Shimano Nexus 8 Speed Hub - Dissection! Evisceration! Destruction!

I disassemble a Shimano Nexus 8 speed hub to see what's inside.The hub is a Shimano Nexus SG-8R20. It also had the option roller brake installed. The hub is probably as complicated as a car transmission. I ain't never getting this thing back together again! LOL!
Shimano Nexus 8 Speed Hub Reassembly - Putting It Back Together...:
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[@RJTheBikeGuy]

For more bike repair videos hit the subscribe button ► bit.ly/SubRJTheBikeGuy

[@allencrider]

Just think: someone actually designed this thing.

[@glasswinder]

It's amazing, you know.

[@crocodilecrox3758]

Just think of the math and physics they had to apply

[@NirreFirre]

Reverend Al Japanese. Just look at the higher end watch movements from Seiko, or an eighties high end compact AV gear from Sony... Damn, they beat German, Swedish, Swiss engineering straight! (being a Swedish one myself)

[@thomashughes_teh]

It took more than one genius to put that together the first time. Blame it on Leonardo da Vinci for starters.

[@allencrider]

@@thomashughes_teh LOL

[@jclohesy]

Thanks for doing this. I love the Shimano Nexus gear, so incredibly robust compared to derailleur. I now have immense respect for the engineering, and will never resent paying for a gear hub. Our family have done thousands of miles on hub gears, and I won't go back. Thank you again for a very honest job!

[@flpirate45]

It's incredible on how our minds have grown sense the invention of the wheel. Just making all those little parts and putting it all together and creating that piece of machinery. Loved the video, Thanks.

[@blomy67]

I think you need to accept the challenge of trying to clean it up and get it back together . No need to pack it full of grease just some oil to lubricate but we need to see it work again .. Please

[@nadinegoodman6576]

I agree - it shouldn't / mustn't be packed full of grease

[@suitknol6604]

Hahaha that's my job. Do one every two, three weeks or so. I'm a bike mechanic

[@jfkcamelot]

@@suitknol6604 How did you learn to do this? Even for a an expert bike mechanic like RJ the Bike Guy this is almost above his head.

[@suitknol6604]

@@jfkcamelot in the Netherlands, bike mechanic is something you can actually study at school. I went to school 3 years, every Monday, and worked Tuesday to Friday. I learned how to disassemble hubs there, among a lot of other info. I wouldn't call RJ an expert bike mechanic because not everything he says is strictly true, but he is 100% better than most. He can also do other stuff I don't have any experience with.

[@janezjonsa3165]

@@suitknol6604 Dutch, who else would have a school for bike mechanics :) Thumbs up!

[@trekkie9942]

Wait, is this the first time RJ hasn't been able to put something back together?! NOOOOOO!!!

[@Flippingbiscuits]

I strongly believe he uploaded this video in reverse

[@barryhernandez6428]

There's no purer pleasures in life than completely disassembling a mechanism to see how it works. At least that's my humble opinion. Thanks for a great video.

[@TimHollingworth]

This reminds me of the time I pulled apart my 24mm-105mm Canon lens! It was a 3 dimentional puzzle from hell and all the time trying to keep the glass free from finger prints. I did get it back together but was tempted to put the 100's of pieces in the bin! I too would love to see this amazing geometrical puzzle put back together again and hopefully working too.

[@RJTheBikeGuy]

kzbin.info/www/bejne/gH_Yqql_j9t2qNU

[@goijehudim5798]

I never heard "here" so often in my life!

[@squaller9254]

*_H E R E_*

[@sleepmark]

65 times~ish

[@pottacoola]

i was telling him to shut up in my head lol

[@litvinenkoalexander5331]

I started seriously to do mathematics when I was 13, now I am 43. The whole 30 years I permanently improved my math skills. Now I am a math teacher at University. I saw very complex theorems and proofs. But, I must say, that the construction of this rare gear hub is very complex. I am very much impressed by people who invented it.

[@timgarland8619]

Three observations: 1. It really makes you appreciate a cassette and derailleur system. 2. This has a large "ick factor"! Have you considered a parts washer? 3. Great advice at the end about taking one apart!

