How A Motorcycle Transmission Works

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[@tsubarider13]

Ok, I've watched many videos about how a transmission works in a bike and they always left me wondering.. This is the first video that gave me the full picture. Thank you for the excellent explanation.

[@faustinoeldelbarrio8967]

Finally! I have been looking for so much time into how transmissions work and most videos just state the obvious on gear ratios but never show the mechanical components. Today I can sleep in peace.

[@guitarchitech]

Thanks! Best visual for explaining moto transmission I watched so far

[@gksalf10]

2:01 “always a little bit of drag”, what a perfect demonstration! I thought the drag was primarily due to the fluid drag of engine oil in which gearbox is immersed…(correct me if I’m wrong) but now you showed me the drag is still present without the engine oil. It was primarily due to weak friction between the countershaft and freespinning gear! So this was why we feel the clunk when we put into first gear, after stopping in neutral for a while.

[@233kosta]

You get two lots of drag. What he showed is just from friction between gears and shafts. It's why when you lift up your rear end with the engine on, the wheel might start to spin. You also get drag in the clutch. Sometimes the plates are making light contact, and sometimes it's just viscous coupling through the oil. Either way, it results in your input shaft spinning in neutral, even with the clutch fully in. Then when you click it into first, that entire input shaft assembly comes to a sudden stop as the dogs crash together. The angular momentum ("angular" because spinny thing) has to go somewhere, and that somewhere usually ends up being the rest of the bike being lurched forwards. I believe this to be either intentionally engineered into the system, or at very least, intentionally not engineered out of it (except on really small engines, where such clutch drag would sap too much power, such as on many 125s). This is because the gearbox *needs* the shafts spinning at different rates in order to ensure the dogs can slide past each other. If both shafts were static, unless they'd stopped in perfect alignment, the dogs would crash into each other when you attempt to get into 1st, and you'd bend the shift fork before you get it into gear if you try to force it.

[@baxterenrife]

Excellent video. Some people just seem to be able to get it right and you are amongst them. Many thanks, very helpful.

[@KraeseRepairs]

I caught that one.. "when you shit, shift" lol

[@trieusonvn]

I like this gentleman's accent! Very clear

[@ZekeGraal]

I got my first bike Monday and was wondering about this. Thanks for the awesome demonstration!

[@propdoctor21564]

Excellent video !! I've been riding motorcycles for 40 years and always have been curious how the shift mechanism worked

[@HTMR]

LOL now this video will be in your head every time you shift.

[@tsuudon5017]

great vid! also helps with the mindset of shifting "properly" to actually understand how it all works

[@jerryjeremy4038]

This video is underrated. Amazing bro!

[@donb.909]

Clearly spoken and explained in detail, kudos, well done.

[@wesleymarkmusic403]

Very informative. Great explanation. Thanks.

[@sundo78]

incredible explanation. Thanks 👍

[@gschady]

every time he says "shift" take a sip of beer .. you'll NEVER finish the video!!!

[@NightWear21]

Excellent video! Thank you!

[@enockarmitage5535]

The explanation is excellent 👍

[@KensGarage1]

Nice job on that video. Thanks!

[@chrisstokley7687]

wow -great visual

[@CTmoog]

Great video man! It looks brand new. Thanks for showing us how it works!

[@HTMR]

Thanks Matt!

[@germancastrolinares9262]

The best transmission tutorial than I’ve ever see. 7:03 pegs = dog teeth Slot= recesses

[@truckertwotimes7189]

very interesting! thanks!

[@jbstepchild]

Perfect Ik there's more but as a basics this is perfect

[@bradrush45]

Excellent video!

[@1000sofusernames]

Great video. Sadly I think I'm in for a world of hurt...my gsxr has been jumping to neutral at high revs in 3rd. I imagine it's going to be a winter project with the engine out.

[@johnburkitt9428]

Nice cleanup. Honda CB750 is my project bike come fall and the engine needs to be rebuilt so thanks for making videos with great detail. Would be nice to have a step by step engine rebuild video on KZbin. Great job! 👍🏻

[@HTMR]

I'm working on a rebuild video for this engine. Both top and bottom end.

[@devarajm6540]

Excellent , 👍

[@jamesa6272]

That pvc pipe grease gun holder is genius!!

[@HTMR]

Yes they tend to drip and this collects it all.

