Inside a MotoGP Seamless Gearbox Replica - How it Works

When you can't get access to the real one, here's the next best thing! This has been an incredible amount of work to get to this point and it's still very much a work in progress, but I wanted to put this video out there to bring this incredible piece of technology to light.
There is still work to be done, but for now, enjoy!

[@electrosau2]

I do not know what is more genius. Inventing this gearbox or being able to reverse engineer this from only patent drawings. Keep up the good work 👍

[@rexleen3585]

A multi-color 6 in 1 ball pen

[@SupernovaSpence]

Dude, for how many viewers you have, I’m surprised at the quality of your work. Keep it up. You earned my subscriptions tonight

[@TimmaethBoy]

I love being able to showcase what I find fascinating to others. Thanks for the kind words.

[@boredKiwi]

Thanks for explaining this design, something I was not aware of regarding this racing series. This seems to be a more sophisticated variation of the ball-selector gearboxes that were common many decades ago. My early '70s DKW 125cc (6-speed) and '55 Ducati Cucciolo moped (2-speed) both had this type.

[@1crazypj]

It seems to be a re-engineered over complicated version of the ball lock I first saw on a Yamaha 80 around 1968. I guess using free wheel pawls allows them to overcome patent infringement issues? That was a nightmare to set up as a per-teenager without a service manual, at least this looks a little simpler even if it does have a lot more parts to go wrong, no wonder they barely last one race.

[@filippostube6533]

1964 hodaka

[@boredKiwi]

@@filippostube6533 that's right! That fact was parked far in the back of my brain and needed a push.

[@jeanquadvandamage9211]

Thank you for being curious enough about this technology to take the time to make a working model. The design is really clever and complex. I can only imagine how much time and effort you had to expend to get this far. You're the only person I've found who not only went through the process, but shared your results and explanation with the rest of the world. Fascinating stuff.

[@TimmaethBoy]

Glad you enjoyed the video.

[@fibonaccisrazor]

Excellent video, great to see 2D patent drawings translated into a working 3D model! Fascinating mechanism, awesomely communicated.

[@TimmaethBoy]

Appreciate the kind words. Glad you enjoyed it.

[@zeprahzzz]

I'm amazed some people can just spend some time studying a patent and basically become a subject matter experts and be able to give a 50 minute lecture on it.

[@TimmaethBoy]

Just fascinated with mechanisms in general enough to go down a rabbit hole and share my enthusiasm with others.

[@cptwingnut576]

Excellent video. Really appreciate all the effort you have put in trying to explain a gearbox that the manufacturers would rather keep a secret.

[@TimmaethBoy]

Thanks! Glad you enjoyed it.

[@angelosilva342]

I just gained 10iq points from watching this. Thank you so much. Excellent presentation!

[@Neosho1337]

This is an incredible video, with a very clean and clear explanation on how the gearbox works and maintains seamless engagement. Such a clever set of engineering decisions from Honda, and you did a great job of adapting the designs to a 3d printed design while maintaining functionality.

[@TimmaethBoy]

Thanks! Glad you enjoyed it.

[@davidemantovi6678]

I remember back when this patent came out, trying to figure out how it was working, but as you said nobody really had any type of info, so everyone was just guessing. And now after 11 years you just explained perfectly 😊 I just don't know how to thank you Tommy. Amazing job!!! BRAVO 👏

[@Orionleo]

I found you to be good at describing what has always been to me something hard to understand -- clutches and gearboxes. (They seem so arcane and rudimentary for what one would consider 'modern technology' and is enlightening because modern technology is sometimes built on very very foundational tech, like gears and ratios." The camera not focusing was sometimes a little frustrating but thats not really your fault. I think you did a great job in describing something that is probably extremely complex.

[@ottonormalverbrauch3794]

Looks like a sophisticated Zündapp 50 cc gearbox; all gears interlocked and one being locked into gear with a set of bearing balls pushed in place with a push-pull rod with a notch inside the axle. The balls acting as a lock for up and downshift.

[@filippostube6533]

1964 hodaka

[@BeamRider100]

I can tell they've got parts of the idea from other inventions too. Looks similar to a bicycle hub freewheel, but that only works in one direction and there's no shift. Thanks for showing the details as I was curious about this. It's definitely a lot more complex than the zero shift system which reduces components but is very similar to the usual synchronous gearbox.