[@RJTheBikeGuy]

I actually have a parts washer. I need to dig it out and replace the solvent in it. I was cleaning the parts in my ultrasonic cleaner which is pretty lightweight.

[@event4216]

As soon as I rode IGH I appreciated time saved on cleaning multiple cogs and low running chain. This is a low end hub, I just checked Campi Record 8-sp cassette alone costs about 2/3 of this hub. Shimano 8sp cassette is about 1/3 to 1/4 of price, though.

[@AlmostBipedal]

Just as we all suspected, it works by magic! You've just doen what must of us would love to do, but wouldn't dare do so with our own hubs. Thank you.

[@truckertom3323]

RJ, i do not think that you are the kind of man that would let this kind of challenge beat you, i think there is for sure going to be a Eureka moment, and the put back video is some thing for the future, in the immortal words of Sean Connery, 007 "Never shay Never, Kah peesh"

[@aceboogie8986]

Tom Thats honestly what i was thinking 2 rj is not going to let this beat him

[@d44102]

just play this video backwards to figure out how to put it back together lol

[@edwardwb3430]

Big brain time

[@thetedster7812]

Crazy complicated for a mass produced bike hub.

[@Flippingbiscuits]

Take a shot if you hear “in here” lol awesome video

[@monztrluvr]

Hahaha! I noticed the same thing! Great video nonetheless!

[@lissandrofernandez8750]

Right here?

[@GaijinInvader]

That's what I was thinking too! 🙉

[@tekknorat]

You evil person, now I have alcohol intoxication and need to go to hospital to pump that all out.

[@jasontirado6313]

I’m going to leave a comment “right here”.

[@marblox9300]

OMG - this is one complicated gizmo. I'm glad I saw you take it apart because now I don't have to do it.

[@nathangant7636]

IGHs with more than 5 gears are usually oil-filled and oil changes are mandatory. Change with hub gear oil before and after 1000 miles (no previous oil change). Then change oil every 3000 miles. (the first oil change is at 600 miles). Use only Shimano SG-S700 Oil in the Alfine 11 hubs. Also use waterproof grease in the hub to prevent premature failure.

[@a.v.k.2852]

Seems suspiciously like an extraterrestrial technology.

[@andycapo9you]

It is the same as a 8 speed automatic, but all in 1 axle! And way tinyer! I have done the same with a Sram I-motion 9, and it is a nice challenge. Thank hell I had a good day and did not throw the fucking thing thru the window, It still works after 5 years and lots of miles after. When you reasemble, bath it in ATF, Works wayyy better

[@Joseminario]

Lol.... "It works with magic" that is one complicated piece of machinery and u are one patient dude. I would have thrown that in the trash halfway through crawled in the fetal position and started sobbing.

[@litvinenkoalexander5331]

It is fascinating to see how engineers have been able to invent such complex details.

[@bullwhipjohnson8247]

You would need a shop manual. With, an Exploded View. That will help you identify parts, determine their condition and, the order of assembly. Good luck with this mission. If, you decide to accept it.

[@vlodek-193]

I had the same situation with the seven-speed Shimano hub:) SACHS / SRAM 3/5/7 hubs (the older ones) are so simple and ingenious in construction. Imagine what must be inside the Alfine11 hub - a horror for a mechanic:D Greetings from Poland!!!

[@maciejnowak1993]

Pozdrawiam...

[@vlodek-193]

@@maciejnowak1993 Ja również pozdrawiam!🙋‍♂️ Teraz to już siódemki od Shimano mam rozpracowane w 100%, a ósemki wydają się nawet prostsze w budowie od nich. Dzięki YT można sobie poradzić nawet z tymi "nieszczęsnymi" blokami sprężynowymi. Mam też specjalistyczne narzędzia do tych piast od Shimano, smary i oleje również.☺

[@iggysixx]

