AM6 Gearbox Assembly - step by step

AM6 Gearbox Assembly - step by step
An easy to follow guide, showing how to assemble the AM6 gearbox.
This tutorial applies to the following motorcycles:
MX50, RX50, RS50, Aprilia, Yamaha, TZR 50, DT 50, Rieju, Peugeot XR6, Malaguti Drakon 50, Derbi.
Similar assembly techniques and tips can be used on various two stroke (2T) engines.
Take note of the shims, and the location of the shims in the gearbox.
If possible, obtain the workshop manual.
This will provide various technical specifications, and measurements, that will help during the gearbox and engine assembly.
Website:
fuelmapper.com/

[@marcinkozowski5017]

This video is an absolute lifesaver to all those doing work on an AM6 engine for the first time. Hands down the best tutorial about AM6 gearbox assembly/disassembly. Very clear and informative. Thank you very much sir!

[@EngineTuning]

Thanks for those kind words Marcin :)

[@virgiswolf5499]

I definatly agree. Good videos man.

[@Kukkovi]

Ty! helped me rebuild my peugeot xp street evo 3 gearbox. I couldn't find any other videos that show the places of the shims. 🙏

[@aleksikortesalmi]

I havent watched any more helpful video in my life. Big thanks

[@EngineTuning]

Thank you for that positive feedback. Good luck with your project :)

[@alexander23471]

Absolutely the best video about the AM6 gearbox.

[@EngineTuning]

Thanks Alexander; pleased it got you through the task :)

[@jordanb2769]

thank you for the explaination of testing the different gear ie gear 1 neutal etc it help alot :D

[@EngineTuning]

+Jordan Berry Thanks for that feedback Jordan..... I'm glad that I remembered to include it :)

[@SB-Smile]

This video is pure gold

[@mrksk2132]

You really help me man :D thanks and greetings

[@markjenkins7757]

You have been a really big help❤

[@EngineTuning]

Thanks for those kind words Mark :)

[@jarkkooppilas7611]

Great video!

[@EngineTuning]

Thanks Jarkko... kind words indeed :)

[@simonvickerman9598]

Reall good video really helped me and my son rebuild gear box still got a knocking on engine only play was balance shaft that we found could this be worn

[@EngineTuning]

Thanks Simon.... it's good to hear that the video helped. Regarding the knocking.... you really need to set yourself up, to ask this question, or any question involving noise. (in fact for any technical question). Ideally, I need to know when the knocking occurs. Is it when revving out of gear..... accelerating, decelerating, or at feathered throttle? For noise.... uploading a video is usual.... with the exact moment the noise starts, being marked on the video. That's because sometimes the noise isn't clear until it is indicated. For your own audio testing.... Pure rotational components don't usually knock under engine acceleration.... everything is pushing together so there is no space to knock. They are more likely to whine or grind, particularly under load, if a bearing has failed. Nuts can come loose if properly fixed.... heard of tapping case two weeks ago that was sourced to a loose nut. However.... most knocking is related to the crank and piston region. As the crank pushes the assembly up..... at top dead centre, the assembly wants to keep going up (Newton again). If there is any play, it moves through that space, then metal hits metal, and clanks! Same going down. Little end knocks tend to be higher pitched than big end knocks. Using a screw-driver as a probe, with your ear on the end of the handle, can help identify the knock region. Good luck :)

[@makee6321]

Thanks man !!!

[@tramppasamppa223]

i tooked the ball bearing off from the spring and now the drum is working almost perfectly without the ball bearing.. is it okay if i dont put the ball bearing? if i have to put the ballbearing what should i do to get it work..

[@RealfishingNL]

awesome thank you🖒🖒🖒🖒🖒🖒🖒

[@robinhood8119]

Thank you very much,i have the same engine but with 6 gears,and the bottom of my gear shift cam is different ,it looks like a star and there is a spring without the ball bearing and this is why i have problems shifting gears i think because of that spring if i tight it to much i can't shift at all and if i let it lose i shift to easy without ''clicks'' and i think if i let it like this it will drop from gears,i split the engine because it wouldn't shift in third gear and i thought that the shift forks are bent but nothing was bent,can you tell me please for what is that spring and how to resolve the problem and another thing when i split the cases from the output shaft dropped 4 things idk how to call them,look like nails without the ends and 2 are the same size 1 cm long,one is 3 cm and one has 5 cm and they dropped from the hole of the output shaft and now idk what is the order to put them inside,i hope you can help me with this,is very important for me and maybe there are other with this problems.

[@tuitsu]

Thank you man!

[@EngineTuning]

Cool ... a new video is about to be uploaded ... No. 7 in the AM6 rebuild series. Check the playlist: kzbin.info/door/YZDGH1LaEcDf3zdVJMbQhwplaylists I've got material to the 'complete bottom end'. I've designed a porting tool kit, and am awaiting the components ... to show how you can use it, to improve your top end. So, until then, the new rebuild series is being edited and uploaded. Subscribe, and click on the bell (that appears) - choose to be notified of the next vid in the series. If you just subscribe ... it's like a big 'thumbs up' (which is fine). ... but if you actually want the knowledge, then you need to hit the 'bell icon', Good luck with your project, and thanks for taking the time to comment :)

[@calvinvanalloveryawesomene680]

very understandable explanation.