[@sparty94]

very interesting, you did a great job of explaining this gearbox. your 3D printed model really helped me understand it.

[@TimmaethBoy]

Thanks! Glad you enjoyed it.

[@vikramhao]

Very well done Sir! I am looking forward to seeing the final product

[@mk1cortinatony395]

Amazing video! I have worked with many transmission but never seen seamless stuff like this. Very clever engineering and VERY clever reverse engineering by you. 👍

[@RelentlessRage]

Really clever design, i imagine how smooth shifts would be with electronic throttle control (automatic rev matching). Thank you for covering it, all tho it was kinda time intensive, but still

[@TimmaethBoy]

Glad you enjoyed it.

[@noral342]

Isn't that auto blip which is in many commercial bikes?

[@TimmaethBoy]

​@@noral342 Auto blipping, yes. This gearbox design, no.

[@alesksander]

i think throttle control would defeat purpose of this system. Most clever thing about this design is that its gets naturally aligned.

[@RelentlessRage]

@@alesksander It will not defeat the purpose, just make it even better, because ECU now have to correct rpm much less

[@chesthairascot3743]

I worked on the quick shift systems from Muzzy's years ago. They cut the injectors to avoid backfiring. Other systems cut ignition though.

[@tintruder224]

Hodaka did something very similar back in the 1970s. Instead of pins driving levers, they used balls, which directly engaged detents on the inside diameter of the gears.

[@schwerti94]

German motorcycles already had this in the 50s. In German it is called "Ziehkeilgetriebe". It was used on a large scale, especially in small 50cc motorcycles of the brands Zündapp, Simson and Hercules from the 60s to the 80s.

[@joshlewis5065]

Wow, that's really clever. Works exactly like a standard 6 pin cylinder lock. I love seeing old technology used in wildly different applications. Though this application is new, the mechanism is 230 years old

[@formbi]

a click out of one, two is binding…

[@billynomates920]

@@formbi click! we have selected the green ink barrel...

[@thecolgatemann]

great video, its sick to know how this top level technology works. Looking forward to next video! :)

[@malcolmbennett9381]

This gearbox looks very similar to the Lotus "queerbox" designed by Colin Chapman for his F1 cars in the early 1960's. It wasn't entirely successful, even though Keith Duckworth (of later Cosworth fame) was given the job of making it reliable without redesigning it. The shift mechanism was internal and sequential but not seamless as in this MotoGP gearbox.

[@TheQuantumPotato]

Incredibly impressive work putting this into a 3d model! There's an enormous gap between conceptually understanding something technical and actually being able to put it together, and people who only conceptually understand it and decide to stop there don't always realise how much they don't know.

[@TimmaethBoy]

Appreciate it.

[@uackoz]

You’re great at explaining stuff, thanks for putting all that effort

[@TimmaethBoy]

You're very welcome.

[@michaelpayne6441]

Wow! Fantastic job. As a professional gearbox designer I can honestly say you could do very well in this industry (if you aren't already!). Maybe like others have suggested, it might be worth contacting the manufacturers and gearbox specialist if working in this field is of interest to you.

[@TimmaethBoy]

Thanks! Glad you enjoyed it. We'll see what the future holds.

[@NotEvents]

Great Video ! I was "engaged" (ha-ha) for the whole time ! The pace you presented it at... I was actually able to understand your explanation of how it works on the first time through ! 😀

[@TimmaethBoy]

Oh you punny. :) Glad you enjoyed it!

[@603mike]

Would be cool to post the STL files after you’re done just so some of us could have a model of our own. Awesome work!

[@adamdunn7257]

Definitely would love to see some more follow ups to this. Subscribed.

[@johnnym1320]

Pretty cool that you built this just from patent drawings, I dont know if you are aware of this but in the motorcycle drag racing world we have been using what we can an over ride transmission for over 40 years, shifts with no power cut, but only for up shifts as we don't need down shifts in drag racing

[@brookwillard]

What a great video, thanks for making it!

[@TimmaethBoy]

Thanks!

[@froat1]

My brother had a 1962 or 3 Tohatsu 50 street bike that that had a similar system except it used a ball-bearing sphere instead of the dogs(?) that are used here.

