How a Motorcycle Gearbox works - Part 2

[@wongchow]

I looked around for a really thorough explanation. This was the best.

[@thedirtyworkshop]

Thanks for the comment dude - matt

[@vijayam1]

Matt, appreciate the effort you've put in for both videos, very very VERY helpful.

[@thedirtyworkshop]

Vijay Anand No worries mate that's what they're for and Im happy they helped you, thanks for the comment

[@witchking2124]

The best videos this one and the first part ,the best i ever seen about gear box,clutch with great explanations,thank you very much

[@thedirtyworkshop]

No worries mate thanks for the comments - matt

[@brentsmith5647]

Brilliant man 👀♥️👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍

[@albertoruiz1008]

thanks a lot for the info I'm going to check that out I really appreciate your videos thanks

[@thedirtyworkshop]

no worries mate thanks for the comment

[@DaHitch]

Hey, I have a question you might be able to answer for me. On modern motorcycles there's often a gear selection indicator on the dashboard, how does the onboard computer know what gear its in? Does it just count a number of clicks on the pedal/selector drum or does it detect the movement of the selection forks?

[@thedirtyworkshop]

Some have halls effect sensors on the selector drum and other systems use contact strips along the circumference of the selector drum and use a resistance reading. Hope this helps - matt

[@robinhood8119]

Thank you

[@RS-lm1cz]

Hello Matt. have a small question. at 10:50 you mention that the selector drum is cast iron. i have seen some bushings are made out of cast iron and bronze. what quality makes manufacturers select them for those specific places ? does that mean cast iron wears a lot slower and it also has a minimum impact on the material which is rubbing against it ( steel shift forks in your example ). thank you and keep it up 😊

[@thedirtyworkshop]

Not all are, but it has been a common material of choice. Cast iron has granulated sections of carbon that hasn't dissolved properly. These act as integrated dry lubricant as the part wears.

[@RS-lm1cz]

@@thedirtyworkshop thx a lot Matt 😊

[@brentsmith5647]

Brilliant video thank u 👀♥️👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍👍

[@robinhood8119]

I opened my engine and in the inputshaft were 4 i don't know how to call them , two are small,one is medium size and one is long and they came out from the hole of the inputshaft and i don't know what are they for and the order to put them back inside,can you tell me please ? if you know what i am talking about,sorry my english.

[@thedirtyworkshop]

robin hood can you send me a picture, do you have facebook?

[@robinhood8119]

Pony Power no i don't have a facebook account and pictures but now i remember that they dropped when i took off the clutch basket, was first something like a nail and a small ball like a bearing ball and then dropped the rest, the 4 things that look like nails but without ends and now i'm afraid to put them back in a random order,idk if there are important or not,there are all of them in the shaft.

[@thedirtyworkshop]

The small bball bearing is for your push rod to engage/disengage the clutch. as for the other bits i need to look at the gearbox layout, what ATV do you have and I can hep you from there.

[@robinhood8119]

Pony Power It's a dirt bike with an Minareli am6 engine with 6 gears,and yes the bball bearing is from the clutch,and i'm sure that the other 4 bits are from inside the input shaft and idk what are for and the order like i said and i can't find on internet,damn. I think i will put them in random order and hope that nothing wrong will happen.Thank you very much,you made awesome videos with very very good explanations,i never saw good videos like these.

[@thedirtyworkshop]

robin hood I think I know what your onj about now, do you have a spring aswel. The ball bearing isn't from the clutch its from the selector drum and the 'needles' are also from the selector drum. Check the google for images of the transmission or find a how to reassemble the AM6. The bike has been be in second gear when you assemble it. The ball and spring are a detent follower. - hope this helps

[@hulk2891]

im going to attemped to change 2nd and 5th on on bike im going to buy, fjr 1300 as told by garage they where worn,it would make sense that 2 and 5 or worn on fjr as they run together would that make sense?any ideal if i will have to drop the engine out?cheers..glad i came across your vid:)

[@thedirtyworkshop]