[@EngineTuning]

Thanks for the feedback Calvin :)

[@tramppasamppa223]

i have 2006 cpi sx 50 supercross and i found many videos where they but the gear drums stick to another position than u did. wich one is right way? plz help i want to go riding :DD but very good videos dude helped a lot! :)

[@EngineTuning]

My way of course :) It is fiddly..... but you don't need to force anything in....... and the gears should rotate freely.!! Get yourself comfortable, with a good light source. Take it steadily, and stay in control of the assembly. When you put the 2nd case on...... test turn the motor. when you first tighten the bolts...... test turn the motor. When you've finished tightening the bolts..... test turn the motor. Good Luck!

[@MarcooMRT]

Hey great video! i have a question, here in denmark the gear shift cam is restricted in the new engines so we only have 4 gears, if i was to change this back to an normal one, i would be able to shift into all 6 gears by turning the gear shift cam before assembling it again right? so i dont have to assembly it all just to find i still only have 4 gears or something.

[@EngineTuning]

I have never heard of this restrictive mod. In fact; it doesn't make sense to me. The objective of the gearbox is to enable acceleration, by matching load to rpm. ... One cannot simply eliminate 2 of the gears, without matching the remaining 4 gears to the load and rpm. If this is happening, then... in 4th gear, the engine will be revving it's guts out. That is, unless the gearbox has been completely redesigned to spread the load across 4 gears (instead of 6).

[@protrader9129]

very good. thanks

[@EngineTuning]

Glad that it helped :)

[@ginteew]

Building a new engine for my yamaha and this is a really big help !! thank you good sir

[@EngineTuning]

Thanks for the feedback... it makes it all worthwhile :)

[@davorkosec6674]

Great videos . I need information . I have 1998. Rx 50 Aprilia . If I am going to put inside Polini 70 ccm , 47 bore kit , do I have to make any change in crancases? Do I need to grind the crankshaft blocks to get the cylinder well inside and the piston not to hit the bottom dead center in the blocks? It is rare old Polini W shape kit. Tnx

[@EngineTuning]

For a 70cc BBK, I haven't heard of one requiring engineering mods, because 70cc can be gained from the available space. Good luck with your project ... it sounds great :)

[@egarazcz]

hi, i'm changing bearings on crankshaft and my racing crankshaft kitt is containing two bearings - one with side cover ( plastic cover inside bearing ). Which way should be bearing ( covered side ) pointing to ? thanks

[@EngineTuning]

+egarazcz Non-standard kit 'installation instructions', should be supplied by the manufacturer. In principal.... Make sure that the exposed side, is open to lubrication, and covered side to the outside. Bearing covers can be used to keep dirt out of the bearings, however, this is less relevant here. The stock bearings have the same part number, so both are the same.

[@tiemensikma5938]

thank you so much for this video it helped a lot. I do have on question i hope you could help me with: when I tighten all the bolts on de two engine halves my primairy and secundairu shaft are both stuck but my crankshaft wil turn, when I loosen the bolts slightly they will turn but with great resistance (it shifts fine though). Do you know what causes the resistance?

[@EngineTuning]

It's possible that you have the shims in the wrong place. Dismantle ... remove everything... test assembly with one shaft, then the other, then both together. This way, you will discover exactly where the problem is

[@tiemensikma5938]

PlayF1 Net yess will do thank you

[@motomadness2908]

Hello i have question i put Zall together and my camshaft move right to left

[@EngineTuning]

Hi Moto :) When asking a question ... Take your time ! Consider first typing it in Notepad++ When you have included all the relevant info, and checked the spelling & terminology ... you can simply copy and paste it. EG. 'camshaft' ? There is no camshaft in a 2 stroke. Do you mean 'shift-cam'? Or maybe 'crankshaft'?

[@XXxfreddex]

please i need help, how much play should there be on the sprocket shaft? i think i may have a bit to much

[@EngineTuning]

Check out this video: kzbin.info/www/bejne/ep_Ncoefp7VsmsU I presume that you mean the play between the front sprocket splines and the splines on the output shaft. If this is the case, it would be fairly typical. As you open the throttle, all the power is passed through those splines. The splines slam into the sprocket splines, and get the whole bike and maybe two people, moving. This tends to wear out the splines, so the play gets greater. With more play, the shock of the load on the splines is greater. This creates even more play, which in turn further increases the shock on the splines. It is an accelerating failure. The only way to solve it, is a complete engine and gearbox split, replacing the worn shaft and worn sprocket. From that point, you can regularly replace the sprocket, extending the life of the shaft. The cost of the shaft is anything from €15 to €75.... so look around. The cost of the sprocket is just a few euros. Good luck!

[@162BeatsTrapBeats]

I changed my cylinder from a 80cc Top Performance (the pink one) to a DR50 cylinder, ever since my first gear is rattling really loud. You feel it vibrating the bike (Yamaha TZR50). I don't really have an explanation for it yet, I'm going to take apart my clutch tomorrow to inspect it. Also I am using a 12 front sprocket and 47 on the rear wheel. Also when its in neutral or any other gear the sound is gone...

[@EngineTuning]

Changing just the top end will have no effect on the gearbox - assuming that you did not split the engine cases. The balance shaft holds a weight to counter vibration...... this must be fitted according to the punch marks on the cogs - one punch mark between two. If this assembly is wrong...... the engine will vibrate. I would suggest you join: www.apriliaforum.com/ This way you can provide more information, and have many eyes on your problem.

