
  • 4 0
 Normal mountain bikers wear capris anyways, at least that's what Pinkbike tells me.
  • 4 0
 Didn't Brooklyn Machine Works do this about 30 years ago?
  • 1 1
 I think the difference is this patent keeps all the chains on one side of the bike.....
(If I've read the article correctly) meaning it can use a regular crank......?
Seems a bit pointless to me when bmx has had LSD cranks for over 20 years.
Cool story B, my mate made the first ever LSD hub when I worked in his skate shop in like.... 2005
  • 1 0
 @naptime: This is not the first. Lahar had it in the early 2000's (and if my memory serves, Aaron had this setup on his very early bikes he used to race on in Riverhead in the 1990's)
  • 1 0
 @naptime: ah yes the classic "cool story bro" and then a cool story lol
  • 2 0
 OK... I've been staring at Fig 7.F and Fig 7.G for five minutes now... and I believe they are identical. Am I missing something? Is this a test?
  • 1 0
 Looks like the math is driven by 'average teeth'. Not British?
  • 3 0
 I'm going to design a rear suspension that uses 3 chains. Just to get a patent to hang on my wall.
  • 1 1
 Dave Weagle is basically just really good at patents and has done an incredible job locking down IP and cashing in accordingly. He has also done exceptional at repackaging his designs and selling them to companies like Canfield to give them their own marketing edge.

This is yet another one of those "already exist but play the wording" patents. What a corporate game to be played!
  • 3 0
 Pretty sure one of the actual Canfield Brothers designed CBF & holds the patent
  • 1 0
 A small error in the article. Pedals already self loosen with the chain ring on the right side. I’ve always wondered why the thread direction is this way? Other than right on right and left and left.
  • 3 1
 Oh this is great! I can not wait till someone fits a third chain in there! super clean and fun;]
  • 1 0
 So good, but why stop at 3? Room for a few more surely
  • 3 0
 One great step towards being a gearbox....or is it!?!?
  • 4 0
 Here we go again.
  • 3 1
 Great - time to make a bike that sucks going uphill (high pivot) and sucks going downhill (DW Link)
  • 4 3
 If Specialized buys this design, then it'll suck. Until then, it's awesome.

FSR "sucked" until the patent expired, now every company that uses it claims it's awesome.
  • 2 0
 To be fair, some companies literally switched to a chainstay pivot layout for marketing reasons...as in their engineers would say the kinematic changes were so minor that a precious few riders would actually be to tell the difference in terms of performance between the non-FSR model. To that end, I still ride 2 bikes that are the same model but the older one is a "faux bar" design and the newer one is a FSR model, and the difference is ¯\_(ツ)_/¯

Not that a FSR is bad or anything, its just much less of a difference/advantage than some make it out to be.
  • 4 1
 Have you seen my 2x crankset?
  • 1 1
 Dummy. It is 1x...
  • 1 0
 Yep, and they jam, make noise as chain bounces around, take up critical pivot/linkage space, etc etc.
  • 2 1
 LSD cranks have been in the bmx world for like 20 years! F sakes, it took MTB long enough to get on the direct mount chainrings
  • 2 3
 Totally the wrong direction for bike development. Some company needs to take the Tesla approach of relentless simplification, improvements and cost reduction. I don't think adding these components needed for a high pivot design and their benefits are worth it. For an e-bike, sure as it is already more complicated, plus a gearbox drive integrated into the motor makes sense and will probably be coming soon. That would make the high pivot design even easier.
  • 1 0
 Yeah they should make an ebike that already has wireless brakes but you can't use them unless you pay for the over the air update
  • 3 0
 So he put in for a patent on something we did 20 years ago? Oki doki.....
  • 2 0
 Oui un Balfa Nouveau riche!!
  • 1 0
 27 years ago
  • 2 0
 Well damn, I shoulda patented this.

