I've got a manual Honda bike, but i've always been baffled about how manual motorcycle gearboxes work.. you've explained in . a clear and precise way well done
excellent explanation, I've seen a couple of videos but couldn't see the entire picture, with your video I was finally able to 'see' how everything comes together.
Adam Goodburn Thanks for the very flattering comment. I'm moving to a newer, bigger workshop at present, and then more videos will be coming out. This and other videos will be expanded on in the future thanks again - matt
Absolutly Brilliant Matt! Perfectly satisfied my need to understand gearboxes. I've got a, badly treated, 94-97 VFR with a ropey 2nd gear. I need to understand everything involved before I can properly diagnose. Thank you :-)
No worries mate, thanks for the comment. I need to finish recording the next part to the gearbox series which is the selector mechanism. Thanks again - matt
Thanks very much, and thanks to everyone for the nice comments. Hope the video helps. I'm in the process of doing a series on 2 stroke engines. Basically I have a built up engine and I'm going to dismantle it from top to bottom and go through as much as I can about how it works and how its designed and why. Should be released in a week or two. - matt
mate, thank you so much for this video. Studying transmission at the moment, and it seemed massively confusing until now. Really appreciate this video!
No worries mate, thanks for the comment. If it helps someone out then it's worth doing. If you have any other questions or even a subject you'd like to know more about I might be able to make a video to help you out - matt
Gear position swaps between 3-4 or 4-3 can be down to a few factors, mostly to do with selector drum design. Depending on how the input/output shaft are orientated within the gearbox dictates where the selector forks are situated. Sometimes this means switching what orientation the gears are. Other design reasons can be torque loading on the gear shafts. So for example having the order 3-4 can sometimes cause unwanted vibrations in the transmission, switching them can reduce this to exceptable levels. Hope this helps. - matt
Great video. This has helped me understand my gearbox in my lt500. it has a full 1-3 override auto shift. I have been told without custom shafts and gearset it cant be a 1-4 full auto. Now I know why! Its used for 300ft sanddrags.
I think I know what your problem could be the manual states "Assembling the transmission components Place the clutch-side (right) half crankcase on a support, then fit the spring and the gear indicator ball in their housing (see figure) after smearing them with a little grease so as to prevent them from coming out. Fit the thrust ring (0.6 mm in thickness) on the driven shaft (1). Apply a little grease to the ring to keep it in contact with the low gear. Fit the driving (2) and driven shafts (1) together and position the fork on the former (3). Place the assembly in the crankcase." Basically theres a ball bearing and a spring that run along a detent track, if the ball has popped out then the selector drum can shift on its own sometimes. All the gearbox has to be assembelled in 2nd gear - the manual states "Also check that, when the desmodromic shaft is positioned on the 2 nd gear, the cam rollers are at equal distances from the fork lips. If not, gently distort the spring ends until the desired situation is obtained."
Will the whole mechanism still work if the input shaft is rotating at the opposite direction ? Actually, I'm making a project and going to install the gearbox to a motor rotating the shaft. What I want to ask is whether the mechanism will act as reverse when I change motor's polarity. Or will it not work at all?
thanks for the really good thorough explanation. learned a lot. very keen to see your vid on the selector cylinder, but think I can actually work it out from what you explained here. top work! can you help explain how this type of transmission allows clutchless shifting? I'm fascinated how this is so easy to do. many thanks, keep up the amazing work. T
Hi, excellent videos. If it would be possibel to replace gears sprockets with slightly different jumber of teeth for example on clutch axle -1T and on the opposite side +1T in attempt to get more torque from the engine, would it be a must to remap the engine's computer? I think I need more torque on Kawasaki Z650 2019 and this was on my mind for some time. I bought a front chain sprocket with -1T and on next chain replacement I'll replace the chain sprocket to one teeth fewer one just to get the punchier machine run and some more torque but my concern is would that increase the chain wear and vibrations because the radius is smaller so the chain warps more around it. Have you any advices on this topic? Why would I want more power from such a light machine, well I like riding steep uphill hilly roads and quite often I just have to shift down and I have a feeling it would be much more smoother ride if the gears were set up more on the torque side. Top speed is not my priority. Good luck, thanx.
Wow, this is the best explanation I've seen so far (and I've watched a number of these), but I still have some questions. To start though, I'll put down what I came away with. On a 5 speed, 1) There are 5 gears on the input shaft and 5 gears on the output shaft 2) All gears on one shaft are constantly messing with gears on the opposite shaft 3) Fixed gears always mess with freewheeling gears on the other shaft 4) 1st, 2nd, and 3rd gears (1st, 3rd, and 5th gear measured from center of bike) on the input shaft are fixed and 4th, and 5th gears ( 2nd and 4th from inside) are freewheeling 5) Therefore, on the output shaft, gears 1, 3, and 5 are freewheeling and gears 2 and 4 are fixed 6) The dog gears are always on the side of fixed gears Right so far? I can tell from reading the comments on all these videos that everybody is fascinated with how you can shift without using the clutch. So what happens when you pull in the clutch. It disengages the driveshaft from the input shaft and the input shaft should start slowing down to a stop. Right? Questions: How fast does this happen? Is it in a second or two or much longer? Does what gear you are in effect the speed of slow down? Why would it stop spinning at all except if in neutral? Wouldn't the output shaft keep it moving (assuming the bike is in motion)? To continue, the input shaft has now slowed to a stop, causing the freewheeling gears on the output shaft to also slow to a stop. However, the output shaft is turning with wheel rotation speed, so all the gears fixed to the output shaft will still be spinning? Right so far? So when a shift is made, the rotating dogs are going to clash with cavities in side of the slower moving freewheeling gears. This is why the tops of the dogs in your video were ground down somewhat. So, I'm not sure how clutching even helps. (?) If you DON'T clutch, the input shaft is still spinning, as is the output shaft. Again when you shift, you are going to have a clash between dogs and dog cavities. In fact, because both shafts are spinning, it seems as if the shift would be smoother. (?) I feel like I am almost understanding this, but not quite.