I've taken these apart succesfully (and put them back together again). There is a certain point after which you should probably stop disassembly (or you're gonna have a bad time ;). Halfway, you come across some double spring-loaded thingie. And I HAVE managed to put that back together and back on without the official tools, but it took me several hours over several days.. And a loooot of patience ;) Anyways - Nexus gear hubs are my favorite. VERY reliable, very little service required. Just make sure you use the Shimano recommended greases (the rollerbrakes too - they have Moly based grease for those with a certain viscosity. (I tried lithium grease, but holy sh!t - suddenly my brakes didn't work anymore at high speed) Oh, and look for the dots imprinted in the metal gears (easy to miss) - on the first (?) planetary gear set (3 gear wheels), the dots need to face outward. Exactly the same as eachother, or there will be problems with gear alignment... That proper gear alignment makes it so you can shift from 1 through to 8 while standing still (it's pretty sweet) Oh, and use the proper shifter. One made for Nexus 8 (Nexus 7 shifter works too - you just don't have the heaviest gear available to you) Oh, and use the proper err... (I think they call em) 'anti-rotation washers'. Those things that lock the axle in place (to keep everything in position); They have different colors for Nexus 3, 4, 5, 7 and 8. Nexus 8 is 1 gray, 1 black Got Nexus hubs on 3 of my 4 bikes, and I reckon I might be the only one in Amsterdam who likes servicing this system (:

[@darrengarvie8832]

Just to ask is there a road bike shifter that can be used for them?

[@asbjrniden3621]

These hubs are just mechanical nightmare nesting dolls, once you think you've reached the end there is another split ring and 50 more parts... Very interesting to see, but beyond what I want to attack on my own, so thank you!

[@RJTheBikeGuy]

LOL!

[@kleberguirado]

Hi, i'm from Brazil. Now, i want to see you clean and assembly this again... 😁😁😁

[@paxvid]

Thanks! I wanted a faster bike at one point, mi city bike was old and slow. Found a Bianci Milano with a nexus 8. It was slower.... but way newer 😅 Even though used I couldn't resist, the internal mech was almost worth it by itself as a conversation piece 😄 It's been the sweetest ride forever and am glad I've seen some of the mechanical engineering magic out of my head and in real life 👍 Nice project partner, keep it up 🖖

[@MattExzy]

I see what's behind the naming. It's the nexus point between sane and insane.

[@KennyMinigun]

There are special tools produced/sold by Shimano for servicing these hubs. The tools simple but are kinda model-related, so you need to google proper tool part numbers for the hub. Hope this helps you re-build the hub, because that would be just wonderful (looking forward to seeing the next episode).

[@3DPDK]

An old "Billy Backyard Mechanic"'s trick is to lay out on your cardboard, each part removed in the order they were removed. You could even group them according to the area they were removed, ie; left side, right side, inner drum, etc. With the cardboard, you take a Sharpy pen and number each part and make any notation that helps you remember your conclusions as you disassembled it. You are lucky that you have a decent video detailing how you disassembled it. Just reverse the procedure. The funny thing is when reverse engineering you learn just as much if not more by putting the thing back together.

[@EDerable1]

When you take it apart, carefully place your parts in the right order, watch closely how the rings and springs and other stuff sits on the axles. When you put it together again work backwards, no need for manuals. Begin with an old one.

[@johnpossum556]

Interesting. I came very very close to buying one of these then bought the Ebike instead. Now I understand why overseas they call them roller brakes. It looks like a roller bearing sprague clutch like use in drills and cordless screwdrivers. The hub itself looks like it might be built to be 9 speeds but loses one because of its configuration. I think once I'd crank on it'd definitely break. Thanks for the peak inside it RJ.

[@creatiph]

I like the idea to service bikes myself so I'm going to stay away from this mechanical nightmare. Thanks !

[@sagehiker]

I just built a winter bike using a Shimano 8 speed hub. I love I got to watch someone else deconstruct one. This video satisfied my basic curiosity. I do most of my own bike repairs and maintenance, but these hubs, no internals for me.

[@bb1039]

the tech is old, but still so brilliant. who ever came up with the mechanism for shifting and holding the pinions in place should be named every time

[@saqrsalem186]

Funny ( here ) sound I laughed a lot when I heared you laughing at the end. Thanks for sharing a good moment. I think it is similar to car's gear box where the clutch isolates speeds.