[@EngineTuning]

+isak Langen The key is to check your gears and know where neutral is. When nip up the two cases, you then need to check that the crank rotates freely, and all the gears. Read Robin Hood's first post. When you've tested all is working, then continue with the assembly.

[@zacheale5397]

Hi I’ve just purchased a bike with an AM6 and seem to be having an issue with the gearbox. Starting from neutral and working up through the gears there is no problem, but trying to change down even in 5th / 6th to a lower gear often puts the bike into neutral no matter how many times I try and downshift. If I now were to stop and go up one gear I’d be back to first, could it be the selector fork slipping of something? Thanks!

[@EngineTuning]

Whatever is causing the problem will become apparent when you strip the engine and gearbox. When you have found the cause; perhaps you might return here and report your findings :) Good luck! :)

[@johnbombadillowns]

Hello! So I have some problems with where the shims should be. Could you make like a description on where the shims should be or like a drawing? Would be REALLY helpful!

[@EngineTuning]

How about this: www.apriliaforum.com/forums/showthread.php?224113-RS-50-Transmission-Assembly&p=2780665&viewfull=1#post2780665

[@johnbombadillowns]

Thanks alot!

[@olivereaster2778]

Hello, I know its an old video but need some help. Anyone know why I can't change the gear once the case it bolted on but i can once the case is off?

[@EngineTuning]

Typically, the shims are wrong, or incorrectly placed. Assemble in phases. Load a shaft, then assemble and nip up the cases. Keep checking. When all is correct, then final assembly with the crank shaft :)

[@tramppasamppa223]

if i do it your way, it doesnt go to second? only goes to free and first

[@tramppasamppa223]

when i got it to neutral the top gearings doent spin on your motor, but on mine does? why?

[@EngineTuning]

There can be 'oil drag'. Don't panic :D You have the gearbox in front of you. Now is the only time available for you to learn how it works. When you put it together, and close the crankcases....... it is over ;) Run through the gears.... hold the output shaft..... see what happens ;) You have the gearbox in front of you..... exactly as I had it...... you see everything. Take it steady and try to understand the gearbox Post back here, when you feel good. When the cases go back together..... there should be no mysteries.

[@MK-wx7uf]

is there a shim under the driving shaft to cover the bearing

[@EngineTuning]

www.apriliaforum.com/forums/showthread.php?224113-RS-50-Transmission-Assembly&p=2780665&viewfull=1#post2780665

[@liamwilliams7782]

Hey mate I love the room conversation 🤣 I have just watched a few of your videos and shame I didn't find you a few year back your detail on videos& how detailed you explain it is brilliant you gotta be a fuck tard to mess it up after watching these although I hoping 4years on you have realized if you move the shafts as your getting them onto the selectors it's so much easier if you didn't give it ago if your still kicking around in engine rebuilds top video geezer keep up coming you showed me a few Bobs thats easier so never to old to learn 🤣

[@EngineTuning]

Hahaha great to hear that the vids helped. Re the room conversion :D Watch out for the next vid ... it'll blow your mind (it's blowing mine whilst I'm doing it) :)

[@tricktvbmx728]

thank so Much!!

[@EngineTuning]

:)

[@tricktvbmx728]

+PlayF1 Net no like seriously this helped me so Much i found were all shims were supposed to be this time becuase i had a gearbox failure that got my gearbox totally clean bought every single sprocket to The gearbox and its like New now and thanks to this video i got my engine working 👍👍 i have had it in parts like 4-5times now before i got it working thanks!!

[@tricktvbmx728]

+PlayF1 Net no like seriously this helped me so Much i found were all shims were supposed to be this time becuase i had a gearbox failure that got my gearbox totally clean bought every single sprocket to The gearbox and its like New now and thanks to this video i got my engine working 👍👍 i have had it in parts like 4-5times now before i got it working thanks!!

[@EngineTuning]

I'm really pleased to have helped. It's great to hear that you've got your bike working.... and there is still plenty of warm weather. Good times :D

[@radg3dgaming861]

Do you have any clips of stator timing setting for these engines ?

[@EngineTuning]

No. Our engine assembled with a fixed timing... so we went with that.

[@radg3dgaming861]

PlayF1 Net ok thank you for the speedy reply

[@shaunhall1040]

Sorry its a late comment, i have to replace the shifter shaft on my am6, what would the easiest way to replace this be? would i have to split the cases? also what side do i take off to get the bit i want? thanks.

[@EngineTuning]

It's a full split. Prepare your work area. Have a number of containers to hand - I use meat cases - for different areas of the strip. A big sheet on the floor is another good technique for the first time. Lay everything in the order it is dismantled - keep your eyes open for o rings and shims. If you are forced to hit anything - always use a piece of wood between the hammer and what you are hitting. I use a copper and hide hammer. Check out my video series kzbin.info/aero/PLeHV-kNBKNNeLhnipp00LU6xcpqGtBSgr Oil the crank and bag it for the freezer. Reassemble without the crank, to test the gearbox. Then assemble with crank, and test again. If all turns smoothly, then continue assembly. You'll be fine, but good luck anyway :) Don't forget to subscribe - you know the YT subscriber rules kick in this month, and it will hit all help channels like mine ;)

[@shaunhall1040]

Engine Tuning Cheers a lot man, got the engine out now, going to clean it all over first, I'll let you know if I run into any issues, also subscribed! Thanks :)