[@jh-tech5546]

Great video! Perfect explanation. You did a great job. Thank you. Seamless gearbox mystery unraveled for me.

[@akagodofheaven]

This video deserves more love ! Great job ! Enjoyed every single minute and learned a lot Thank you very much !

[@TimmaethBoy]

Glad you enjoyed it!

[@dhushyanth-qh9qy]

It's really amazing and perfect explanation dude congrats

[@markzuro3592]

Amazing work thanks

[@Africatwin93]

Fantastic effort to explain something really special. Thanks a million

[@TimmaethBoy]

Thanks!

[@toxicnerveYT]

Absolutely brilliant video, thank you for taking the time to produce this. Also shout out for the Gamer's Nexus desk mat! A man of taste, I see.

[@TimmaethBoy]

You're very welcome. Nice catch on the mat. :)

[@dougbawden4321]

Excellent video. That's some serious brains to design something like that..

[@SuperGemma2010]

amazing demonstration, your a genius mate, its a complex version of a boat winch that uses pawls and springs, the pawls are the drive engagement levers, you couldn't have demonstrated this any better, I hope you are a teacher, love your work mate

[@TimmaethBoy]

Actually am one. :) Thanks for the comment.

[@JohnBrown-vn2qw]

you are the man! big thanks

[@hectorfoss6180]

awesome man !

[@KTMSAS-Duc1200S]

I can not imagine how much time you have spent on this but I have wanted to see how these work for some time. Thank you for all the time and effort you put into this. I thoroughly enjoyed it!!

[@TimmaethBoy]

A lot more than I'm willing to admit. :) Thanks!

[@psychogiux2633]

Congratulations for your hard work and thank you for the explanation 🙏💪🏽😀

[@TimmaethBoy]

Thanks! Glad you enjoyed it.

[@goransolheim8772]

Dual clutch action with a single clutch very cool video

[@luddite6239]

Fascinating! A brilliant design, brilliant explanation and a brilliant 3d recreation! Thank you. I've been trying to understand how this works since they were first revealed, especially how the gears deal with the back torque of engine braking. The actual bearing surfaces seem quite narrow, considering the amount of power being transmitted. Now, if you could see inside the, (presumed), mass damper device in the Ducati tailpiece and explain that...! Subscribed on the basis of this - thanks.

[@TimmaethBoy]

Glad you enjoyed it.

[@jeremysarver5094]

Great video

[@keithbrown1363]

1962 Capriolo did the same thing with balls being lifted into the gears by a flange on the shift shaft. Way simpler than the Honda system

[@romualdaskuzborskis]

Problems with balls is- they do it rigidly. The "ramp" allows ring to slip in place by itself for a split second.

[@springford9511]

The reason for the duplicate pawls is so that there can be a ratchet. This allows two gears to be engaged at once without an explosion. There is literally NO interruption in the torque from the engine to the wheel. I made a relatively long post about it a minute ago. I hope it might not be complete rubbish 🙂

[@cosinus_square]

So a keyed shaft and a a bicycle freehub ratchet for inspiration? Damn clever, that's what it is.

[@alro2434]

Thanks, nice work! The sliding internal engagement has had a lotta variations for a lotta years, just less robust then this. My examples are 50's Zundapp & Vespa.

[@TimmaethBoy]

Interesting. Didn't know that was a thing on older model gearboxes.

[@jamest.5001]