[@itpugil]

07:04 "These dogs, when you're shit, when you shift...."

[@Dadmoves49]

Good vid man

[@HTMR]

Thank you!

[@stmurphy4356]

Hello, the video is great and instructive, I would ask you if you can give advice, I have a yamaha fz600s2 2009 that crashes a lot when I put in first gear and from first to second, it is also very audible from third to second, why is this happening people tell me that it is normal for that model, when the oil is cold then it is great otherwise I use FUCHS SILCOLENE COMP 4 10W-40. Hello from Croatia.

[@ankitbhai107]

Satisfying vdo😊

[@miamimotogroup5371]

Would of been nice to know which gear effects which gear your in. Like example i have 1st gear issues on a vstar 1100. Which gear ⚙️ would that be?

[@tapasmishra3246]

this is very close to what I wanted to watch. I want to see some animation video which explains shifter drum and gear fork working in more detail.

[@tapasmishra3246]

ok I have got one interesting video 2 minutes real view of how motorcycle transmission works kzbin.info/www/bejne/Z5qToYiha92kebs this is what I wanted to see. Commenting if some one else comes here they can see both the video for better understanding.

[@it_is_what_it_is_brotha]

That was great. Approachable to anyone

[@enrique7estrada]

Great video, I am in the process of rebuilding a kz650, any tips on what to look for as I reassemble the transmission into the crankcase?

[@HTMR]

#1 tip, bench shift it before further assembly.

[@beastboy7327]

Awesome

[@darkcrow5573]

Mr. can you make a video, about the connections of clutch and gears.

[@israel-hahadasha]

Great movie maann

[@humanisticdesignshuman8736]

I would like to ask regarding the video at the end, where the dogs of the gear slide in between the pins of the neighbour gear. why is there so much free play for the dogs to move? Would a new trans not have any free play here ?, or does it eliminate a knocking force generated by connecting two gears at speed with an added resistance torque.

[@billhenry7833]

7:05. “When you shit…”. Must be a powerful bike.

[@toribaltimore]

Excellent video! Q. Where does the clutch come into play? Is that when you're pulling the dogs away?

[@HTMR]

Clutch not installed in this video.

[@bog2k3]

the clutch disconnects the engine from the gearbox, allowing the gearbox to operate without any load, which makes it easier to shift gears. The dogs are engaged or disengaged by the forks controlled by the shifter

[@louisseaman8455]

When a transmission is stuck in 1st gear, what's more likely, the selector mechanism is jammed, or shift-forks are hung-up?

[@Fezzler61]

Thanks. Interesting. On the infamous CB500/500, what are let's say they top three transmission issues as they age?

[@HTMR]

Chipped or worn teeth/dogs. Bent shift forks. Bent shift shaft.

[@MrCoffeypaul]

Always wanted to know how these things worked, in the big engines they can seem to be very complicated but the basic principles got to be the same?

[@HTMR]

Pretty much the same for all motorcycles. Same principles.

[@Ben7Seven]

Nice video thx!! I have a question though, how come that the teeth on the sides of the shifting sprockets exactly engage with the recesses of the free wheelling gears when shifting while they spin rapidly with different speeds? How come you dont need something like a synchronizer ring as in a manual car transmission to match their speeds to connect them?

[@HTMR]

Because motorcycles have a constant mesh trans. Car gears are not meshed and need to synch up so they don't grind.

[@Ben7Seven]

@@HTMR Thx a lot for the reply! So as I take it, every shifting gear on the input shaft is constantly meshed to a free wheeling gear on the output shaft and vice versa, ok.. But every shifting gear engages with a wheeling gear right next to it on the same shaft, which is not meshed to it and therefore can have a different speed... as is the case when e.g. you shift from neutral into first gear, because in neutral the shifting sprocket for the first gear is not moving at all but when you shift into first gear its moving and transmitting power because it is locket with its wheeling gear ... and I feel when they meet they should be matched somehow which obviously is not the case because it works very well... thats what I mean.. I dont want to get on your nerves though (:

[@gksalf10]

@@Ben7Seven 6:55 The actual parts that engages each other are dogs and slots. They are not delicate mechanisms like the gear teeth…only 4-5 dogs in a whole circle, with big blanks. They are quite tough because of their simple shapes, so they will withstand wear and collision during normal shifting, if not put in high pressure. There is no guarantee that, when you shift, the slot is exactly positioned for the dog part. I think there is about 30-40% chance that the slot is initially blocked. But since all those parts are spinning, the discrepancy will be resolved in a blink. Actually, this is the primary reason that we shouldn’t be stopping at high gear. It often get stuck at false neutral when we stop in 4~6 gear and then try to shift down to the first. It’s that 30-40% chance of dogs not fitting the slots!