Hello mate, this is going to be a long one lol "So what happens when you pull in the clutch. It disengages the driveshaft from the input shaft and the input shaft should start slowing down to a stop. Right?" No. - the clutch disengages the clutch basket from the clutch boss which is attached to the inputshaft if we're being technical. Here this might help - ua-cam.com/video/d74A37h4v6c/v-deo.html Seondly the inputshaft slows down yes but not very much as the you change gear and then engage the clutch again. The clutch is used to disconnect the inputshaft from any torque thats applied to it. When the next selected gear is engaged the shaft has no resistance to this change, and it would if the engine was apply a torque to it. "Questions: How fast does this happen? Is it in a second or two or much longer? Does what gear you are in effect the speed of slow down? Why would it stop spinning at all except if in neutral? Wouldn't the output shaft keep it moving (assuming the bike is in motion)?" Yes - I kinda answered this one above. "To continue, the input shaft has now slowed to a stop, causing the freewheeling gears on the output shaft to also slow to a stop. However, the output shaft is turning with wheel rotation speed, so all the gears fixed to the output shaft will still be spinning? Right so far?" Again the inputshaft doesn't stop. "So when a shift is made, the rotating dogs are going to clash with cavities in side of the slower moving freewheeling gears. This is why the tops of the dogs in your video were ground down somewhat." - correct, the dogs are the feature of a gear that experiences the most wear. These gearboxes aere called constant mesh, if you hear grinding then its the dogs chattering not the teeth of the gears. "So, I'm not sure how clutching even helps. (?)" I stated above that the clutch is used to disengage the shaft from the torque that is applied to it. "If you DON'T clutch, the input shaft is still spinning, as is the output shaft. Again when you shift, you are going to have a clash between dogs and dog cavities. In fact, because both shafts are spinning, it seems as if the shift would be smoother. (?) " Good question - you half of it right. Both shaft will continue to rotate as you engage the clutch, but they will deaccelerate. The input shaft will 'freewheel' as an entire assembely. The output shaft on the other hand will reduce speed due to the friction between the road and the tyre which the output shaft is connected to. This is turn is connected to the input shaft as they are constant mesh. So the gearbox reduces speed at the same rate the rear wheel (which is no unpowered) will. If you think of it like this. If you pull your clutch in the bike will roll to a stop no matter what gear your in. Anyroad, when you select another gear and release the clutch you continue on your way. Basically your disconnecting the power from both shafts this means there is less resistance when you mesh dogs together. The 'impact' between the meshing dogs is alot lower. Clutchless shift means that the impact is much greater, this reduces the life of the gears. Another way to think about it (very loose analogy) is changing gears on a push bike. If you are climbing a hill and change gear and putting your back into you hear a horrible clunking and you can feel the change is rough. Hope this helps - if not I'll do a video on making gear change and clutchless shifting
Thanks for that response! I understand about the clutch, etc. So when the clutch is pressed in, the input shaft keeps rotating but without the torque it has when not engaged? It is then the case that the input shaft's resistance to matching the output shaft is just the inertia in the shaft itself and not the inertia due to the pistons, etc.? It's the resistance to the "shock" of the dogs engaging that is important and not so much the speed differential between the dos and dog recesses? Is that right?
I just had a bit of an insight. Damage to the dogs and recesses can be done not just by normal grinding on the end of the dog, but also by the shock when the dog hits the end of the recess. This shock can be minimized in two ways. 1) By using the clutch to disengage the input shaft from the engine, thus reducing the resistance to turning of the gear with the recesses or 2) By matching the speed of the freewheeling gear to that of the fixed gear with the dogs. Shifting without clutching involves this latter method. If you were perfect at matching the speed there would be even less shock than when the clutch is used. Is that right?
lol yes mate, the problem with clutchless shift is that we're human, and can't perfectly match the speed of the two shafts. You got to remember that the speed of the shaft is the macth speed of the gear you WERE in not the speed of the shaft you want to be in when the engage the next gear. Think of torque as energy. When you disengage the clutch the energy tranfers form the engine into the input shaft diappears. Its motion is now 'powered' by the inertia stored in the shaft. When you select the next gear the impact (energy transfer) between the dogs and the recesses comes from the inertia in the shaft. If the engine was connected to the shaft when the shift takes place the torque (energy form the engine) is transfered into the dog recess throught the dogs on the moving gear. This results in higher impact energies cause more stress on the gear moving and the gear being selected. This is why gears are hardened, they behave like the impact anvils in a impact gun. If you can do something (use your clutch instead of clutchless shifting) this will prolong the life of your gear box.
Pony Power I think I've got it! In theory (although not in practice), someone could match the dog gear with the dog recess let the dog pop in and then minutely increase the speed of the dog gear so that it would just softly press against the front of the dog recess resulting in the perfect shift!
you would have triple the viewer if it counted each view individual per person . im going to need to rewatch this about 100 times ! thanks for the info mate cant wait to see your finished kawasaki
+hoggath hogg thanks for the comment dude. Yeah the kawasaki is coming along (slowly that is) I've seen alot of the gerabox videos on youtube and they don't quite go into what actual goes on inside. There will be some more videos related to this series, car gearboxes etc - cheers for the comment - matt
Outstanding explanation, thank you for sharing. I'm gathering as much information that I can before diving into a ktm 525 gear case that has a problem with going into reverse. I'm working on a 2008 polaris outlaw 525 (atv). Your video helps to build my confidence. Any advice on my situation would be greatly appreciated. Thanks again!
Thanks for your comment, much appreciated. Give me more information and I'll see if I can help. Is your problem physically engaging reverse or problems whilst in reverse i.e keeps slipping out of gear? thanks again - matt
The only information I have is that from the previous owner. The atv was in reverse and high centered on a rock when he hurt a loud clunk and the engine stopped running. The atv performs normally in all forward gears, it's only when you shift in reverse the engine stops after moving less than a foot. The atv is difficult to get back into first gear but once there it begins operating as normal. I'm currently in the process of taking the engine apart to see if I can find anything that's obviously broke. I'm having to wait for a few special tools to arrive before I'm able to get inside the engine. Thank you for the reply.
Dear all, does anybody knows why some motorcycle gearboxes have the following gear order, starting from the clutch: 1-5-3-4-6-2, and others: 1-5-4-3-6-2? Which is the reason to change the 3rd and the 4th gears position?