+hulk hoggan lol FJR's that's a whole kettle of fish on its own. They have an electric clutch and a prop shaft. They also have neutral at the bottom of the gear selection. No down 1 up 4 lark. Gears 2 and 5 are on the output side of the prop shaft so yeah that makes sense (towards the back of the bike) This garage that told you they were worn, what do they mean? And how do they know? Did they strip the box and look but not fix? Also, yes my frind you'll have to remove the engine from the bike. The case is split horizontally and the whole bottom of the casing has to be removed. Trying to do it with the engine in the bike would be like fighting a midget whilst standing on your head. Hope this helps - any more questions just fire away - matt

[@hulk2891]

+Pony Power seems then had a keyhole camera ,ill get back to you with the symptoms.cheers for info

[@thedirtyworkshop]

No worries mate. Just seems abit weird, they probably mean the dogs on the gears not the gear teeth themselves. - matt

[@hulk2891]

yeah but still need replace 2 and 5 yes ?

[@thedirtyworkshop]

+hulk hoggan yes mate you will have to replace them. If the dogs are knackered then you'll have to check 3rd gear as well. If the gear teeth themselves are knackered then you'll have to replace the other mating gears to.

[@7878biscuit]

I am rebuilding the same engine at the moment and the shifter forks came out I am wondering what postion the drum should be in when you reinstall it? Great video very helpful

[@thedirtyworkshop]

Cheers for the comment- I've been having problems replying to comments but I've fixed it now - did you get it sorted - sorry for the massive delay - thanks again matt

[@austinluck3805]

Hello very helpful video i was working on rebuilding an engine and i rotated the selector one click because i thought it was necessary for neutral selection. however after the rebuild bike runs great lots of power every gear works fine except 5th gearit acts like neutral and the gears did not burn out on me! So my question is do you think its possible the my misaligned selector would allow for perfect shifting except 5th gear or is their another culprit thanks in advance.

[@thedirtyworkshop]

what engine is this and the quick answer is no. The selector drum has a hard stop.

[@austinluck3805]

this is a ttr 125cc 4 stroke and what is wierd is that it worked before and i never moved any components in the gearbox besides the rotation of that selector shaft

[@brenguy333]

What do you use to mark the internal engine parts with? Like say I wanted to make markings to ensure everything stays in sync when i re-assemble an engine? Is white out fine?

[@thedirtyworkshop]

I use a paint pen

[@mattkemp1902]

Brendan Posca is a good brand. I use it to mark links on my chain for cleaning or measuring slack. Comes off easy when you want to but hangs about long enough to be useful

[@reco900rr]

What is that paint pen called?? I use the texpen and hate it. Thanks

[@thedirtyworkshop]

Its called a Posca Paint Marker and its great, just have to make sure you clean the tip now and then with solvent.

[@rickmurphy123]

how about 2000 suauki marauder 800 cc transmission can you show it thank you for time.

[@thedirtyworkshop]

Sorry mate but I don't have an endless supply of gearboxes. What seems to be your problem with your box? Most gearboxes are pretty much the same, slight differences but not much different than the one shown above. Thanks for the comment - matt

[@hulk2891]

matt hi ,update on fjr, it would appear the bike slips abit under hard acceleration it was explained like the rear end hunches downI mean hard on the throttle 7\8k rpm. Normal riding conditions its fine. I've seen posts on forums saying these are common faults and people riding normal theres no reason to panic and straight to garage .the problem is there but till its broken don't fix it so just easy on throttle and may or may not last 1k 2k or 10k..I thank you in advance for you help and inforegards keith

[@thedirtyworkshop]

+hulk hoggan Not familier enough with the FJR, sounds like a clutch problem and due to it being electronic, that could be the issue. As for the hunching down, shaft drive bikes do this but at low rpm high torque as the shaft tries to climb up the ring rear. Hope you sort it - thanks for the comments - matt

[@albertoruiz1008]

why do you think my 2003 sportster goes into nutrall when I go into 4th gear can't figure it out

[@thedirtyworkshop]

it goes straight from 4th into neutral? Its a 6 speed right?

[@albertoruiz1008]

No its not a 6 speed it's a 5 speed, when I go from 3 to 4th it goes into nutrall then it goes into 5th when I shift it

[@thedirtyworkshop]

It can't be going into neutral as that's too far away, you're getting stuck between gear changes. It's probably to do with your selector cam. One of the springs is probably broken

[@witchking2124]

Please give me an answer at what i asked you in the first part please

[@dustyhusqy5403]

I am sure you know your stuff very well but you are a bit to chaotic explaining it