[@Keroppikun]

Wore my Nexus 8 out after two and a half years of city riding my Bridgestone belt bike, here in the country that makes them. Popped along to my local bicycle shop, the place where I bought it, and moaned for two or three minutes. They got on to Shimano forthwith, who happily agreed to replace it with a new unit free of charge, even though the one year warranty was out. Bike service is good, here in Japan. Changing a rear tire with a belt and such remains a pain, mind you!

[@wolfmanradio]

It looks like Shimano used automotive design and built a miniature automatic transmission. I wonder which transmission the Nexus is based on. Thanks RJ for another great educational video.

[@OctogonOxygen024816]

It runs on a Toyota's variant of an auto tranny

[@markhill2279]

Had this hub laced into an old '85 Raleigh Renegade to replace the 7 cog cluster...ran the bike to about 6k miles and hub developed some play in the body and needed a new rear sprocket....took it to a local bike shop for some work and got it back..never to be the same. Later I went with a Sturmey Archer 8 sp hub, put 10k miles on that with no complaints...so far.

[@brianmerryman6743]

RJ, this is why I replace these and don"t even try to fix them. To many moving parts, somebody had a lot of time on there hands to design this! No thanks but interesting. Keep the awesome video's coming!

[@robgifford3766]

Wow,, does anyone want to try to put this thing back together? I'm looking at an 8 speed internal hub. Can't imagine fixing something like this. Much respect for having this knowledge.

[@meadows408]

What a greasy mess, no wonder it wouldn't work. I had one of these on a Bianchi Milano and loved the way it rode. But, I had a flat on the rear and it took me a full day plus lots of busted knuckles, scratched fingers, etc to get it fixed. Great engineering but not for the diy guys like myself. I applaud your courage in taking this apart. I'm fool enough that I would try to get it working again once the grease and dirt were eliminated. Keep up the videos, they have helped me a lot.

[@KarlosEPM]

Finally something even RJTheBikeGuy finds hard to repair! Lol, thanks for your work sir!

[@JackMitchell404]

I much prefer the linear shifting of a Sturmey Archer. Really you should be looking for 4 different gears in there, hub gears usually have a direct drive then each speed below that is paired with one above, so a 3 speed hub will actually only have 1 gear train, it just uses it in both directions and has a bypass for Normal. Interesting video, though I too would like to see it fully cleaned so it can be observed, surely your video can show the order and orientation of the parts as they came off

[@paulawestcott7228]

Time to re design bike gear shifter here, there everywhere here. Your patience with excitement is great and with clear vocals here.

[@robertengland8769]

Actually, nice to know I'm not the only bike mechanic in the world. Thank you for the instructional video.

[@bruceabe3139]

thanks RJ...I've got one sitting around that i was gonna do the same thing...rip it apart to see how it ticks...you just saved me hours and saved me from getting my hands greasy! Thanks keep up the fine work!

[@utterfuckwit84]

I wonder whether you need to think in binary, RJ... 3 palls gives 8 configurations: 000,001,010,011,100,101,110,111 - there's your 8 gears

[@RJTheBikeGuy]

I know binary. But I don't think they work like that. I think only one of those inner gears can be stopped at a time.

[@utterfuckwit84]

I know you're a programmer so I know you'll know binary. seemed to me that the fact a couple of palls popped up, then one, etc... seemed very binary to me straight away and would make three palls enough for all eight gears. just a thought anyway.

[@RJTheBikeGuy]

I think there is also an inner and an outer drive somehow.

[@dkercher984]

isn't binary 1 and zeros in groups of 8 pairs not 3 but it does look sorta like hexadecimal only 3 so tridecimal ish lol

[@RJTheBikeGuy]

@@dkercher984 No, binary is just a number system like decimal. 8 bits is a byte in computers. But that doesn't define binary. I see what he was saying. There were three pawls, that could be either up or down (on or off, 1 or 0).

[@JurajGrossmann]

it is like I hear him. gentlemen, welcome back to the shop, today a treat especial... same approach he did for panasuckit scruediver, put it on the healingbench and dont loose parts. i am sure you will find it most challenging to try again and again. as the audience wisely commented, it is water that caused the premature death. rohloff is sealed with regular oil change. i dont think after the wear tear, being it loose in the hips it is salvagable. seek to see your vids on these advanced toys. you could develop your own ".. in a vice" end slogan

[@jonnyspitfire]

Yep - I've got one and your Video confirms me darkest fears... mine isn't shifting from 1-4 - working fine 5-8 but I ain't going in there - It'll just end up in the Trash... Thanks...