Hello Matt. i really like your videos about gearbox, overdrive and sprockets. learned a lot from them. i have a small question. these specs are from a CBR manual. primary reduction ratio: 2.117 1st gear ratio: 3.307 final reduction ratio: 2.600 so let's just say we are in 1st gear and we need to find how many times crank rotates for one revolution of rear wheel. can we find it by final reduction ratio*1st gear ratio* primary reduction ratio ? so in that CBR bike it's, 2.600*3.307*2.117 = 18.2 is it right ? thx a lot. keep it up 😊
No. The first ratio is a reduction. I.e a drop in speed, increase in torque. Do you usually convert the rpm and primary to just an input. So you take say 10,000 rpm and / 2.117 to get 4,724. This is your input.
@Njato Andrianarison Definitely YES, you need to clutch to reduce wear and tear on the dogs. Pulling in the clutch disconnects the engine from the gearbox's input shaft. This will reduce the input shaft's rpm which in turn reduces the pressure/friction on the dog teeth when they disengage from one gear (say 1st gear), and it also reduces the slamming force on the dog teeth as they slide into the next gear (2nd gear). You can certainly change gears without clutching by closing the throttle just before you shift. This method will also reduce the gearbox input shaft's rpm, but not as much and as quickly as pulling in the clutch, which means you have a little less wear-tear protection of the dogs compared to the clutching method.
I have a Malaguti dune 75 ks with a AM6 engine and i have a problem ,i can't change into third gear it only goes in first,neutral easy with no click and sometime in second gear and sometimes it drops from second into neutral,what could be the problem
Downshifting is more damaging than upshifting generally. Your clutch is used to reduce the speed and torque when switching between gears, if you don't use your clutch and change gear at the same rpm as you normally would this increases the amount of impact between the dogs and their respective holes. In general this reduces the lift* (I mean life) of the gear set.
Aashwin Varshney when you downshift you increase the load on the engine, this is called engine braking. As for why downshift, simply because your over-ranging the gears (if that's a word) i.e your subjecting that selected gear set to speeds/torque from a very low load and speed. Its like jumping off a bus and trying to run to maintain 30mph. As for lift I meant to say life lol - thanks for the comment - matt
the engine is from a 1998 Kawasaki KX250 2 stroke. - "how it´s the axial distance between the shafts?" not sure what this means? If you asking what is the distance between the input and output shaft - I don't know off the top of my head, and I don't understand why you would want to know???
My ktm duke 125 keeps jumping from 2nd to neutral, 4th to neutral and maybe 2nd to 1st...its quite scary sometimes, should i replace the whole transmission or leave it to a mechanic?
+Dakota Rising You probably won't have to replace the whole transmission, if you look at this video ua-cam.com/video/UjaNXrcU3BA/v-deo.html at 9:20 onwards you should have a good idea whats going on it probably one of your springs has given up the ghost so to speak hope this helps if not just ask - matt
Hello mate, I'm abit unsure what you mean? The torque and speed are changing depending and how much you rev the engine. If you can be more specific then I can help - matt
I have a 2009 Triumph SE. Recently, I have serious problem to shift to neutral. When i stop for traffic light and in first gear, try to shift to neutral, I always shift to second gear no matter how careful I shift. Then I try to shift from second to neutral, it become so hard to press the gear shifter down, so I jammed in second gear..... If I successfully shift down , 90% I shift to first. Neutral just become so hard to engage. Why this happened? I own the motor for over 7 years, and I never had any problem to shift to neutral till recently. I don't have any problem to shift to any gear when bike is moving. Anyone know what went wrong? Any parts I may need to replace?
Hello mate - right so I've had this problem in the past only not with a Triumph. Simple things first 1) It can be your clutch cable. Usually the culprit (9/10 times) Over time the clutch cable will stretch, this causes the clutch to not disengage fully. Which means your input shaft has torque applied to it. This will cause your gearbox to 'ride over' the neutral detent. Firstly adjust your cable tension, if that sorts your problem you can run with thta or buy a new one its up to you. 2) Your using the wrong oil. Triumphs are easily pissed off with lower quality oils. Again this is a clutch problem. Cheap olis usually don't conatin sexy friction modifiers which help your clutch slip when. The oil misbehalfs when it get to higher temperatures. Use recommended oil that Triumph specify. 3) This is less likely but depends of the milage of your machine. Your steel plates are beginning to warp - again a clutch problem. This can cause your clutch to stick together and yet again not seperate properly. In summary its a clutch problem, not without a doubt but 99%. Try set 1 first and go from there. Adjusting your clutch cable should give you some result. I.e better or worse. Message me back if you have any problems or a success Hope this helps - matt
For people who don't know BMW offer an endurance transmission when you purchase a GS, usually at no extra cost. The difference is the gear ratio for 1st gear. The rest (as I understand it, unless the new model is different) are the same. The whole point it is to give the the ability to poddle around in 1st gear without reving the crap out of the engine. Basically you can pull away in first without using the throttle. This can help if the rear wheel slips when off road. This is an option with the big cc BMWs mainly due to their weight. With a different ratio for 1st, more speed is converted into torque. This allows the bike to 'push' the heavier bike at low revs. This is not needed for off-road bikes because; 1. they're lighter so less torque is required to move the lighter mass 2. they already have a gearbox ratio set-up for off-roading The GS is a road bike which also has the ability to do abit of off-roading. If you buy the bike to do mostly off-roading they will switch out the 1st gear set for the 'enduro' set. They reason why it doesn't cost anything is because they're just switching out one gear pair. 1 less tooth on the input gear and an extra tooth on the output shaft. Hope that helps Matt
+Pony Power yes my cbr f4i motors starting to get to the really in need of a rebuild poing and the transmissions all grindy in nuetral at idle speed, i put a new clutch in her but its still clackity, i was thinking it be something to do while rebuilding
ah right, any bike can have the selector changed to say 6 down for example but it means changing the selector drum. This isn't something you can just do and they don't sell them as aftermarket parts. If your gearbox is grinding in neutral then you have a selector issue. In a working gearbox the when in neutral everything should be free-wheeling. Are you sure its coming from the gearbox?
I'm still trying to understand why you don't need to use a clutch to shift. Are the dogs on the dog gears on one shaft all aligned? Never mind, I can see they are not. I still can't understand why a clutchless shift is smoother than one using the clutch.