12:46, it's like a one way bearing engagement, dis- engagement, per gear. I'm surprised this wasn't designed in the 40's or 50's. I have had a idea about using planetary gears in a manual gear box. It was all in my head, and been years, so a lot was lost. I can't recall exactly how I was thinking shifting would happen. But it wasn't traditional hydraulic. However it would be mechanical. Something similar to this . It would make a transmission say, in a car tiny compared to traditional. Something like a model T Ford transmission, only more modern and performance oriented. I was thinking about 8 ratios possibly more. With the ability to use a TCM/ECM together to change the gate pattern. To skip shift without noticing while shifting. Also other fear ratios would be possible, dependant on how the planetary was used, being two ratios possible per planetary. So a 6 or 8 speed could in theory be 12, or 16 speed and possibly more if multiple planetaries are engaged at once. Possibly a ultra low ratio using all, , and a inverted drive for overdrive ratios. It could use 4 planetaries for possibly 12+ gears basically use all for first (except the overdrive) the 3,2,1 and then use overdrive with each gear, splitting the ratio adding a gear. So that's 8 gears plus overdrive. Then the two ratios per planetary. 18 gears, then there is splitting gears , using all planetary gears in alternative ratio. Leaving who knows how many possible gear ratios! It in through could nearly operate as a cvt, with stepped gear ratios close enough the rpm can basically stay steady during acceleration. Using 38 ratios to allow smooth acceleration. It would require a computer to work out the ratio requirement for the given speed and tq requirement vs engine rpm. To select a shift gate with only the appropriate gears available . Also a similar gear box could be used with electric motors to make them more effective in vehicles. Using a couple planetaries .with overdrive making a small motor more capable. Allow a small very high rpm motor to move large vehicle, and still operate at highway speeds. The use of hydraulic power to shift isn't a bad idea. With electric motors a tq converter isn't required . I always wanted a manual clutch with a automatic transmission. Use the clutch for taking off, then shift gears hydraulically . The dampers in the clutch would get a workout. It should be more efficient. Fun to drive. Nothing beats at least 4 Speed manual transmissions tho. ,8speed would be cool. 5-6speed+2-3 overdrives. Or possibly a under drive sub 1st gear, not quite a 'granny gear, for hills and such making it easy on the clutch. Sorry to ramble, have a awesome day!! 🎉

[@stevegreen2432]

Very well made and even better presentation and explanation. Very educational. Learnt a lot from this vieo. Thanks for sharing.

[@TimmaethBoy]

Thanks. Glad you liked it.

[@mofalaufkultur46]

Great great job!! 🎉❤

[@TimmaethBoy]

Thanks!

[@daavegriffo99]

Splendifferous!

[@vitalic_drms]

this is great

[@xaytana]

I'm curious if Honda, or any other team, ever experimented doing this with a centripetal clutch, instead of using cammed dogs. If they're already rebuilding these every race, why not explore other methods. So much complexity with the timing mechanism could be taken out by just changing to clutches, not to mention you could hypothetically push much more power through the clutch mechanism than you can with two pivoted dogs; essentially moving potential failure points from those diving pivots to at what point the clutches slip or what the teeth of the gear can handle. The same kind of selector would probably be used, a cam mech with previous gear retention, though given the radial nature of centripetal clutches it'd probably be simple to use a radial action on the selector. This would also be cool to adapt to a hydraulic system to replace the cam selector just a series of valves and pressure differences determining which clutch pack engages, imagine throwing this into a kart and just having shifter paddles; though this quickly becomes just one step away from just an automatic transmission. I almost want to see this scaled up for use as a sequential in a car. Surely reliability would go up with scale, beefier components and more room within the package to provide robustness.

[@Iowa599]

Cutting injection is likely, for shifting on a GP bike. dumping fuel with no ignition has the potential of backfires & washing the bores.

[@zr6ajl]

The engine response to a fuel cut is far too slow to achieve the desired result, and the risk of engine damage is extremely high. It is far safer to use ignition cut even with the negligible risk of bore wash. Ignition cut used to be common, but modern ecu's now use ign retard. The engine only needs to lose a little power for a few milli seconds, it doesn't need to lose all the power. This gearbox design negates the need for any cut or retard. Power delivery is never lost even for a few milli seconds, so the bike will naturally be faster around a circuit only because of gear shifts.

[@233kosta]

The first iteration cut spark, yes. Those can go on any bike. They make that loud pop for that reason. Newer fuel-injected bikes (especially ones with factory quick shifters) will cut fuel. Because you don't want to be dumping raw unburnt fuel out of your exhaust if you can help it. That's less fun (no pop), but it works just as well.

[@jakes9649]

This was awesome, thank you for taking the time! Incredible printing and engineering skills on your part! Honda, having patented this means that there must be 3 more ways to build a seamless gearbox? (ie, Assuming Yamaha, Suzuki and Ducati all built their own versions?). Can you do a comparison? These boxes are so interesting..

[@GamezGuru1]

not if they pay royalties to Honda...

