I've consulted 6 bikeshops for help to assemble this geared hub - and got no help at all - they where not able to help me. They couldn't get any spare parts, I was told, and they didn't know how to fix it for me, and they could not get any help from Shimano. Your video did make the what was needed..... really god and detalied - and now it works perfect - Thank you very much.
This video saved me! I have done this work some 15 years ago and thought it would be easy to take it apart and reassemble. Boy was I wrong. It took me a couple of attempts before I understood how much I should twist that spring in the beginning of the video. Kudos!
Great video with all the nessesary steps. Thank you. This model I believe is SG-7C18. Mine is and all the parts looks the same. I dissasembled mine and thought it should be easy to assemble it again. I found another instruction that I thought was good enough, but concluded that I was missing some parts, for examle the tiny pins in the beginning of the video. And searching for more information I found this exellent, very informative video that confirmed my suspicions. Now I have to take apart my hub, make two new pins and a simple spring, and follow these instructions.
The retaining clip you put in at 26:20, I can not get the parts to seat far enough down the axle to get access to the slot for the clip. It is out by about 1mm. Any suggestions?
This is a fantastic video and thank you for making it. At 5:20 - 6:20 there is something more than meets the eye on what you are doing here. I only have 3 of my 7 gears after putting it back together and think it's because of this spring assembly. Could this be what's wrong? Could you make a video explaining what's happening in that minute?
2:54 - i believe it is to be noted: that long, semi-revolving part is left in "base/open" position, with that spring socket facing upwards. Then at 3:03 it starts the first "springy" part - did you get that slight twist as seen from 3:25 ? Note, at 3:34 the long part is lodged already where the semi-revolving way ends (springforce-bound). Spring's start bit and end bit is at opposite sides of axis (bits are about 60° apart, so twist is about 120° = 180°). Then another, 180° twist (now to 360°, with almost a complete rotation of tension built), then another 180° (540° total now). Then that "cap"-ring, and then the part you referred to from 5:20 .. The next spring's start and end bit is overlapping (0° apart) and he only builds 90° tension, then just wiggles it down till the spring's start bit sits perfectly at the bottom corner of that flap.
At ~5:45 you can see that the bent hook of that spring (which can be seen at 5:10, installed into the rotating piece at 5:20, and protrudes inside it) gets stuck inside the groove of the underlying piece. As a result, the "ears" of this rotating piece cannot rotate past this groove (compare 5:48 and 6:19). So he starts wiggling both the rotating piece and the underlying piece, trying to get that bent hook beyond that groove, so that the rotating piece can rotate a little further. At 6:19 you can see that he managed it.
I ended up figuring it out by feeling the movements same as the way the guy was doing it and mine slipped in. Put back together and have all gears and works perfect. This was 2 years ago now.
I appreciate you posting this video very much as Shimano is doing their best to... withhold the information needed to service those hubs and to dicourage people from overhauling them. Manuals, if available at all, have mostly small and blurry pictures in them, the instructions are confusing at best and pictures are frequently mislabelled. For example, "Shimano Nexus 3-Speed Hub SG-3C41 Service Manual", section "Assembly ...", step 2 - instruction says: "While pushing the two pawls C on the driver unit (...) place the driver unit onto the axle unit. Note: Be careful not to let the pawl pin B fall out" - and then there's a tiny and blurry picture underneath, with "Pawl C" and "Pawl A-1" annotations pointing at some indistinguishable elements on that low-res joke of a picture. But I digress and whine here; my main point is there are many different models and variants of those hubs on the market (again, confusing users - a favourite pastime by Shimano, I guess...), where some of them are "partially compatible", and some are "hardly compatible at all". (Heck, they couldn't even make the Inter 3 hub, the most basic of them, "internally compatible" regardless of the length of the axle!) So, the problem is, that this assembly instruction is accurate (and useful) only for SOME of them "Nexus 7s" out there.. Mine is SG-7C20 (w. fixed metal dust cup on the "driver side" (right hand one), while yours has a plastic removable cap. Are they "compatible"? Well, if I only knew the model number of this hub I could search for it - but I'm not going to take mine to pieces to only find out "oh dear... we're not in Kansas any more...". I tried to spot any model number appearing during the video but could not see any (or am I missing something?) - so, could you please state what specific model of Nexus 7 you're assembling here? Thanks in advance...