[@EngineTuning]

Great.... lets hope it goes smoothly. Either way, it's all good experience :)

[@muddadeine31]

Ive got a problem with my gearbox. Ive put it together like this but when i try to change gears it sometimes works, but sometimes not. In both directions. And ive got a lot neutrals. But sometimes theyre not neutrals. Also my Kickstarter moves when i push my bike and ive put a gear in. Does anyone already knows what it could be? Also my oil pump doesnt pumps when ich kick it without turning my key. Should it be like that? Im not so sure. Thanks for your answers

[@EngineTuning]

There can be no doubt that the assembly was incorrect. You'll have to start again. Proceed slowly, and test assemble without the crankshaft installed. Only when you have the gearbox working, should you install the crank, test again, then complete the unit assembly ;)

[@muddadeine31]

@@EngineTuning got the problem, a snap ring in the cam with the one fork was loose an some gears didn't wanted to stay where they are supposed to be. Like that, changing gears was just luck.

[@thomaspschmidt]

I have a Generic Trigger, which is only allowed to drive 30km/h here in Denmark. A screw prevents it from using gear 4,5 and 6. We have recently bought the machine. The problem is that the screw does not work on this. It has therefore 6 gears. Is it possible that the pin on the shift drum has broken?

[@EngineTuning]

Hi Thomas :) This is interesting. A screw (presumably located inside the gearbox), is used to prevent the rider from engaging gears 4,5, 6. However, you can engage all the gears. That sounds like a win, to me (rather than a problem) :D My guess is that the previous owner split the engine and removed the screw ... but you may be correct, and the screw is broken. The pin on the shift drum, interacts with the gear change actuator. When the gear lever is lifted or lowered, the actuator pushes the 'pin and drum', clockwise or anti-clockwise. This rotation moves the shift forks, which causes the gear change. If the pin was broken, it would be impossible to change gear. :)

[@thomaspschmidt]

@@EngineTuning is the actuator pushing on the pins on top of the drum or somehow on the one big pin on the shaft of the drum? I dont understand what the pin on the shaft is used for otherwise.

[@EngineTuning]

@@thomaspschmidt There is only one pin. You can see it at the end of the video, where I use my hand to rotate the drum.

[@tramppasamppa223]

the gear drum is moving very hardly its kinda stuck i have to move it upn and down to get it move..

[@DeclanH250]

so theres no shim beneath the shift cam? think someone assembled mine wrong also i have two shims one goes under the output shaft but i cant find where the other would go any ideas?

[@EngineTuning]

The shift cam shim locates above the actuator pin (perpendicular to the shaft). The output shaft is shimmed at both ends. The gear change shaft is shimmed at both ends (about the actuator arm assembly). Don't forget to pre-assemble without the crankshaft (nipping up the cases) ... this, to inform you that the gearbox is not causing problems. ... and to check end play. Then proceed to full assembly; spinning the crank as you go, to confirm that it is not causing problems. Before doing all that ... don't forget to remove all high points on the case faces. Best of luck with the assembly :)

[@DeclanH250]

Engine Tuning appreciate your reply thank you and hope to see more videos soon?

[@EngineTuning]

Soon enough ... I've just got to up my game on 'production values'. The content has always been fine, but winging it (without a script) results in too much 'and ermmm' while my brain figures out the next sentence. It's a pain in the neck. ... just knocking out an informational video, isn't enough to get it on the push list (even if the info is useful). Luckily, for the younger generation (and a few Dad's) ... these early videos gained traction, so everyone can benefit. It's harder now, to spread reliable knowledge. Thanks for subscribing ... it helps :)

[@RandomStuffit]

Great vid! Thinking of opening up my am6 soon as it has a lot of trouble going into 5th and 6th gear. Do you know what the problem could be? It does go into gear upon a second try but usually doesn't go in and revs without moving like it is in neutral. Any help would be much appreciated thanks.

[@EngineTuning]

It's very hard to say. The clutch may be a cause... not sufficiently disengaged. From cold they are often a problem. Once warm they should be fine. If the clutch cable play is too slappy, consider adjusting it. Joining the forum would be a good idea. www.apriliaforum.com/forums/forumdisplay.php?21-RS50-Technical

[@RandomStuffit]

Engine is back together now and I put new crank bearings and seals in it as well as a new piston and clutch. The gearbox seemed to be in perfect condition and has done barely any miles. Problem is not fixed but I have learnt how to avoid it by simply lifting the gear lever twice when changing. I only have to put up with it for another 8 months anyway then I will get a 125cc. Your video helped a lot in the reassembly so thanks!

[@EngineTuning]

Thanks for those kind words. Sorry that the problem was never fully rectified. Life eh?