[@robbchastain3036]

This could be like the 38th minute of a VH1 Behind the Music video--"And then RJ began disassembling bicycle components without bothering to put them back together again." Rut row :)

[@BrandtRalf]

The gear block can be taken apart fully. You allready had been on the right track. After remivong the lower bearing shafts. trurn the upper gear wheels so that the uper bearing shafts moves down to the lower gear wheels. next you can remove the upper gear wheels. this allows you to remove the freewheel. next the lower gear wheels can be removed. Now the inner gear wheels can be removed too

[@TheJoePavlik]

God damn murder scene

[@RJTheBikeGuy]

LOL!

[@1paultv22]

This is when it's nice to have a heated parts washer at the home workshop. Brake clean is also a must-have.

[@Prxpagandalf]

Now that was intense! 😅 It was like watching a guy solving the impossible puzzle.

[@odroid4058]

Thanks for the video, it's great to see what's inside this thing! I have been riding with a nexus 8 hub on one of my bikes for five years now, and it is very reliable overall, especially as I keep the bike outside. One year from new I had the shop I bought it from service the hub as it was "slipping" into a neutral gear (which should of course not exist) when set to gears 5 or 6. When riding this can be dangerous, as you suddenly lose traction. The shop told me they just tightened up the bearings as they were loose, and that indeed fixed the problem. I guess they tightened up what looks to be the bearing cup you see at 1:07 . (I think you can just about see the bearing race from the outside of the housing at 1:13 and then from the inside at 1:24 ). I suppose with the whole stack of internal parts being loose, the pawls were able to slip sideways out of their sockets somehow. There is some great information on Sheldon Brown and from Shimano, but this problem of a loose bearing leading to a sudden neutral gear does not appear to be addressed in any of the "adjustment" information I found on those websites.

[@thibod07]

Those Shimano nexus hub are surely amazing and sturdy. I would never venture disassembling one like you did but it was surely interesting to see you doing it. I will leave you alone with my bike! 🤣😏🤣🤣

[@jeremygraves3645]

Thank for this video. A few parts on the outside of the hub got loose as I was removing the rear wheel to fix a flat. Your video showed me how they were aligned before I goofed things up!

[@crocodilecrox3758]

Thanks RJ ever since ibsaw that thing i wanted to know how it works. At least i saw how the inner gears rotate and how the fingers clip on and off.

[@AndyinMokum]

Bloody hell, what's it packed with? It looks like a grease mud emulsion. I wouldn't be surprised to find out it worked just fine after it was cleaned and lubricated with the correct lubricant.

[@danielraymadden]

On a large white marking board draft in squares in numerical order, reverse engineer placing each item in squares 1 2and 3 etc with video replay I'm sure you could put it back together. Watchmaking and transmission planetary gears are fascination art forms and will remain future tech.

[@johncombs4105]

I purchased a Gaezelle Tour Popular 8; that has that hub. It also has roller brakes(please do a video on them). The gear set works like a car automatic transmission. But, it's very small and complex like a Swiss watch.

[@anthonyschmieder3174]

😨 I guess that's the internal gear trade-off: it's easier to keep it clean, but it's impossible to service it. I like the idea of internal shifting, but after watching this I'm happy with my derailleur systems. Thanks for the video!

[@m.r.659]

Couple years ago I was trying to do it in new oil, so got it out, couldn't put up back together by myself then took it to bike repair shop, they gave up, so bought used one, and it is working till this day. Only upgrade I've done, I changed the sprocket for less teeth so a bit quicker.

[@coffeepot3123]

Just landed a lady bike with a 4-speed coaster hub, (100 dollar bike!) Looked like it was from the early 2000's and all original parts. tires still good etc, no rust. Some rusty screws that need replacing and the chain is in dire need of a cleaning. Anyways great content!.

[@arto1313]

I just gave my hub oil bath with motor oil 10w40 and gave some grease to bearings during putting hub back together.