Excellent! I've watched most of the videos on motorcycle transmissions and read lots of the comments and there's a repeating conversation that goes like this: Commenter 1 - If you can shift without a clutch then why even have one? What are you giving up? Commenter 2 - It will harm your gears if you don't do it right. Commenter 3 - I've been doing it for years with no harm and besides it is easy to do right. Commenter 4 - You only need the clutch for starting in first gear. Old buses and lorries (trucks) used to only have a clutch for starting. Commenter 5 - I use the clutch on the 1-2 shift because neutral is between them and that makes it harder. Commenter 6 - I don't use it for downshifting. You can jerk the bike if you do that. Commenter 7 - I do it even downshifting. No where is part one of the original question answered. I hope your video does that. My best guess now is that it involves speed matching -- not of the adjacent gears necessarily but of the rotation of the input and output shaft, or maybe that amounts to the same thing.
+cRizy89 I don't know what your asking, but I think I know what you mean. Dogs are fitted to both car and bike transmissions, cars tend to have synchro rings which is abit more complicated but the idea is the same. Gear teeth are precision cut features, people think that the gears engage each other and change location when a shift is performed. This would quickly wreck the gear surface and make shifting impossible. Dogs are more robust due to their simplicity. Changing gear using the clutch or without doesn't effect the way in which gear are selected. And another point which I get asked alot, clutchless shifting damages your gearbox.
+Pony Power Ohhh I see. Then why is clutchless shifting more acceptable to be performed on bikes then it's in cars? I saw a video in which it stated that due to having a sequential gearbox, clutchless shifting is possible (or a natural/normal thing). That's why I started watching your videos trying to find an answer as to why this is acceptable thing, by a large amount of people, for these types of gearboxes. By the way, on my original comment, I meant the wider dog recesses, rather than being a dog recesses just big enough for the dogs, without any further room (I did understand your answer though).
The Workshop raced a 2005 YZ250 last year and had to replace 3rd and 5th twice plus a selector fork It was the dogs kept wearing away within the space of a few months And the RM liked to round of 2nd gear
Will the whole mechanism still work if the input shaft is rotating at the opposite direction ? Actually, I'm making a project and going to install the gearbox to a motor rotating the shaft. What I want to ask is whether the mechanism will act as reverse when I change motor's polarity. Or will it not work at all?
Will the whole mechanism still work if the input shaft is rotating at the opposite direction ? Actually, I'm making a project and going to install the gearbox to a motor rotating the shaft. What I want to ask is whether the mechanism will act as reverse when I change motor's polarity. Or will it not work at all?
+Ankur Ralhan sorry for the late reply, google marked your comment as spam for some reason? Anyroad, yeah the mechanism work in both directions apart from the selector drum. So changing gears has to be the same way. Good gearboxes if your wanting to use them for a lathe or milling machine, can easily take the torque. Hope this helps - matt
Excellent video, nobody else goes into as much detail (which then makes it so much harder to understand). Thank you!
Thanks for the comment, glad I could help. - matt
I've got a manual Honda bike, but i've always been baffled about how manual motorcycle gearboxes work.. you've explained in . a clear and precise way well done
Constant mesh gears were always a complete mystery to me. You've lifted the veil Matt, many thanks...
excellent explanation, I've seen a couple of videos but couldn't see the entire picture, with your video I was finally able to 'see' how everything comes together.
After just 5 minutes I learned so much. Fantastic video mate.
A hands-on experience for us. Thanks for breaking it down with detailed demo.
No worries mate, there's also the other 2 parts which cover the selector drum and the gearshift mechanism - matt
No worries mate, thanks for taking the time to write a comment - matt
I don't usually comment on videos, but I had to say thanks. All the videos I've seen of yours are excellent! Please continue making them!
Adam Goodburn Thanks for the very flattering comment. I'm moving to a newer, bigger workshop at present, and then more videos will be coming out. This and other videos will be expanded on in the future thanks again - matt
That was an awesome explanation! You've really made it clear. Thank you so much. I'm looking forward to watching the rest of the series.
Absolutly Brilliant Matt! Perfectly satisfied my need to understand gearboxes.
I've got a, badly treated, 94-97 VFR with a ropey 2nd gear. I need to understand everything involved before I can properly diagnose.
Thank you :-)
No worries mate, thanks for the comment. I need to finish recording the next part to the gearbox series which is the selector mechanism. Thanks again - matt
Awesome, I completely understand this whole system now. Thank you so much!
Fantastic detail & explanation you have removed the fear factor. Keep up the good work :)
Glad this video could help, like I stated in the video there's nothing to them really, its just a bit baffling when you first open one up. - matt
Excellent video mate I ever watched on manual transmission! Your knowledge is rock about transmission and other stuff. Regards,
Thanks very much, and thanks to everyone for the nice comments. Hope the video helps. I'm in the process of doing a series on 2 stroke engines. Basically I have a built up engine and I'm going to dismantle it from top to bottom and go through as much as I can about how it works and how its designed and why. Should be released in a week or two. - matt
Fantastic vid. I'm about to pull down a Montesa Cota 242 gear box, now I have some idea what I'm looking at. Thanks so much. Justin
Very informative and detailed. Thank you!
mate, thank you so much for this video. Studying transmission at the moment, and it seemed massively confusing until now. Really appreciate this video!
No worries mate, thanks for the comment. If it helps someone out then it's worth doing. If you have any other questions or even a subject you'd like to know more about I might be able to make a video to help you out - matt
"locked to the shaft" that what make me understand whole operations. And why no other videos explain this thing?
Great video btw!
This video is absolutely fantastic.
Gear position swaps between 3-4 or 4-3 can be down to a few factors, mostly to do with selector drum design. Depending on how the input/output shaft are orientated within the gearbox dictates where the selector forks are situated. Sometimes this means switching what orientation the gears are. Other design reasons can be torque loading on the gear shafts. So for example having the order 3-4 can sometimes cause unwanted vibrations in the transmission, switching them can reduce this to exceptable levels. Hope this helps. - matt
Thanks a lot, Matt.
***** No worries mate.
Nice
Very well explained, thanks
Great video. This has helped me understand my gearbox in my lt500. it has a full 1-3 override auto shift. I have been told without custom shafts and gearset it cant be a 1-4 full auto. Now I know why! Its used for 300ft sanddrags.