[@robinhood8119]

and please can you make a video to show how to assemble the gear shift shaft

[@EngineTuning]

robin hood I don't think there should be a problem with the gear shift shaft..... it is an assembly, and it slots in place. I have a video somewhere showing the shift shaft....... I'll try to find time to upload it...... but it only has one place that it can go. From your first comment/question....... I think your problems stem from not having the ball bearing to go on top of the spring. When in gear or neutral, the ball bearing is in a hole........as you change gear, the spring descends, and the ball bearing finds the next hole (you rotate the shift cam with the gear lever). Without the ball bearing, it will be difficult to find the next gear. Remember...... as you change gear, the ball bearing slots into the next hole. So without the ball bearing, you cannot change gear precisely. There is nothing else to do, but remove the motor..... split it...... and insert a ball bearing where it is required. My guess is that this will solve your problems.. I honestly cannot comment on what fell out of your gearbox (that look like nails). Please state the name of your bike, and the engine type, and capacity (if you know it). You should then join this forum..... in order to get further technical help: www.apriliaforum.com/forums/forumdisplay.php?21-RS50-Technical :)

[@robinhood8119]

PlayF1 Net Thank you so much,that little ball bearing was the problem hehe is a little different the mechanism but has a spring and a ball bearing like yours,is a minareli am6 engine on a enduro Malaguti 75 ks and has 75 cc with 6 gears,today i will try to assemble it if i will figure out how to put the gear shift shaft in place,i know that it fits in only one place but has a spring and idk how to put it,i will try to find a video on youtube and with that 4 bits that look like nails i will put them inside the shaft in a random order and hope it will not be a problem,i will let you know if i could do it,thank you.

[@robinhood8119]

PlayF1 Net they dropped when i opened the clutch side and i think there is another one that comes last and a ball bearing and all are from the output shaft

[@tramppasamppa223]

okay i think its now working correctly the ball bearing wasnt in hole on the bottom of the drum (?)

[@EngineTuning]

:) Well done. You can't leave anything out. Every component is doing a job. Don't forget that the shift cam normally works while pressing down on the ball bearing and spring.

[@vraber]

hello. today i rebuilded my engine (new crankshaft, bearings and seals.. then i put all back together and now i cant move gear shift shaft so i cant change between gears.. so i decided to open it again and i think i might found a problem.. but still i want some help.. i forgot to put 1 shim on.. and that was the one from 1:10.. is this why i could not move my gear shifter ? :) thanks ^^

[@playf1manager305]

+ Skillboost You need all the shims in the correct place. Perhaps you put the missing shim on the wrong shaft. If there was no problem before you dismantled the gearbox..... any problem that you have now, will be of your own making. Don't think that you are the first to make this mistake. Just put it back together correctly this time :) Good luck!

[@vraber]

+PlayF1 Manager fixed it today :) your video helped me :P thanks again.. i checked your other videos to.. i like them. grettings :)

[@playf1manager305]

+Skillboost Great news........ I can imagine that you felt good! Why not? Really pleased that I could be of help..... thanks for your compliments...... greetings to you also :)

[@RYYGE]

bro thankfully i found this bc my riejus gear box broke hella badly

[@EngineTuning]

Thanks for taking the time. I hope the rebuild goes well :)

[@RYYGE]

@@EngineTuning yeah the firts problem is get the engine of the goddamn bike

[@EngineTuning]

@@RYYGE Yeah it can be a grimy job. Make sure that you get the engine clean, before dismantling it ;)

[@RYYGE]

@@EngineTuning yeah that wont be fun job to do ::D:D:D:D::D

[@stlct6667]

hi the video its so help full but I would like to ask ya a question how can I find the neutron point ?

[@EngineTuning]

14:21 shows how to find neutral

[@stlct6667]

I think its cut out cuz I have no idea how did u moved to that point ?!

[@EngineTuning]

Turn the shift cam anti clockwise to maximum (first), then turn it one place clockwise (neutral). Watch the vid from 14:21 (simply click on this blue number and the vid will start at the exact point).

[@stlct6667]

Ohrite understand it now thanks a lot u helped me very much thx again

[@EngineTuning]

That's great. Good luck with the project.

[@robinhood8119]

Can you answer please at my last question ?

[@LocalAutist]

What can cause my gearbox getting stuck if the shafts are going freely when just the clutch or output shaft is installed but when both go in together they get "stuck"? Everything is shimmed correctly. I have noticed if I push the clutch shaft away from the casing it goes freely (when the basket is also installed), is something wrong with the gear shafts? The gearbox was working properly before I took it out for rebuilding

[@EngineTuning]

Hi Felix :) You have raised one of the huge areas of concern in the current education system ... something that men have been campaigning for, for decades. There was recently a petition in the UK stating: "We the people, demand that all children should be informed, that if a gearbox was working before it was dismantled, then it should be working after reassembly". The petition failed to attract sufficient signatures, and consequently, we remain with young adults leaving the education system, not having learned this valuable lesson for life. Shame :D Other than that ... I would advise that you be careful, when stating in your brain, that you have done everything correctly (eg. shims). Start again. Assemble the gearbox, without the crank shaft (as per normal assembly testing). During assembly, keep spinning the shafts, as you gradually nip the cases together. At the same time, keep feeling for lateral play in the shafts (ie. free play along the axis). The single most important thing to think about is:- "What have I done wrong" ;) With this mental attitude, you know damn well that you will easily discover what you did wrong :) I would say 'Good Luck' but in this case, you don't need it :D

[@LocalAutist]

@@EngineTuning there's only supposed to be one shim under the output shaft so I'm confused to what's wrong, the engine was never fully assembled because I was worried something was wrong with my gearbox, only the output shaft shim, output shaft, and clutch shaft were installed at that moment along with shift cam and all 3 forks with the shaft going down the 2 forks. Is it just how it acts when the gearbox is laying inside one of the cases? The shifter wasnt installed since I lost the shim for that one. I'm sorry if this these questions are stupid, this is my first engine rebuild and I'm trying to learn.