[@Ben7Seven]

@@gksalf10 Thx a lot for your clarification! makes sense..

[@bog2k3]

in a car transmission, the dogs are much smaller and thinner and close together, so they can't mesh while spinning without the synchros. In a motorcycle tranny the dogs are wide apart and are able to mesh directly. This makes it possible to shift without the clutch, but is more noisy than a car tranny.

[@vedq5TVvideo]

Nice video, when you say sequencial you can't go from 1st to 5th gear right you must do 1nd, 2nd, 3rd,and 4th also if you shift down you also do sequence like 4,3,2,1 right?

[@HTMR]

Yes

[@bradballard2068]

What makes a transmission difficult to get into neutral. Or should I ask what adjustment is needed

[@Kuhtlass]

7:06 - must be a crotch rocket thing😜

[@mikicoal]

How do the dogs engage if they're not lined up when you shift (which they probably won't be). Do they just slide until they do line up and pop in? If so, then it's obviously relying on the transmission of power from the wheels either to the dog gear on the output shaft or the free gear on the input shaft. In that case, how do you get it into first gear at standstill? Is that purely from the residual power of the engine?

[@truckertwotimes7189]

the clutch lets you put it in first from a stand still

[@mikicoal]

@@truckertwotimes7189 Yes, but how. If the dogs aren't aligned when you engage the clutch, how does it let you get into first? (Not a rhetorical question by the way).

[@kungfu2toe]

Great Pro Video! hey matthew, was hoping you could explain why tranny gets stuck in 2nd on a klx 110? probably a bent shifter fork? Thanks matt! who's gonna crack my case?

[@HTMR]

I'd start by taking the RH cover off and taking a look at the shift detent mechanism.

[@kungfu2toe]

@@HTMR I had it down to the shift drum key/shift detent mechanism. it was stuck in 2nd. I took the washer off then worked it back and forth with a hammer and prybar... ouch! Bam it came free after about 15 mins of prying and bangin. lets hope it didnt mess anything up! ITs shifting now! I should have took a video. Thanks Man!

[@littlewing60]

where did you get the socket your using at 1:04 and whats the name of that type of socket

[@HTMR]

Motion pro...I forgot the pn. I'll double check.

[@HTMR]

Here is the link amzn.to/35HKb6U

[@theblackparaders]

Really quick question here as i am concerned. If i were to shift from neutral to 1st gear, and didnt shift hard enough to 1st and felt a clunk and the gear lever was "kicked" back into neutral, will it do any damage to the gear dogs or gear teeth? Have done it a couple of times to my bike and probably shifted too lightly.

[@raphy_tt]

It *would* do damage but nothing serious for a now and then mistake, though it’s a habit you should break and try practicing getting the shifts consistent and enough but not too much pressure 👍

[@theblackparaders]

@@raphy_tt Alright, will take note from now on, and work on it. Thanks

[@karutatv5515]

new subscriber here...

[@Altruistic00]

Do the dogs get damaged over time from using quickshifter/clutchless shifting? Will using the clutch avoids damaging the dogs at all or will it only lessen the damage effect to some extend? (way less compared to using qs/clutchless)

[@HTMR]

Yes, they wear over time. I would say violent shifts would be the worse on the dogs. Quickshifters/clutchless shifting can be just fine if performed correctly.

[@Altruistic00]

@@HTMR Thanks. I've just finished watching The Workshop video on quickshifters. What you said checks out & also I found out apparently low engine speed shifts is not good for quickshifters.

[@RidhinR-mt3fr]

ബ്രോ ഇന്നത്തെ വീഡിയോ പൊളിച്ചു സൂപ്പർ 👍👍👌

[@lucaric6935]

whats the main cause for bent shift forks. I accidentally shift few times from 1st to N instead of 2nd(40kmph) then I shift back to 2nd, and theres clunck sound, thoese it really bad for shift forks?

[@HTMR]

Shift forks bend usually when the shifter is forced. The clunking you heard is the dogs engaging on the gears as they meshed.