[@beachboardfan9544]

Feel free to make this vid hours long! This is the first time I've ever seen a physical representation of one 👍

[@joshb3929]

Amazing walkthrough of what all together is a very complex system but broken down into very simple stages. When you compare this to something like a DSG, it’s brilliant in its simplicity. Any ideas on what parts seem like the bits that wear out quickly? Been rumours that Ducati have been developing a version for their top end road bikes for a while, to sell to customers. Can’t imagine we’ll see them until the longevity at least gets close to matching the service intervals of existing gearboxes.

[@TimmaethBoy]

If I had to guess, the parts that would give Honda trouble are the cam rods and levers, but that's purely speculation on my part. I did check out the Ducati patent a while ago to see what they were doing; it's completely different from what Honda are doing at the moment. It'll be pretty cool to see it in public one day though.

[@GamezGuru1]

a DSG is infinitely simpler than this! Maybe from the outside, this gearbox looks 'simple', but only because the shifting mechanism is within the main shaft. This would be incredibly complex to machine, assemble and have work reliably, plus maintain it.

[@landlocked4771]

You do this so well, I subscribed as well. Well done. What type of printers do you use. That center tube with grooves inside must have been difficult. I see you also watch Gamers Nexus, deskpad gave it away. Thanks again for you work and video time.

[@TimmaethBoy]

Thanks. I use an older Prusa i3 MK2.5s, but still works very well.

[@satibel]

also the spring for the ring (at 32 min) probably cushions the not-dogs slightly when they slam into the lever.

[@halohat2286]

Has any MotoGP contacted you to become a team member? You're a badazz 💯

[@TimmaethBoy]

Haha afraid not. That would be cool though.

[@justRD1]

many times motorsports gearsets end up being 25* pressure angle instead of a standard 20* PA. Cool video!

[@TimmaethBoy]

Thanks!

[@paradiselost9946]

shorter stumpier teeth with less interference, and the extra bearing loads are less of an issue than getting maxi strength/min weight from components...

[@Lynxtro]

If I’ve understood correctly when you shift to 2nd the 1st gear lever arm is no longer wedged against the gear. As the arm is spring loaded there is a force holding the arm up but the force from the cam (which is also spring loaded) can overcome this and push it down? Great video.

[@TimmaethBoy]

So when you shift into 2nd, 1st gear is still technically engaged (briefly) because torque is still being applied to 1st gear via the lever mechanisms. When the levers for 2nd start transferring torque to 2nd gear, that naturally takes pressure off the levers for 1st gear since 2nd gear spins faster than first (lower gear ratio number); this causes the levers to release from 1st and 1st becomes disengaged. The result is an uninterrupted shift / no loss of power. The only reason this is all possible and things don't just go boom is because of the interaction between the control rod, sleeve springs, cam rods, and levers. It is all balanced and coordinated to work seamlessly, well, at least when things go well that's what it's supposed to do. Hope that makes sense.

[@NoName-fc9dp]

This is a very well done video, amazing explanation. I would love to print this for myself, are you planning on uploading the files anywhere? It’s very well made

[@TimmaethBoy]

Thanks! For the time being, probably not. It's still in the prototyping phase and still a lot of fine tuning / additional modeling to do.

[@dubsydubs5234]

Just bounce the clutch and stay full throttle while you shift. Only suitable if there's a rev limiter.

[@_droid]

Cool design. Do you have ASD?

[@jimmimak]

Thanks for sharing, it was interesting to learn how it works and it is an achievement to make this just from patent diagrams. I think the camera is trying to focus on your fancy desk mat instead of your amazing 3D printed model :) a plain background might help perhaps? I've got to be honest, I had to watch at 2x speed, as a design engineer I have seen free wheel pawls, cam rods, springs, levers, gears etc. before and I just wanted to know how it worked and what made this seamless vs a normal gearbox. I'm still not sure it's seamless really, but at least it minimises the seams.