m.pinkbike.com/photo/20220761
  • 2 0
 Now Dave can sue even more bike companies because that’s all he seems to do lately.
  • 1 0
 His patents are highly entertaining to read. He will claim this works on horse drawn wagons, steamships, carrier based jet launchers and nuclear power plants.
  • 2 4
 I'm blown away that you guys don't know how pedals thread into crank arms...when you install pedals, they thread in while you're pedaling BACKWARDS...when you take them off, you pedal FORWARDS. Anyone that has had a pedal like a Straitline, where the end of the spindle can drag on your shoe sole, they had a tendency to unthread form the crank arm...drag on the pedal bearings actually will UNTHREAD the pedal from the crank arms.

The reason they are threaded the direction they are is from the early history of bicycles which had primitive bearings in the pedals and the 'standardization' of that interface, and also why they are Imperial/S.A.E. thread, 9/16 for 3 piece or 1/2 or one piece cranks, not metric.

Same with your BSA/English threaded Bottom Bracket, drag on the bearings actually LOOSENS your BB while you're pedaling. Don't believe me, put your bike in the stand, loosen your pedals while spinning the cranks, it only unthreads while pedaling FORWARDS!

The reason for this was the primitive bearing design from the early days of bicycle development would tighten everything, and make it harder to pedal, and destroy the bearings, so they create adopted these 'standards' that we still use today. After long rides back then, everything would loosen up, and you would need to take it to a mechanic for a 'tune up'...

Now that we have much better designs with circlips, lockouts, etc...we don't need 'tune ups' as often as we used to...

STUDY HISTORY!
  • 1 0
 Ya know, I bet 99% of people on here thought it is for retention purposes (including me) so I don't think we're idiots so much as you are smart.
  • 5 0
 I've heard two other explanations for the thread direction:
1 (also history based, I heard it through Sheldon Brown's website): with fixed gears, if your pedal bearings lock up while at speed, you loosen the pedals instead of break your bones.
2 Precession (in this meaning of the word:https://en.wikipedia.org/wiki/Precession_(mechanical)), not bearing drag tightens or loosens pedals, and loosening them while riding was the problem that reverse thread fixed.

These two explanations can both be true at the same time, but the precession and drag arguments contradict. I do know that even my very crappy draggy bearings of my commuter bike pedals don't loosen my threads, so I am more siding with the precession explanation.
  • 1 0
 @ak-77: Ah, the precession makes a lot of sense, and explains why everyone thinks it is for retention.
I feel like bearings would just spin on most pedal spindles if they lock up. Also, I think a situation where a pedal bearing suddenly locks up is very unlikely. Worst case it would probably blow out, though maybe a needle bearing could jam.
  • 1 0
 Anyone that has had a pedal like a Straitline, where the end of the spindle can drag on your shoe sole, they had a tendency to unthread form the crank arm...drag on the pedal bearings actually will UNTHREAD the pedal from the crank arms.


Huh? I’ve got 13 year old straitlines on my DH bike and not even once have the come loose. My trail bike has 8 year old straitline’s and never have the come loose.

I’ve rebuilt them 3x and I bought 2 more rebuild kits when the announced they were discontinuing the brand.
  • 1 0
 @itslightoutandawaywego: Since it never happened to you it has definitely never happened to anyone.