Thanks for the comment dude happy the video was useful - matt
Incredibly well explained. Thanks a lot!
Thanks for watching - matt
I’d love to meet the genius who thought of this system. engineering is amazing
Fantastic Video !!!
Thanks for the comment mate, happy this video was instructive - matt
I think I know what your problem could be the manual states
"Assembling the transmission components
Place the clutch-side (right) half crankcase on a
support, then fit the spring and the gear indicator ball
in their housing (see figure) after smearing them with
a little grease so as to prevent them from coming out.
Fit the thrust ring (0.6 mm in thickness) on the driven
shaft (1). Apply a little grease to the ring to keep it in
contact with the low gear. Fit the driving (2) and driven
shafts (1) together and position the fork on the former
(3). Place the assembly in the crankcase."
Basically theres a ball bearing and a spring that run along a detent track, if the ball has popped out then the selector drum can shift on its own sometimes. All the gearbox has to be assembelled in 2nd gear - the manual states
"Also check that, when the desmodromic shaft is
positioned on the 2 nd gear, the cam rollers are at
equal distances from the fork lips. If not, gently
distort the spring ends until the desired situation
is obtained."
Best explanation on the web
Cheers dude - matt
absolutely thanks for sharing this. awesome video man.
No worries mate thanks for the comment - matt
This is an amazing video. Thank you.
Thanks for the comment mate, if you have any other video ideas etc then please feel free to write a comment, that goes for everyone - matt
Will the whole mechanism still work if the input shaft is rotating at the opposite direction ?
Actually, I'm making a project and going to install the gearbox to a motor rotating the shaft. What I want to ask is whether the mechanism will act as reverse when I change motor's polarity. Or will it not work at all?
Thank you very much,great video
Very good video,thank you.
Superb video, bravo
thanks for the really good thorough explanation. learned a lot. very keen to see your vid on the selector cylinder, but think I can actually work it out from what you explained here. top work! can you help explain how this type of transmission allows clutchless shifting? I'm fascinated how this is so easy to do. many thanks, keep up the amazing work. T
Very good presentation
Hi, excellent videos.
If it would be possibel to replace gears sprockets with slightly different jumber of teeth for example on clutch axle -1T and on the opposite side +1T in attempt to get more torque from the engine, would it be a must to remap the engine's computer?
I think I need more torque on Kawasaki Z650 2019 and this was on my mind for some time. I bought a front chain sprocket with -1T and on next chain replacement I'll replace the chain sprocket to one teeth fewer one just to get the punchier machine run and some more torque but my concern is would that increase the chain wear and vibrations because the radius is smaller so the chain warps more around it. Have you any advices on this topic? Why would I want more power from such a light machine, well I like riding steep uphill hilly roads and quite often I just have to shift down and I have a feeling it would be much more smoother ride if the gears were set up more on the torque side. Top speed is not my priority.
Good luck, thanx.
Excellent video. Thanks!
no worries mate - matt
Absolutelly fantastic explanation! Been looking for this on UA-cam for a long time! Do you know if Harley's gearbox uses the same system?
Wow, this is the best explanation I've seen so far (and I've watched a number of these), but I still have some questions. To start though, I'll put down what I came away with.
On a 5 speed,
1) There are 5 gears on the input shaft and 5 gears on the output shaft
2) All gears on one shaft are constantly messing with gears on the opposite shaft
3) Fixed gears always mess with freewheeling gears on the other shaft
4) 1st, 2nd, and 3rd gears (1st, 3rd, and 5th gear measured from center of bike) on the input shaft are fixed and 4th, and 5th gears ( 2nd and 4th from inside) are freewheeling
5) Therefore, on the output shaft, gears 1, 3, and 5 are freewheeling and gears 2 and 4 are fixed
6) The dog gears are always on the side of fixed gears
Right so far?
I can tell from reading the comments on all these videos that everybody is fascinated with how you can shift without using the clutch. So what happens when you pull in the clutch. It disengages the driveshaft from the input shaft and the input shaft should start slowing down to a stop. Right?
Questions: How fast does this happen? Is it in a second or two or much longer? Does what gear you are in effect the speed of slow down? Why would it stop spinning at all except if in neutral? Wouldn't the output shaft keep it moving (assuming the bike is in motion)?
To continue, the input shaft has now slowed to a stop, causing the freewheeling gears on the output shaft to also slow to a stop. However, the output shaft is turning with wheel rotation speed, so all the gears fixed to the output shaft will still be spinning? Right so far?
So when a shift is made, the rotating dogs are going to clash with cavities in side of the slower moving freewheeling gears. This is why the tops of the dogs in your video were ground down somewhat.
So, I'm not sure how clutching even helps. (?)
If you DON'T clutch, the input shaft is still spinning, as is the output shaft. Again when you shift, you are going to have a clash between dogs and dog cavities. In fact, because both shafts are spinning, it seems as if the shift would be smoother. (?)
I feel like I am almost understanding this, but not quite.
Hello mate, this is going to be a long one lol
"So what happens when you pull in the clutch. It disengages the
driveshaft from the input shaft and the input shaft should start slowing
down to a stop. Right?"
No. - the clutch disengages the clutch basket from the clutch boss which is attached to the inputshaft if we're being technical. Here this might help -
ua-cam.com/video/d74A37h4v6c/v-deo.html
Seondly the inputshaft slows down yes but not very much as the you change gear and then engage the clutch again. The clutch is used to disconnect the inputshaft from any torque thats applied to it. When the next selected gear is engaged the shaft has no resistance to this change, and it would if the engine was apply a torque to it.
"Questions: How fast does this happen? Is it in a second or two or much
longer? Does what gear you are in effect the speed of slow down? Why
would it stop spinning at all except if in neutral? Wouldn't the output
shaft keep it moving (assuming the bike is in motion)?"
Yes - I kinda answered this one above.
"To continue, the input shaft has now slowed to a stop, causing the
freewheeling gears on the output shaft to also slow to a stop. However,
the output shaft is turning with wheel rotation speed, so all the gears
fixed to the output shaft will still be spinning? Right so far?"
Again the inputshaft doesn't stop.