[@springford9511]

No idea if this will help and maybe you get this anyway. I think it is like this - On an upshift under acceleration it disengages the overrun pawls in the current gear then engages the drive pawls in the next. This allows the "old gear" drive pawls to ratchet backwards even as both gears are "engaged" together. So there is never any neutral period. There is drive in the lower gear then suddenly there is drive in the higher gear as the higher gear drive pawls pick up the load. Seems pretty seamless to me. The engine torque is always transmitted to the rear wheel, without ANY interruption. After that the remaining pawls are sorted out. They are not loaded so that is no problem. I am not sure if say upshifts are allowed on the overrun. Of course the engine RPM will have to adjust instantly, but these bikes have no flywheel and the ratios are pretty close so the seaminess from that might be quite small. On upshifts the engine will have to be slowed down by transmitting more torque to the rear wheel so a small jerk forwards. I haven't really got it all sorted out regarding downshifts 🙂🙂🙂 Or upshifts on the overrun, but that is hardly a racing maneuver. My guess is that Honda will have sorted all 4 cases out, but I am not sure. They will all be, disengage the unloaded pawls on the current gear, engage the new to be loaded pawls on the new loaded gear, then sort out the rest. Hope this is not gibberish:-)

[@mr.2minutes161]

i still dont get the control rod slot thingy, how is it decide when to slide or locked from the control rod? what's stopping it from sliding further when getting to higher gear? how's it not slide out of the assembly on downshift?

[@Hix066]

Does anyone know what the Patent number is? Or even better, have a link to the pdf? Great video by the way, really well presented.

[@danilodestefanis9711]

what if i downshift while accelerating? or upshift while decellerating?

[@233kosta]

Looks to be a very violent process, no wonder they need to be rebuilt so frequently. Makes sense why they're not used on road bikes.

[@brandonlewis2599]

You should make a single-speed version with clear side covers, so it's easier to see the action of the cams and levers.

[@springford9511]

Well maybe a two speed version :-)

[@jaumecomas3290]

Great video , where we can find the files of Honda?

[@TimmaethBoy]

patents.google.com/patent/US8616078B2/en?oq=8%2c616%2c078

[@Iowa599]

Why not use some metal or a composite (glass or carbon) to replicate bendy stuff, like the shift rods?

[@qoph1988]

Wonder when I can get one...

[@jpmorgen5726]

I have always been amazed that those small parts can withstand 250 horsepower. I wonder if Honda got the idea in the beginning by seeing the old Sachs engines transmissions?

[@RENIELTUBE]

They prob. where inspired by the lockpicking lawyer 🙂 The entire principle is analogue to picking locks. Always keep torque on the lock cylinder while searching for the indexing pins currently bound up.

[@cynic5581]

Those cam rods remind me of one of those old Bic multi color pens. Bic invented the seamless gearbox, what you up to Honda?

[@navsimransingh]

Great video! I'm really interested in 3D printing and was wondering if you could share the STL files for this awesome design.

[@TimmaethBoy]

Unfortunately, this is probably something I won't be sharing due to its complexity and how much time it takes sanding / filing everything to make it work. This isn't the final product either and is still very much a work in progress.

[@TheRalliowiec]

What 3D printer did you use? Quite the quality print of the gears as I don't see any striations on the face of the teeth. Also, what you described seems like its a lot simpler than a dogged transmission considering there isn't a complicated shift drum or shift forks/shafts. Also, wouldn't this design make for a good automatic transmission in a car? All it seems to need is a torque converter (as a clutch) and a stepper motor under computer control to pull/push the shift pin. Is the reliability the only thing holding it back from such an application?

[@TimmaethBoy]

There is still a shift drum that is required to move the internal shift rod mechanism; I just haven't gotten around to making a prototype that interacts with the model in the video. This is by far way more complex and intricate compared to a standard dog box transmission. I am not so sure this would work well in an automotive application considering how much more power / torque a car can produce compared to a MotoGP bike, so I'd imagine these components would not hold up well to that abuse.

[@TimmaethBoy]

Oh and I use a Prusa i3 Mk2.5S; it's a bit dated compared to what's offered now, but it's still a beast.

[@Mike40M]

One thing I don't understand is design of the layshaft. Basically a gear gives a force for driving and a force bending the shaft. Due to the pressure angle of the gear. A conventional gearbox with dogs will have longer shafts than this design. This design has shorter shafts. Still needs a sturdy shaft. The pawls you call levers, was used in kick start mechanisms back in the fifties.

[@markrix]

Where can we download the 3d files?