[@recepgunoglu4058]

i like the way you say the words 'here' and 'little'

[@LauriAP]

Dirty hub, cleaning is quite good idea and maybe organizing parts. I found exploded drawing and operational quide. Shimano spare-parts list, I had 2 depending to shaft length, the right one had right number of nuts, so there are many drawings within the same model too. My hub had black grease and it seemed in good condition. That was not problem. My problem was pitted bearings, so I kept transmission as it is, didn't remove safety-clip or that thing holding planet gears. Transmission is serviceable. Sellers manual guides to dip it in transmission oil, not dissassemble, but grease is much easier to apply when gears are dissassembled. It is big operation. And the shifter sleeve is the core of transmission so if you manage to figure out how it works raising pawls and rachets driving gears at each gear, you should find out if there is anything wrong with it, nevertheless it is dirty, the brown grease is contaminated with water or dust or something, oxidated maybe. White grease at hub walls indicates that original grease is white. I got white grease that is official, but there is also black Nexus grease. Dissassembling is easy, you can do it in minutes with one or two hands when it is clean and ready and so is assembling, but now you took the axels it is learning procedure if you make it unit again.

[@kelvinmulder]

Hi, I am currently following a 3 year study for bike mechanic (I am from the Netherlands) and have to learn every single part of multiple gear hubs and how they work. Its a pain... Lol. Try to take apart a 7 speed shimano hub. Its even more complicated, and more moving parts in every gear. Only reason can be so they wear quiker. Anyway, these hubs need a maintenance oil bath with special (blue) oil every now and then. Never use normal grease! Cheers

[@RJTheBikeGuy]

Yes, I showed that in my next video where I tried to put it back together.

[@kelvinmulder]

@@RJTheBikeGuy ah yes! Currently watching that video. I have a lot of respect for you putting that thing back together. Love the channel by the way!

[@benhuygh9086]

I actually dis and reassembled the shimano rollerbrakes on my bike it took me over 10 turns to get them working properly again. watch out for flying springs!

[@thrasherx9319]

Wow. Your intuition and aptitude is truly impressive. Thanks.

[@brianheard4565]

Had one on a Trek 7400 and documented all distances travelled. After 12,000kilometres the gearbox failed. Reason: the large ball bearing on the sprocket end fell apart - the riveted sheet metal cage broke. Replaced it with a new gearbox 'cos I luv the transmission, and the bike.

[@jamesmiller113]

Excellent - I have one that's beginning to grab when freewheeling, so it needs taking apart to clean - your vid's shown the final safe point! Degreasing then plenty of fresh copper *should* be enough!

[@XxXnonameAsDXxX]

I've never seen such a complex thing in any bike part ever. This is the future if you ask me, this car level complexity.

[@jamesporter5630]

“It works by magic.” Ok. Moving on...wait, hey wait a minute. That’s my answer, can’t be RJ answer. I turn to experts like RJ to demystify. The room is spinning, vision narrowing, dark, getting darker, argh....

[@redbearrc6706]

I have a problem with the 8 speed and it doesnt goes well in 3 4 5 gear but 1 2 6 7 8 no problem. I greased and it works a bit better but I did not disassembled it like yours. Yes I find it also magic.

[@gibboj]

well done my m8 , i struggled to understand how the sturmy archer 3 speed one work`s . 8 speed well over my head

[@charlesatwell9976]

Thanks for your honesty! I was just wondering ''How is he ever going to remember how all those pieces were assembled'' When you confessed that you probably wouldn't be able to. Haha.

[@2966710]

It wasn’t disassembled with a view to reassembly. It’s a very small but similar to an automatic transmission. An auto trans engineer would very carefully lay things down so it could be put back the same way. In my experience do it ten times then you could rip it apart, throw in tub mix it up and reassemble no problem. Just need the opportunity to get familiar with them. But probably there’s no commercial reason to, hourly rate and risk of having to guarantee work I doubt anyone is going to fix; except the curious that like a challenge.

[@capmidnite]

It would be cool to see a Rohloff disassembled. But I believe they're factory service only.

[@Peo_Sahlin]

The hub is full of grease where it should be a thin special oil from Shimano. Probably why it didn't work. A cleaning and oil bath with Shimano oil (part no Y0029801A) would probably have solved the problem.