[@LocalAutist]

@@EngineTuning just had a thought, does the lip on the needle bearing matter if it's up to the shaft or to the crankcase? I think I installed mine with the lip up to the output shaft

[@EngineTuning]

@@LocalAutist It's hard to say Felix. Somewhere in the comments below, I believe I linked an exploded diagram of a Senda. ... but the key in this case, is 'simple trial and error', because it's not that complicated, if you are only assembling two shafts. Regarding the lip of the bearing ... I can't remember. However, it is unlikely that the needle bearing is 'handed'. Obviously, it needs to be seated correctly ... you know ... swarf and grit (hopefully not) :) The thing is ... the centre lines haven't changed. Consequently, it must be lateral play, that isn't playing. ... That is, assuming that the shafts are assembled correctly.

[@LocalAutist]

@@EngineTuning both good and bad news, it was skipping teeth until I tried putting the other case on with just the gearbox assembled and it went smoothly. But when I assembled with the crankshaft and sealant the clutch shaft is now completely stuck with the output shaft only moving around in neutral so something in the box must've hopped without me noticing. I'm suspecting a fork might've hopped out of the cam since I had to pull up the engine half since the case only went halfway and it pulled the gearbox with it slightly, and I was stupid and didnt think of it, so now I'm gonna have to take apart the engine once again, yikes I feel like an idiot now

[@tatuseppala8231]

I have lost 2 shims. Where i can order them?

[@EngineTuning]

You'll just have to search for shim suppliers. www.apriliaforum.com/forums/showthread.php?224113-RS-50-Transmission-Assembly&p=2780665&viewfull=1#post2780665 Good luck :)

[@tramppasamppa223]

is there shim on top of the output shaft?

[@EngineTuning]

www.apriliaforum.com/forums/showthread.php?224113-RS-50-Transmission-Assembly&p=2780665&viewfull=1#post2780665

[@kierancook9493]

How many shims are there all together

[@EngineTuning]

www.apriliaforum.com/forums/showthread.php?224113-RS-50-Transmission-Assembly&p=2780665&viewfull=1#post2780665

[@szupiszendvics7546]

How many gear is this?

[@EngineTuning]

Six gears.

[@gvidasklingeris7369]

Great video, but im having problems getting bottom shaft in place

[@EngineTuning]

Ha... the first time is always fiddly. Individually, if the shafts go in... they will also go in together. Don't force them. Good luck

[@gvidasklingeris7369]

PlayF1 Net i lost one of the small shims , can i proceed the assembly, if yes where shim is least importaint?

[@EngineTuning]

No, you cannot. These aren't just spacers, they are hard steel. But they do not just disappear. Which shim do you think you have lost?

[@gvidasklingeris7369]

PlayF1 Net I think i have lost one that goes under the shift fork, what will happen if i assemble without it?

[@EngineTuning]

Under the barrel with the slots? There is not one under that barrel. It has a shim on top. www.apriliaforum.com/forums/showthread.php?224113-RS-50-Transmission-Assembly&p=2780665&viewfull=1#post2780665

[@kettu94]

My first gear has disappeared, but now I'm rebuilding. How can I build it so that I have all gears?

[@EngineTuning]

Examine all the components carefully under a good light. Look for damage. Assemble, and test the gears, by rotating the shift cam (as shown in the video). Good luck, and keep us informed :)

[@kettu94]

yeah everything works when i put the two halves of the engine together, but when i try to tighten the bolts, the transmission doesnt feel right

[@EngineTuning]

Could be shims in the wrong place, or a bearing not fully home (if you changed any bearings). Check the sideways play of the shafts But you are following the correct procedure :) Plenty of people build the entire engine, and install it, only to discover a fault :(

[@almoo]

Rd50?

[@costel05rxy]

may be the problem ,one shim lost for not enter in 2-nd and up gears after assembling? it enter in first and neutral, the rest doesn't.

[@EngineTuning]

It is difficult to know why you have a gearbox problem. Perhaps you are correct, in thinking that you have lost a shim. How annoying! You must strip the motor again :( Remember to report back here. You can tell us what the problem was ;) Good luck! :)

[@costel05rxy]

I think i had opened and closed the motor, for about 6-7 times, trying diferent shim combination.now that i saw that link with shims positions,i will try again in the right way,but first find that lost big shim . i will return here if i made it.

[@EngineTuning]

The shims may be 0.4mm or 0.6mm (I've seen both sizes specified).

[@alexrhodes3471]

Hi I’ve followed this step by step, but when I put the other casing on the gear lever won’t move :( any ideas?

[@EngineTuning]

You need to test in phases. Assemble without the crank, and test as you nip up the screws ... see that the shafts turn, and that the gear lever works. Make sure that you have the shims correctly fitted.