[@ARBB1]

This is a fantastic little video! I'm part of a superbike building student team, do you think if it's feasible that we could make one of those? Thanks!

[@TimmaethBoy]

A real-world working version? Anything's possible, but it depends on how much time, money, and effort the team wanted to do something like that.

[@ARBB1]

​@@TimmaethBoy Yeah, so in our case we have a 2 year design cycle, and I suppose we'd plan to do something like this only in the next project, so there'd be 4 years! As to money, I suppose machining a lot of these pieces would be expensive, but we could make do. At least I'm very interested in seeing if we could pull it off 😊

[@halohat2286]

You should forward this video to Trackhouse Racing to assist them in their 2024 MotoGP initial season.

[@noral342]

Aprillia already have seamless shift!

[@halohat2286]

@@noral342 my suggestion is due to his expertise. He completely understands this engineering at a level a MotoGP team would value. And I'm going to go out on a limb and bet he understands more than just this subject. A lot more. He has smart written all over him, ha.

[@halohat2286]

I'm an old man now. Raced CCS at Willow Springs, Riverside and Carlsbad with the beginning of AMA Superbike legends when I was barely a teen. Then again when I worked for Honda in the very late 80's and early 90's in Phoenix. Fast but never enough money to do a season of AMA, which breaks my heart to this day because I was fast. I screwed up by just sitting there not knowing what to say when I had someone tell me "we are thinking of sponsoring you". That didn't go over well ha. If Trackhouse contacts you, be confident and again, be assured you have the skills to do anything. I know you do. And if you know, you know.

[@TimmaethBoy]

@@halohat2286 Very cool. I used to race with CMRA, but like you, too much money, and that's way before even considering a MotoAmerica event / season. I mainly race TMGP now - minibikes; they're such a blast, the events are way more laid back along with good people. Fyi, there's plenty of "old men" racing minibikes if you were wanting to give it a go again. :)

[@halohat2286]

@@TimmaethBoy if it can't do 160+ I'm afraid I'd fall asleep lol. I have issues still haha

[@revjimjones]

Any plans to release the STL? I think this would make a fun desktop display/ fidget toy.

[@TimmaethBoy]

More than likely won't unfortunately.

[@BestKosmakCZ]

Holy moly brother. This i s insane level of reverse engineering. Is there a way you could publish the 3D files?

[@steveman1982]

I'm trying to imagine how a downshift works. With upshifting I get that the higher gear will spins faster, disengaging the lower gear. But what allows the higher gear to disengage on a downshift, because I think in that situation the higher gear will still be the faster spinning one. With slipper clutches the downshifts do not need to be seemless I suppose, so there's perhaps some wiggle room there perhaps? So first disengage the higher gear and then engage the lower?

[@LaserFur]

The gap on the shaft to the sliders reverses the order of operations for downshifting.

[@dhushyanth-qh9qy]

Can u share the 3d model

[@billynomates920]

looks like there are more than 13 pages there - 15 at least.

[@user-xf1bv6wb1h]

So it’s basically an Italian scooter gearcross transmission used since the “ thirties” nothing new under the sun ?

[@Ray88G]

I've seen a similar mechanism in 70's and 80's bikes an scooters

[@filippostube6533]

1964 hodaka

[@__--JY-Moe--__]

good luck with it! this was filed @ the US PTO, not the JP PTO. looks nice! don't forget 2 add those ceramic bearings!👍 sounds like U'r on the fence about what the total mechanism drag/friction would be... good luck! some1 sponsor Tommy, with a steel BJ printer!! I hope U have a cad that does gears & stuff! not 2 jump way ahead! sorry!

[@tulio-a-cardinal]

It seems to me that this system would break if one were to downshift under acceleration or upshift under deceleration, is that so? Is there any provision on the design to avoid this issue? Since this is only to be used by the very best pilots in the world, it's probably reasonable to assume they would never downshift under acceleration or upshift under deceleration, but if this system were to be brought to road bikes, this would probably be a huge issue. Congratulations for your 3D modeling, construction, explanation and video.