[@bruceabe3139]

an engineering marvel! Magic indeed!

[@ravinperera4255]

What kind of alien species designed this..amazing!

[@BenZoet]

I have one of these on my bicycle, and yeah, it won't go down into the third, second or first gear. Not really a problem: the fourth gear is light enough, like the first gear on a car. They're finnicky, and I'ld have opted for a three-speed had I known this. Three-speed are good enough for a transport bike.

[@christo930]

It looks like water got into this hub judging by the color of the grease. Did you get it back together? There is a guy on YT who rebuilds these things. I agree about the magic. The physical stuff is so complicated. There are some smart people working on this stuff! Just think of all the old machines built in the late 19th and early 20th century that can do whole drawings entirely on this type of stuff! They were built by literally 1 guy who often had very little schooling! Geniuses!

[@robertwloszczyzna]

Who is The Guy on KZbin send the link please I need to service mine but dont have a clue how

[@Thecrazyvaclav]

Great video,loved the sudden realisation from you that it wasn't going back together,or come apart any further

[@SkipFlem]

I wonder if you can use ATF as a lubricant?

[@danniboi187]

I have one of these Shimano Nexuses on my Raliegh bike for 8 years now. Always wondered what magic was happening in there.

[@marvinmartion1178]

Use mineral spirits, it's oil based.it needs serious cleaning and regreasing!

[@that70sschwinn]

Rubik's Cube😬

[@Prodoping]

From Buenos Aires.......your videos are very goods!!!!

[@NeilSnapePhotography]

Just bought an bike with a Nexus 7. Best it lasts, and agreed these remind me of automatic transmissions in cars.

[@e.stgo.7998]

That's more complicate than a car transmission🤯, too many tiny parts😱. It's like a SWISS watch. THANKS FOR YOUR ADVICE 👍👍👍👍👍

[@LauriAP]

Sheldon Brown had guide for nexus hub servicing and operation. My Nexus 7 was pasman, there you can find how it works shifter sleeve, gear shifting cam, return spring and so. I studied it quite long time before I opened the hub and didn't open it much after all. Reconditioning bearings is my job at the moment, polishing and hardening or covering races with nitric or something a poor man could do.

[@RenZ089]

Is anyone turned the HEREmetr on, like THIS?

[@Randolph_M]

I have a Nexus 7 in my bike that I use for urban commuting. The shifting of gears is very pleasant when it works. Often it doesn't work. The adjustment of the cable on the grip shifter is tricky, and it doesn't provide the accuracy that the gear mechanism requires. The visual aid of aligning yellow lines is difficult to use because of dirt accumulation and scratching on the transparent plastic cover, which are impossible to avoid in everyday use. The problem sounds petty and superficial, but it can prevent the hub from working correctly when the cable gets adjusted wrong. That small but important detail looks like a case of thoughtlessness in design work, like a case of engineers not treating the user interface of their product as a serious design task. I bought the gear hub in 2017, I wonder if Shimano has done anything to fix those issues.

[@raginmund6927]

I did disassemble one of these 8 speed hubs for a friend about 3 years ago. Only took me like 5-6 tries (2days) to get it back together. Sad thing was that there was too much water damage inside to get it in working order and my friend ended up buying new insides for it. Anyway the whole bike was maintenance nightmare, there was always something wrong with it , especially that EBB bottom bracket that had to be tightened like every other week. Long story shot after that ordeal i have not been a fright to disassemble any bike parts.

[@xtremegohorse]

best vid ever made in this chanel. i completely relate to the final reaction.

[@zakdk1]

......yes RJ we need a video on the roller brake!!!!!!!!!!

[@vladthebikeguy4763]

Once you'll put this together and make it work like new, you'll be a magician. You can do it , it will take some time, but you inspired us all ;)

[@NallePu83]

japanese engineering

[@jtables7138]

There are some other companies from other countries that have complex geared hubs. The Rohloff 14 speed is from Germany, and the Sturmey Archer 8 speed hub is English.

[@iankstanley]

@@jtables7138 Sturmey Archer was purchased by Sunrace in 2000. Sunrace Sturmey Archer Inc. Taiwan