[@alexrhodes3471]

Still no luck, it goes into gear without gear lever, soon as it is on it won’t budge

[@alexrhodes3471]

Just noticed it has not got a washer/shim on the small end side of the gear lever, could this be the issue

[@EngineTuning]

Well done for discovering this anomaly. Anything missing is certainly an issue. The plain fact is, that everything must be in place (correct position). There can be variants vis a vis shim thickness, between similar engines. However, if you are assembling, using the original kit, the only problem might be too much slack. Here is a link to a useful post for the Rieju motor. There are some differences in shim thickness - I don't have the data to hand - but these are the shim positions. www.apriliaforum.com/forums/showthread.php?224113-RS-50-Transmission-Assembly&p=2780665&viewfull=1#post2780665 If it doesn't load in chrome, then try Firefox ;) Note the springs at play on the shaft. The shim acts as a bearing surface. If it isn't there, then there is no bearing surface, so it is unlikely to function as planned. Remember ... these are highly tuned engines ... everything is pushed to the limit. Before anything else, you need to get everything installed correctly. Good luck with that, cos I guess you will now be hunting down that hardened shim. :)

[@alexrhodes3471]

Thanks for the help, I’ll be looking for it tomorrow when it’s brighter :)

[@muddadeine31]

What's that needle in the shift cam for?

[@EngineTuning]

The gear change actuator.

[@muddadeine31]

@@EngineTuning is it supposed to be a stopper that it doesn't moves too far? could you please describe the purpose because no translator delivers a good translation. Thaks a lot 😁

[@EngineTuning]

@@muddadeine31 It's the gear change actuator ... look at the gear change shaft - it connects to a U shaped lever. This U lever rotates left or right, pushing on the pin, rotating the shift cam, which in turn changes the gears.

[@muddadeine31]

@@EngineTuning I don't mean the pins on top of the shift cam, I mean the one wich is inside the hole. They're called spring pins i think. Even tho, tanks for helping me out.

[@EngineTuning]

@@muddadeine31 Try spending more time, when preparing a question ... what hole, what spring pin? Why not upload a video?

[@TossForTheWin]

this gearbox are defective?

[@EngineTuning]

Are you asking if this gearbox is defective? ..... No it is not defective...... it is functioning perfectly.

[@trevordalzell8775]

Whats a good web site for parts for an am6

[@EngineTuning]

Ha!... that's a good question. It depends on your priorities, and disposable income Prices can vary dramatically between sites. A component such as the output shaft can cost €15 or €75 - possibly from the same manufacturer (who knows). I paid €15 and mine is fine. The killer is always transport costs... it can destroy your morale. That €5 component that you forgot, might cost €15 delivered. List everything that you are going to need (a spread sheet is the best), and keep adding to it. Use the exploded diagram that each site uses, for the exact part name and number. Set up a favourites folder, then search for the parts, and save the link with a memorable name You might find that two suppliers can cover all your needs. Check their payment terms, some do not use paypal. A good starting site is easyparts.nl It's multi language, and has a huge range of components. Make sure that you know where the €5 postage sites are scooter-center.com offers this... great for carb components ;) Good luck... and don't forget to subscribe (and thumbs up) ;) kzbin.info/www/bejne/nnTbeKOLbMupd6s (carb tuning intro) :)

[@jordanb2769]

how many washers(shims) are in the gearbox in total? 3 or 4?

[@jordanb2769]

+Jordan Berry one at both ends of the 2 shafts?(4)?

[@EngineTuning]

+Jordan Berry Have a look here: www.apriliaforum.com/forums/showthread.php?224113-RS-50-Transmission-Assembly&p=2780665&viewfull=1#post2780665

[@jordanb2769]

+PlayF1 Net Thank you :D what bike was this engine taken from (am6) its in loads of 50 geared rs50,mx etc

[@EngineTuning]

+Jordan Berry This one was an MX50 2004

[@tramppasamppa223]

please open the motor and do tutorial how to test gears and dont skip

[@tramppasamppa223]

motor is now on the frame and the front chain sprocket doesnt move... thx dude..

[@EngineTuning]

WTF man! I told you to test turn the motor when you assembled the cases Then test turn the motor when you first tighten the cases Then test turn the motor when it is all tight. Why? Why would you fit an engine in the frame, when it doesn't turn? Listen tramppa..... I'm not doing the job for you. You have to do it yourself. This job is well within your capabilities. If you keep testing, at different stages of the assembly..... you would know exactly at what point you made a mistake. ..... oh.... the motor has stopped turning.... what have I just done wrong? You know..... like that. Other people can do it..... so you can do it. ..... and what's this 'thx dude' when you fucked up? Is this somehow to help you deal with it...... like as if I misadvised you..... you know...... somehow it is my fault. 'Man up'...... and deal with it.

[@tramppasamppa223]

yes i know i blaed u about me doing it wrong XD i was just so angry :( havent rided for 3 weeks but hey, i got it working now everything works perfectly i did ride 2km test ride :DD

[@EngineTuning]

Okay.... cool..... well said...... and well done in the end. Great to get back riding again eh? I've just come back from an evening ride as well. :)

[@tramppasamppa223]

ill shoutout you if u help me to get my engine work

[@oasvensson1]

my gear shifter gets stuck when im shifting....

[@EngineTuning]

Thanks for the comment, but... It would be much more interesting to read, if you provided the historical context. Perhaps the gearbox has never been stripped, and the problem has got worse. Maybe you stripped the box and made an assembly error. Maybe everything was fine, until one moment, when it started to fail. In addition, you could outline your on-road solution ... ie. how do you then change gear? ;)

[@oasvensson1]

@@EngineTuning after iu blew my cylinder my gear shifter started to get stuck. Lit no respons at all. i have never stripped the gear box. Soooo my solution is that i put a trampoline spring at the gear shifter and to the frame so i have little spring fealing. Btw sorry for bad english=)

[@EngineTuning]

@@oasvensson1 Never say never, but typically, there would be no connection between a failed piston, and the gear-change. You will need to split the cases and examine the gearbox. It's a nice project :)

[@tramppasamppa223]

police stopped me 3 days after rebuild... they tooked my lisence plate and fine of 48e... and i have to now drag it to inspection and put it goes 45km/h

[@EngineTuning]

:( That's very bad luck. Re-fit the 12mm carb.... and put a big washer in the exhaust manifold, fit the old barrel and piston.