"So when a shift is made, the rotating dogs are going to clash with
cavities in side of the slower moving freewheeling gears. This is why
the tops of the dogs in your video were ground down somewhat."
- correct, the dogs are the feature of a gear that experiences the most wear. These gearboxes aere called constant mesh, if you hear grinding then its the dogs chattering not the teeth of the gears.
"So, I'm not sure how clutching even helps. (?)"
I stated above that the clutch is used to disengage the shaft from the torque that is applied to it.
"If you DON'T clutch, the input shaft is still spinning, as is the output
shaft. Again when you shift, you are going to have a clash between
dogs and dog cavities. In fact, because both shafts are spinning, it
seems as if the shift would be smoother. (?) "
Good question - you half of it right. Both shaft will continue to rotate as you engage the clutch, but they will deaccelerate. The input shaft will 'freewheel' as an entire assembely. The output shaft on the other hand will reduce speed due to the friction between the road and the tyre which the output shaft is connected to. This is turn is connected to the input shaft as they are constant mesh. So the gearbox reduces speed at the same rate the rear wheel (which is no unpowered) will. If you think of it like this. If you pull your clutch in the bike will roll to a stop no matter what gear your in.
Anyroad, when you select another gear and release the clutch you continue on your way. Basically your disconnecting the power from both shafts this means there is less resistance when you mesh dogs together. The 'impact' between the meshing dogs is alot lower.
Clutchless shift means that the impact is much greater, this reduces the life of the gears.
Another way to think about it (very loose analogy) is changing gears on a push bike. If you are climbing a hill and change gear and putting your back into you hear a horrible clunking and you can feel the change is rough.
Hope this helps - if not I'll do a video on making gear change and clutchless shifting
Thanks for that response!
I understand about the clutch, etc. So when the clutch is pressed in, the input shaft keeps rotating but without the torque it has when not engaged? It is then the case that the input shaft's resistance to matching the output shaft is just the inertia in the shaft itself and not the inertia due to the pistons, etc.? It's the resistance to the "shock" of the dogs engaging that is important and not so much the speed differential between the dos and dog recesses? Is that right?
I just had a bit of an insight. Damage to the dogs and recesses can be done not just by normal grinding on the end of the dog, but also by the shock when the dog hits the end of the recess. This shock can be minimized in two ways. 1) By using the clutch to disengage the input shaft from the engine, thus reducing the resistance to turning of the gear with the recesses or 2) By matching the speed of the freewheeling gear to that of the fixed gear with the dogs. Shifting without clutching involves this latter method. If you were perfect at matching the speed there would be even less shock than when the clutch is used.
Is that right?
lol yes mate, the problem with clutchless shift is that we're human, and can't perfectly match the speed of the two shafts. You got to remember that the speed of the shaft is the macth speed of the gear you WERE in not the speed of the shaft you want to be in when the engage the next gear. Think of torque as energy. When you disengage the clutch the energy tranfers form the engine into the input shaft diappears. Its motion is now 'powered' by the inertia stored in the shaft. When you select the next gear the impact (energy transfer) between the dogs and the recesses comes from the inertia in the shaft. If the engine was connected to the shaft when the shift takes place the torque (energy form the engine) is transfered into the dog recess throught the dogs on the moving gear. This results in higher impact energies cause more stress on the gear moving and the gear being selected.
This is why gears are hardened, they behave like the impact anvils in a impact gun. If you can do something (use your clutch instead of clutchless shifting) this will prolong the life of your gear box.
Pony Power I think I've got it! In theory (although not in practice), someone could match the dog gear with the dog recess let the dog pop in and then minutely increase the speed of the dog gear so that it would just softly press against the front of the dog recess resulting in the perfect shift!
Very good video! Thanks a lot!!!
No worries mate, thanks for watching - matt
you would have triple the viewer if it counted each view individual per person . im going to need to rewatch this about 100 times ! thanks for the info mate cant wait to see your finished kawasaki
+hoggath hogg thanks for the comment dude. Yeah the kawasaki is coming along (slowly that is) I've seen alot of the gerabox videos on youtube and they don't quite go into what actual goes on inside. There will be some more videos related to this series, car gearboxes etc - cheers for the comment - matt
thanks for sharing the knowledge mate really helps !
No worries thanks for the gracious comment
More gearbox videos please!
Outstanding explanation, thank you for sharing. I'm gathering as much information that I can before diving into a ktm 525 gear case that has a problem with going into reverse. I'm working on a 2008 polaris outlaw 525 (atv). Your video helps to build my confidence. Any advice on my situation would be greatly appreciated. Thanks again!
Thanks for your comment, much appreciated. Give me more information and I'll see if I can help. Is your problem physically engaging reverse or problems whilst in reverse i.e keeps slipping out of gear? thanks again - matt
The only information I have is that from the previous owner. The atv was in reverse and high centered on a rock when he hurt a loud clunk and the engine stopped running. The atv performs normally in all forward gears, it's only when you shift in reverse the engine stops after moving less than a foot. The atv is difficult to get back into first gear but once there it begins operating as normal. I'm currently in the process of taking the engine apart to see if I can find anything that's obviously broke. I'm having to wait for a few special tools to arrive before I'm able to get inside the engine. Thank you for the reply.
Well-explained. Thanks.
+TroyaE117 thanks for the comment dude - matt
Dear all, does anybody knows why some motorcycle gearboxes have the following gear order, starting from the clutch: 1-5-3-4-6-2, and others: 1-5-4-3-6-2? Which is the reason to change the 3rd and the 4th gears position?
very good broother
Hello Matt. i really like your videos about gearbox, overdrive and sprockets. learned a lot from them. i have a small question.
these specs are from a CBR manual.
primary reduction ratio: 2.117
1st gear ratio: 3.307
final reduction ratio: 2.600
so let's just say we are in 1st gear and we need to find how many times crank rotates for one revolution of rear wheel.
can we find it by final reduction ratio*1st gear ratio* primary reduction ratio ?
so in that CBR bike it's, 2.600*3.307*2.117 = 18.2
is it right ? thx a lot. keep it up 😊
No. The first ratio is a reduction. I.e a drop in speed, increase in torque. Do you usually convert the rpm and primary to just an input.