I'm sure it could happen under specific conditions. According to that wiki that was linked precession can create orders of magnitude more force than drag so it is not surprising you haven't had one loosen.
  • 1 0
 Reminds me of the Balfa Nouveau Riche, made it 1997... and sold from 1998 to 2001
  • 4 5
 Trek stole DWs Split Pivot behind closed doors and rebranded it ABP. Giant stole DW link behind closed doors and turned it into Maestro. Wonder who is gonna try to steal this one.....
  • 3 2
 Yep, Trek's move specifically was super shady for sure
  • 7 1
 Based on his history of patenting the obvious, I would question his side of the story as well as his claims to the design. Those companies have just as much right to do something like that as he does patenting things that already exist.
  • 6 0
 Giants pivot link is ahead of the bottom bracket, and Niners link arm not only has a pivot ahead of the bottom bracket, but the link runs under it. The systems are not the same. They are similar.
  • 1 0
 If it was such an obvious steal why didn't he take it to court? Patents don't mean a thing until they are tested in court, especially in the US patent system. EU is more strict in what they allow but there too patents' validities are only truly tested when taken to court.
  • 1 1
 Trek also charges over $100 for an aluminum dirt jumper frame
  • 2 0
 @freestyIAM: Ah, I see. And he lost the case. Because what he patented wasn't just a pivot location but also some other details like leverage curves. Probably because the pivot location alone had been done before or was too general? Anyway he lost the case, lost the appeal and had to pay Trek 40 k in legal costs. www.bicycleretailer.com/north-america/2016/01/04/court-pares-split-pivots-legal-costs-failed-suit-against-trek .
My guess is that what this drivetrain patent covers is also a pretty narrow range of implementations, and the patent will be used more as a marketing tool than actually preventing others from selling something very similar.
  • 1 0
 I dont think I will ever be a fan of these, just adds more parts and creats more drag. Got to keep the market fresh though.
  • 2 0
 What's up with that delicate dangly thingy in the back?
  • 1 0
 Even before Brooklyn, there was the Cannondale Fulcrum. Dave can currently Trust that he's about to get sued for once.
  • 2 0
 Brooklyn Machine Works is back in the game it seems.
  • 1 0
 If Dave Weagle gives birth to anything remotely new, Evil's employees might actually have to go to work again.
  • 1 0
 Let's be honest it's not a serious MTB patent unless the drawing of the bike looks like a department store BSO
  • 2 0
 It looks like an Effigear system reworked to drop the gearbox…
  • 1 0
 I wish he had also ditched the need for a derailleur while he was at it Smile .
  • 2 0
 great job must have been hard to copy brooklyn machine works lol
  • 2 0
 Why patent this? Does he forsee someone actually using this? Why.
  • 1 0
 Locknuts, not lockouts...stupid autocorrect...
  • 1 0
 now im hoping for a high pivot ibis DH bike!
  • 1 0
 Do not hold your breath. -Scot Nichols
  • 5 4
 Slap a battery on this, and attach and AI virtual assistant and I am in!
  • 1 0
 I wouldn't wanna service the little chain
  • 1 0
 What is this "service" of the chain you speak of¿
  • 1 0
 @naptime: clean TF out of it when I mud it up, I hate hearing the crunch of the chain against the chainring. So I run it through a chain cleaner and then obv lube it
  • 1 0
 yet you probably do service your little chain, a lot.......
  • 2 1
 Idler is still my choice...for an ebike it makes sense
  • 3 2
 nice of him to put it out there for Trek and Giant to steal
  • 1 0
 One hopes you're being flippant... otherwise you don't understand patents...
  • 1 0
 @handynzl: you maybe don't understand that they can still be challenged and litigated in USA. which takes money. Patent judges are not infallible. see: ABP.
  • 3 2
 Color it blue and call it my own. Douche Weasel at it again….
  • 1 0
 All he needs is Sam Hill to race it on Sunday and history will be reset.
  • 1 0
 DW is a mtb lord. Don’t diss it!
  • 1 0
 “Shhhh! Do you want to get sued?” - Groundskeeper Willie
  • 2 0
 New Pivot Doughnut
  • 1 0
 Seems that 7x2 will be back to unsprung rear weight
  • 1 1
 "...like the Starling pictured below on the left."

Guys we're on our phones. Please stop writing and designing for desktop.
  • 1 0
 More weagle room for bike designers! Sick!
  • 1 0
 2Chainz has entered the chat
  • 1 0
 Tora Cycles now what ?







Copyright © 2000 - 2024. Pinkbike.com. All rights reserved.
dv56 0.057825
Mobile Version of Website