[@tramppasamppa223]

original carb is 16mm XD i got the license plate back alrdy

[@EngineTuning]

great news :)

[@nojusdomarkas3572]

Why could am6 engine have more than one neutral

[@EngineTuning]

Worn components perhaps.

[@robinhood8119]

PlayF1 Net I found ,the order of that ''nails'' does not matter,some people have only one ''long nail'' and after that a ball bearing and last another short nail,now i have another problem,i put the gearbox and everything at their place and the shims and after i tight the bolts of the cases the output shaft is stuck and i tried to change the gears and sometimes i can spin it but very very hard and when i losen the bolts it spins easy,what could be the problem ? the shims ? i put at every shaft a shim and at the drum.

[@EngineTuning]

robin hood okay, I think I understand what you call 'nails'. :)These are the 'thrust rods'. When you pull the clutch lever, it pushes the thrust rods, and forces the clutch apart. The ball bearing between the thrust rods, allows the first rod to spin (on the ball bearing). Okay.... so you've understood that :) Gearbox lock-up on assembly..... Options: You have the shims in the wrong place The shims are too big You have used too many shims. I presume that the shims you are using, are the shims that were originally in the gearbox. In this case, you have them in the wrong places. SOLUTION: Assemble the gearbox and cases WITHOUT the engine crankshaft. This simply makes life easy for you. :) Try different shim positions....... each time, screwing the crankcases together, and checking the gearbox movement. (you must do this because you didn't record where the shims should go.) After trying a few times....... you will find the correct positions. Keep going...... you can do this :)

[@robinhood8119]

PlayF1 Net Thank you very much for all the help,i remove one shim from the output shaft from the side of the clutch and now it spins.

[@EngineTuning]

robin hood Congratulations........ a difficult job, well done. :)

[@robinhood8119]

PlayF1 Net Now that the engine is assembled when is in first gear the front sprocket is spins very hard and when is in the rest of the gears it spins but not hard,what could be the problem ? on one end of the input shaft or the output shaft must be two shims one after another or the nut of the clutch basket is too tight ? because before i installed the clutch the gears were changing good,i hope you can answer me.

[@EngineTuning]

robin hood Use this set of diagrams www.apriliapartsbuyer.co.uk/parts/mx-50-2004.page-2 to help you locate all the shims....... there are two sets of pages with diagrams of gearbox and clutch assembly. www.apriliapartsbuyer.co.uk/parts/mx-50-2004/primary-gear-shaft www.apriliapartsbuyer.co.uk/parts/mx-50-2004/gearbox-driven-shaft-i www.apriliapartsbuyer.co.uk/parts/mx-50-2004/gearbox-driven-shaft-ii Check numbers 6, 9, 11, 12, relating to washers on the 3 diagrams above. You must test all the gears, before final engine assembly.This means screwing the crankcases together, usually without the crankshaft. If all gears work....... you can then split the cases again, and insert the crank etc. Screw the cases together, and test the crankshaft rotation, and all the gears again. You now know the gearbox and crankshaft are fine! When you assemble the clutch..... tests again. If there is a problem, then you know that fault lies with the clutch assembly (if all your washer shims are fitted correctly) :)

[@lupin1389]

quanti ne ho aperti è chiusi di questi motori avevo il fantik TM 80 mi sembra si chiamasse cosi erano sempre usate di 3/4 mano le rifacevo nuove dal motore al telaio era un divertimento andare a caprera a fare le gare contro le apilia tuareg 50 allora ci si divertiva cosi mi ricordo che erano indistruttibili le facevamo cadere da un piccolo burrone na non si rompeva nulla , la prima che ho avuto mi ricordo era 4 marce poi trovai il motore a sei marce , lo aprii cambiai tutti i cuscinetti i rasamenti le molle i selettori che negli anni 85 si trovavano ancora , da li incominciai a fare il meccanico.

[@EngineTuning]

+ David Aversa Good times! :)

[@pierpaolorossi5629]

Ngul a tu

[@EngineTuning]

Lots of translations for Ngul, but I don't know which is correct, or even the original language. Can you expand? :)

[@tommybradley4088]

Oh yeah so put in everything but the selector shaft u doughnut

[@EngineTuning]

Hahahaha - nice humour Tommy :D

[@5245jah]

Instructions unclear: lost some of the shims while trying to assemble

[@EngineTuning]

That is a tough lesson to learn ... I feel for you :( Keeping the shims in position is a key part of disassembly. Ouch!

[@ThaKillaInstinctHD]

thanks zemmer u sahbi me tabon yemek thanks

[@EngineTuning]

So how are 'you' interpreting that statement.... tabon yemek?

[@ThaKillaInstinctHD]

+PlayF1 Net wollah kankerzemmer sahbiman

[@EngineTuning]

Ha ha ha it looks like you don't know what you are saying. Do you not realise that these are swear words, in street language. Have you read them somewhere... tabon yemek?