So you take say 10,000 rpm and / 2.117 to get 4,724. This is your input.
@@dirtygarageguy thank you 😊
When you're at rest and going from neutral to first, and both shafts are stationary, if the dogs are not aligned with the slots, how do you shift?
That's a video coming this week
Would you know why the gear box on my 03 bmw f650 gs suddenly wont go into first what could be wrong
Okay, so do we need to clutch when changing gears for the sake of longevity?
@Njato Andrianarison
Definitely YES, you need to clutch to reduce wear and tear on the dogs. Pulling in the clutch disconnects the engine from the gearbox's input shaft. This will reduce the input shaft's rpm which in turn reduces the pressure/friction on the dog teeth when they disengage from one gear (say 1st gear), and it also reduces the slamming force on the dog teeth as they slide into the next gear (2nd gear).
You can certainly change gears without clutching by closing the throttle just before you shift. This method will also reduce the gearbox input shaft's rpm, but not as much and as quickly as pulling in the clutch, which means you have a little less wear-tear protection of the dogs compared to the clutching method.
Excellent vid
very good video, cheers!
No worries mate thanks for commenting - matt
I have a Malaguti dune 75 ks with a AM6 engine and i have a problem ,i can't change into third gear it only goes in first,neutral easy with no click and sometime in second gear and sometimes it drops from second into neutral,what could be the problem
Great explanation, thanks!
No worries mate thanks for the comment
A mini Matt in my toolbox would be good
Brilliant video thank u 👀♥️👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍
Whats your opinion on clutchless shifting. Does it ruin the dog teeth or damage the transmission in any other way.
Downshifting is more damaging than upshifting generally. Your clutch is used to reduce the speed and torque when switching between gears, if you don't use your clutch and change gear at the same rpm as you normally would this increases the amount of impact between the dogs and their respective holes. In general this reduces the lift* (I mean life) of the gear set.
Pony Power What makes downshifting more damaging than up-shifting. Also what did you mean by "reduces lift"?
Awesome video btw.
Aashwin Varshney when you downshift you increase the load on the engine, this is called engine braking. As for why downshift, simply because your over-ranging the gears (if that's a word) i.e your subjecting that selected gear set to speeds/torque from a very low load and speed. Its like jumping off a bus and trying to run to maintain 30mph. As for lift I meant to say life lol - thanks for the comment - matt
Hello, please can i ask you which motorcycle is it and how it´s the axial distance between the shafts? I´ll be grateful if you will help me with it.
the engine is from a 1998 Kawasaki KX250 2 stroke.
- "how it´s the axial distance between the shafts?" not sure what this means? If you asking what is the distance between the input and output shaft - I don't know off the top of my head, and I don't understand why you would want to know???
Thank´s a lot :) Yes i mean that dimension between input and output shafts.I need that dimension for my diploma work.
Ondrej Novak
The dimension can be anything you want, but if you want me to just give you a number, ok - 68mm center to center
ok thank you for your time :)
Osm video bro its clear all my doubt yrrr
sir my bajaj discover 125cc the gear is jumping from 3 st to 1st gear it is missing 2nd gear for this problem any solution please give a repair vedio
thanks dude you helped alot
My ktm duke 125 keeps jumping from 2nd to neutral, 4th to neutral and maybe 2nd to 1st...its quite scary sometimes, should i replace the whole transmission or leave it to a mechanic?
+Dakota Rising You probably won't have to replace the whole transmission, if you look at this video ua-cam.com/video/UjaNXrcU3BA/v-deo.html at 9:20 onwards you should have a good idea whats going on it probably one of your springs has given up the ghost so to speak hope this helps if not just ask - matt
Thanks mate, i'll watch this when I get home..cheers
No worries
Thanks for the education. Very good (c8
No worries mate, thanks for the comment - I'll be doing a follow up video with a cut away gearbox I'm in the process of doing - matt
Does the car's sequential dogbox work the same
Yes - well they are very similar.
best i've seen!
Thanks for the comment mate - matt
next, ''spooky quantum physics'' which is much easier to comprehend.
Hey mate can u tell me the Torque & speed of the engine which uses this type of gear box?
Also let me know the speed at the clutch side.
Hello mate, I'm abit unsure what you mean? The torque and speed are changing depending and how much you rev the engine. If you can be more specific then I can help - matt
Pony Power Tell me the power of engine at a particular speed
42Hp @ 9,000rpm
or 31 kW @ 9,000 rpm
Thanks mate
matt.. you look so young in this video... what went wrong? or where the years cruel to you? :D
Cocaine mate, bad trip
I have a 2009 Triumph SE. Recently, I have serious problem to shift to neutral. When i stop for traffic light and in first gear, try to shift to neutral, I always shift to second gear no matter how careful I shift. Then I try to shift from second to neutral, it become so hard to press the gear shifter down, so I jammed in second gear..... If I successfully shift down , 90% I shift to first. Neutral just become so hard to engage. Why this happened? I own the motor for over 7 years, and I never had any problem to shift to neutral till recently. I don't have any problem to shift to any gear when bike is moving. Anyone know what went wrong? Any parts I may need to replace?
Hello mate - right so I've had this problem in the past only not with a Triumph.
Simple things first
1) It can be your clutch cable. Usually the culprit (9/10 times) Over time the clutch cable will stretch, this causes the clutch to not disengage fully. Which means your input shaft has torque applied to it. This will cause your gearbox to 'ride over' the neutral detent. Firstly adjust your cable tension, if that sorts your problem you can run with thta or buy a new one its up to you.
2) Your using the wrong oil. Triumphs are easily pissed off with lower quality oils. Again this is a clutch problem. Cheap olis usually don't conatin sexy friction modifiers which help your clutch slip when. The oil misbehalfs when it get to higher temperatures. Use recommended oil that Triumph specify.
3) This is less likely but depends of the milage of your machine. Your steel plates are beginning to warp - again a clutch problem. This can cause your clutch to stick together and yet again not seperate properly.
In summary its a clutch problem, not without a doubt but 99%. Try set 1 first and go from there. Adjusting your clutch cable should give you some result. I.e better or worse.
Message me back if you have any problems or a success
Hope this helps - matt
hi thre i have a question about enduro transmission
go on then, what's the question?