[@MrNukealizer]

To downshift, the current gear has to disengage in the acceleration direction to engage the lower gear in the deceleration direction. Similarly, upshifting has to disengage the current gear in the deceleration direction to engage the higher gear in the acceleration direction. Thus the two gears can never both be engaged in opposite directions at the same time to bind up the gearbox. We haven't seen the springs that let the slides move on the shaft, but I suspect they each only go one way, so it would likely even prevent engaging a lower gear in the acceleration direction or a higher gear in the deceleration direction before the current gear disengages in the same direction. Even if it doesn't prevent that, it likely wouldn't cause any damage because the backs of the levers would be sliding on the gear instead of the tips catching it, resulting in just not shifting until the load is reduced. The main way I could see causing damage to the gearbox (ignoring potential engine damage from overrevving) by shifting that way would be putting more stress on the shifting mechanism to forcibly disengage the gear under load. But that also means the rider would notice it's taking much more effort than expected to shift, so they probably would reconsider before going too far.

[@tulio-a-cardinal]

I hadn't considered that the shift rods or slides (the very colourful parts of the model along the shaft) are the parts that put light spring pressure to disengage the previous gear under normal operation (upshift under acceleration or downshift under deceleration). It seems that this only works on the correct direction; on the reversed direction (downshift under acceleration or upshift under deceleration), there would be no spring to disengage the previous gear, and so the gearbox would probably behave the same as a regular gearbox: it would require too much force to operate under load. ​@@MrNukealizer, I think this is just another way of saying the same thing you just said. Thank you for getting me to understand this better, it is a very interesting mechanism. I just don't think I quite understood what you meant by the "backs of the levers sliding on the gears instead of the tips catching it", would you care to elaborate on that? Is this related to the fact that the shift rods or slides are operated as 2 separate groups?

[@MrNukealizer]

@@tulio-a-cardinal When I said "backs of the levers sliding on the gears instead of the tips catching it," I was talking about what would happen if springs on the slide let it engage two gears in the same direction at the same time. When shifting the normal way, the higher gear would take over when upshifting or the lower gear when downshifting, immediately letting the other gear disengage. If you shift the wrong way and the springs allow, it could try to engage a lower gear under acceleration or a higher gear under deceleration, which wouldn't take the load off the current gear to let it disengage. In that case, the little levers inside the new gear that are supposed to transfer power would just slide on the inside of the springy ring instead of engaging the gear, since the current gear is already turning the shaft faster or slower than the new gear. Thus there shouldn't be any damage even if it tries to engage two gears at once in the same direction when shifting the wrong way. But realistically that's very unlikely to actually happen because the slide springs would need to work in both directions, and I can't think of any reason to design them to do so.

[@Bata.andrei]

Actually the idea is not new. Zündapp ks50 had a similar transmission way back in the '70s

[@ThiagoMarquardt]

Bike hub gear works like this

[@ThiagoMarquardt]

With this gearbox, is impossible to downshift accelerating. Because have force in the rod. Only upshift accelerating and downshift desaceleraring.

[@GamezGuru1]

this is a great question, and from the info in this video, I think you're right. Pulling a downshift whilst even slightly on the throttle will cause the lower gear to be engaged by the pair of negative torque dogs, without releasing the higher gear. It's possible that the selection system is sophisticated enough to not destroy the gearbox though, but not clear from this 3d model...

[@halohat2286]

I hope you dont get upset with me. I forwarded a link to your MotoGP gearbox video to Trackhouse Racing's employment people. I think your video speaks for itself and im sure you know more than the video informs.

[@TimmaethBoy]

Not upset at all. I just do this for fun so I doubt anyone would take this seriously.

[@halohat2286]

@@TimmaethBoy You printed the gears too right? However understanding the function, patent in hand or not, and then both building the gearbox and explaining in detail its operation is next level. I also watched some of your other videos. I'd say you are definitely qualified to be a great asset of a MotoGP team. I've raced road race bikes as well as having worked on them. You have the skill to build, modify, trouble shoot and maintain several components of a MotoGP bike. Don't underestimate your skills.

[@TimmaethBoy]

@@halohat2286 You're correct; everything you see in the video is made from scratch. What racing org did you used to take part in? Appreciate the kind words.

[@halohat2286]

Oops, replied on a different set of comments of this thread ha. The one that says you should forward your video to Trackhouse...

[@knyffeler]

Honda just ripped off what Hodaka basically did with ball bearings 50 years ago.