[@TheGearhead222]

I remember owning a BMW R71 replica that had no synchronizers, which was a big deal for WWII American bikes. My 1963 Falcon had no synchros in first gear. Any comments concerning this? John in Texas

[@HTMR]

I don't know of any motorcycles that have synchros.

[@kristapsjj8520]

I was wondering whether anybody has added gears to motorcycle gearboxes. Like adding a 7th gear for highway speeds to lower the rpm, for fuel efficiency Or do they change gear ratio?

[@truckertwotimes7189]

that's what i've been looking for, i think it would be possible to change the 4th gear on my 07 Honda Shadow VT600CDA and give it an even bigger gap between 3rd and 4th to allow for less rpm's at 80 mph 🤔 what do you think?

[@crazygaming4669]

Can I know why bike never goes back when we start it why the engine rotates in same direction how can it rotate in same direction

[@taylorpreston8502]

Hi, when i went to ride my bike the other day the gears wont shift when moving or stationary. Im not sure why its doing it as i was out on it just hours before and it was fine. Any ideas of how to fix it? Thanks

[@HTMR]

Year make model?

[@taylorpreston8502]

@@HTMRlexmoto isca 2020

[@HTMR]

@@taylorpreston8502 I don't know that model at all. Pull the RH clutch cover off and see what the mechanism is doing.

[@SuperRider-RS]

I have triumph triple motorcycle, there is always clunky shift from 1st to 2nd to 3rd, it is never smooth, what could be the problem? Synchroniser issues?

[@HTMR]

Motorcycles do not have snychronizers. I have ridden a few triumphs and the transmission are never as smooth as other makes. Is the clutch in good shape?

[@SuperRider-RS]

@@HTMR it’s a new motorcycle just a month old, clutch is fine, just there is bang in shift from 1st to 2nd to 3rd and I been told triumph makes bike like this and it’s the bikes character :( why can’t it be smooth is my question to the Triumph

[@mahamajones2994]

Good job but I was expecting an explanation of the various gear types(1-5)

[@shadrecto4611]

Very informative content... But I have a question. What if you accidentally shift your gear up, without pulling the clutch. Could it damage the transmission? Can anyone answer this question? 😅

[@HTMR]

Nope, just let off the throttle and shift up. I do it all the time.

[@oscarm9473]

Obvious

[@shadrecto4611]

@@oscarm9473 what do youean obvious?😅

[@oscarm9473]

Obvious the transmission is damaged

[@shadrecto4611]

@@oscarm9473 should I replace it with new transmission? I didn't mind to have a check it up on the motorcycle dealers, since my MC runs in good condition so far.

[@bluecollarbiker8005]

So how dose a 6speed work with overdrive is overdrive electric

[@mklaver31]

No, with overdrive the input gear is larger than the gear translating to the output gear, therefore making the output spin faster than input. If that makes sense. Anybody please correct me if I'm wrong.

[@mklaver31]

Don't worry if you don't understand it though, I'm still having a hard time grasping some of it.

[@lakaarane1984]

What engine is this

[@HTMR]

74 cb750

[@zkryazkrya3118]

Hello, I want to send you a picture of a bike gear and inquire about something

[@joelcowan2568]

Why not show the different paths for each gear

[@stephanopapadimitriou4789]

So motorcycles have sequential gearboxes

[@fingerscrossed2317]

You almost said, and when you shit 😅😮👍😆😄

[@rolandezdramat1013]

Thank you for the info... But why yu have to talk about "when we shit" 😂😂😂😂😂😂😂

[@jay-cu9kj]

How the engagement is done without interrupting the teeth?

[@pheirphon4680]

Did you say shit and not shift?😂

[@VOX-TRO]

When I what? 7:05

[@rodolfoteguihanon6842]

FLM FOR PRESIDENT 2022

[@richkennedy3134]

I thought this was terrible. The first part, you don't see the gears on 1,2, grabbing anything because they are below...I'll stop there. It's just not easy to show. But a good try.

[@HTMR]

By all means, grab a camera and try and do a better job and post it for me to comment on.

[@zkryazkrya3118]

Do you have a Facebook or WhatsApp page?

[@pooperdigman8064]

I finally found a vid that show how it’s done. All the other ones are weird animations with a voice that bores me to sleep or it’s a weird european that can’t talk

[@txtermm]

Great video!

[@HTMR]

Thanks!