What's the difference on an enduro transmission
For people who don't know BMW offer an endurance transmission when you purchase a GS, usually at no extra cost.
The difference is the gear ratio for 1st gear. The rest (as I understand it, unless the new model is different) are the same. The whole point it is to give the the ability to poddle around in 1st gear without reving the crap out of the engine. Basically you can pull away in first without using the throttle. This can help if the rear wheel slips when off road. This is an option with the big cc BMWs mainly due to their weight.
With a different ratio for 1st, more speed is converted into torque. This allows the bike to 'push' the heavier bike at low revs. This is not needed for off-road bikes because;
1. they're lighter so less torque is required to move the lighter mass
2. they already have a gearbox ratio set-up for off-roading
The GS is a road bike which also has the ability to do abit of off-roading. If you buy the bike to do mostly off-roading they will switch out the 1st gear set for the 'enduro' set. They reason why it doesn't cost anything is because they're just switching out one gear pair. 1 less tooth on the input gear and an extra tooth on the output shaft.
Hope that helps
Matt
thank you now I understand
do you have any videos or know of and with reversed gearing, as in down shift to higher gears and up shift to lower gears
no mate I don't - can you be more specific?
Say, normally, the shift patern is 1 down 5 up, im wanting to put my shift patern where its 1 up and 5 down, or all 6 down
ok, why comes to mind, and secondly its possible but with some major modifications.
+Pony Power yes my cbr f4i motors starting to get to the really in need of a rebuild poing and the transmissions all grindy in nuetral at idle speed, i put a new clutch in her but its still clackity, i was thinking it be something to do while rebuilding
ah right, any bike can have the selector changed to say 6 down for example but it means changing the selector drum. This isn't something you can just do and they don't sell them as aftermarket parts. If your gearbox is grinding in neutral then you have a selector issue. In a working gearbox the when in neutral everything should be free-wheeling. Are you sure its coming from the gearbox?
Hello bro how are you? Sir please tell me how to buy automatic gairbox
How to buy one?
I'm still trying to understand why you don't need to use a clutch to shift. Are the dogs on the dog gears on one shaft all aligned?
Never mind, I can see they are not.
I still can't understand why a clutchless shift is smoother than one using the clutch.
Don't worry mate a video is coming up - matt
ua-cam.com/video/NxlNjfYep_w/v-deo.html
Excellent! I've watched most of the videos on motorcycle transmissions and read lots of the comments and there's a repeating conversation that goes like this:
Commenter 1 - If you can shift without a clutch then why even have one? What are you giving up?
Commenter 2 - It will harm your gears if you don't do it right.
Commenter 3 - I've been doing it for years with no harm and besides it is easy to do right.
Commenter 4 - You only need the clutch for starting in first gear. Old buses and lorries (trucks) used to only have a clutch for starting.
Commenter 5 - I use the clutch on the 1-2 shift because neutral is between them and that makes it harder.
Commenter 6 - I don't use it for downshifting. You can jerk the bike if you do that.
Commenter 7 - I do it even downshifting.
No where is part one of the original question answered. I hope your video does that.
My best guess now is that it involves speed matching -- not of the adjacent gears necessarily but of the rotation of the input and output shaft, or maybe that amounts to the same thing.
9:05 Are the "dog recesses" the reason why bikers can perform clutchless gear changes?
+cRizy89 I don't know what your asking, but I think I know what you mean. Dogs are fitted to both car and bike transmissions, cars tend to have synchro rings which is abit more complicated but the idea is the same. Gear teeth are precision cut features, people think that the gears engage each other and change location when a shift is performed. This would quickly wreck the gear surface and make shifting impossible. Dogs are more robust due to their simplicity. Changing gear using the clutch or without doesn't effect the way in which gear are selected. And another point which I get asked alot, clutchless shifting damages your gearbox.
+Pony Power Ohhh I see. Then why is clutchless shifting more acceptable to be performed on bikes then it's in cars? I saw a video in which it stated that due to having a sequential gearbox, clutchless shifting is possible (or a natural/normal thing). That's why I started watching your videos trying to find an answer as to why this is acceptable thing, by a large amount of people, for these types of gearboxes. By the way, on my original comment, I meant the wider dog recesses, rather than being a dog recesses just big enough for the dogs, without any further room (I did understand your answer though).
its ok.nice
still i can't understand how a gear box works. can u explain it in more detail.
You'll have to explain which part or what you don't understand before I can make it any clearer - matt
i can't understand how gear works......and how gear shifts from one to two ,two to three, like that
Here's a video for you dude - matt ua-cam.com/video/DhpxuQC7VjE/v-deo.html
thank u for this AV matttt.......now i understood clearly how a gear mechanism works
Can you explain why old YZ250 gearboxes keep wrecking 3rd and 5th gear
And RM250 gearboxes keep wrecking 2nd and 3rd gear 🙄
When you say wrecking, what do you mean?
The Workshop raced a 2005 YZ250 last year and had to replace 3rd and 5th twice plus a selector fork
It was the dogs kept wearing away within the space of a few months
And the RM liked to round of 2nd gear
Using your clutch?
The Workshop used to only use it going down but now ive started using it all the time 🙈
great explain,but I hope you can ware rubber gloves,other wise will be hurt hand and fingers
Why all the gears? Why not have a motorcycle in 5th or 6th gear at all times?
LOL what?
I love her but she always blames me
My 2022 mt09’s gearbox whines like a fucking drag car 6th gear is the worst!!
Will the whole mechanism still work if the input shaft is rotating at the opposite direction ?
Actually, I'm making a project and going to install the gearbox to a motor rotating the shaft. What I want to ask is whether the mechanism will act as reverse when I change motor's polarity. Or will it not work at all?
Will the whole mechanism still work if the input shaft is rotating at the opposite direction ?
Actually, I'm making a project and going to install the gearbox to a motor rotating the shaft. What I want to ask is whether the mechanism will act as reverse when I change motor's polarity. Or will it not work at all?
+Ankur Ralhan sorry for the late reply, google marked your comment as spam for some reason? Anyroad, yeah the mechanism work in both directions apart from the selector drum. So changing gears has to be the same way. Good gearboxes if your wanting to use them for a lathe or milling machine, can easily take the torque. Hope this helps - matt