@Will Swift Thanks, but this is what I know already (and knew when posted my previous comment). The question is whether they are COMPATIBLE - i.e. similar enough so THIS assembly video can be used for "MY" hub. However, the author doesn't seem to care to provide a specific and accurate info.
Thank you so much! It would be great if you could do a full disassembly video with the same style, and possibly add comments or voiceover to explain more what you are doing.
High I wander if you can help with nexus 7 hub on drive side after you put in the cone you put in a washer thing with lugs that go on the bit that sticks up my problem is mine isn’t sticking up so wen I try install gear cable there no tension
Здравствуйте! У меня при сборке оси shimano nexus sg c3000-7c нижняя пружина при повороте ее на 36о гр. не влезает под юбку кольца, на которое опирается основание другой пружины. Если довернуть еще на 180 гр, то все получается собрать, но при этом переключение передач нормально не происходит. Не хватает миллиметра, чтобы при повороте на 360 диаметр пружины достаточно уменьшился и все получилось собрать. Но ведь на 1,5 оборота нельзя закручивать нижнюю пружину. Что мне делать? Может укоротит на 2 см пружину?
Man you are a godsend! There are almost no other resources that focus on the gear shifting mechanism on the axle. Thanks for this indispensable video!
I've consulted 6 bikeshops for help to assemble this geared hub - and got no help at all - they where not able to help me. They couldn't get any spare parts, I was told, and they didn't know how to fix it for me, and they could not get any help from Shimano.
Your video did make the what was needed..... really god and detalied - and now it works perfect - Thank you very much.
This is the best video of Shimano Nexus 7!
The sounds of birds, bees and the odd jumbo jet while assembling a nexus hub. All it needs is a voice-over done by David Attenborough :)
Great video, with bonus bird song in the background. Beautiful 👏
This video saved me! I have done this work some 15 years ago and thought it would be easy to take it apart and reassemble. Boy was I wrong. It took me a couple of attempts before I understood how much I should twist that spring in the beginning of the video. Kudos!
This is poetry! So many mad props to you! Now I am informed to take apart one of my Nexus or Alfine rear hubs would truly be a mistake!
Extremely good video. So extremely detailed. Thank you so much...
I suggest however that the description tells the exact shimano model this is.
Great video with all the nessesary steps. Thank you.
This model I believe is SG-7C18. Mine is and all the parts looks the same.
I dissasembled mine and thought it should be easy to assemble it again.
I found another instruction that I thought was good enough, but concluded that I was missing some parts, for examle the tiny pins in the beginning of the video. And searching for more information I found this exellent, very informative video that confirmed my suspicions.
Now I have to take apart my hub, make two new pins and a simple spring, and follow these instructions.
Dieses Video zeigt eine Profi Arbeit! Super und Dankeschön 😊
Very detailed and clearly visible.Thank you!
Excellent video with close ups!
Thanks for the detailed work
And the garden sounds.. Very cozy to work with.
Very nice vide. I suppose the should be some lubricant on all parts. What do you recommend?
The retaining clip you put in at 26:20, I can not get the parts to seat far enough down the axle to get access to the slot for the clip. It is out by about 1mm. Any suggestions?
Just perfect! What about grease inside the hub, it looks dry?
Oh heck! I could have found this earlier. Thanks a lot! There's a puzzle waiting for me downstairs...
This is a fantastic video and thank you for making it. At 5:20 - 6:20 there is something more than meets the eye on what you are doing here. I only have 3 of my 7 gears after putting it back together and think it's because of this spring assembly. Could this be what's wrong? Could you make a video explaining what's happening in that minute?
2:54 - i believe it is to be noted: that long, semi-revolving part is left in "base/open" position, with that spring socket facing upwards. Then at 3:03 it starts the first "springy" part - did you get that slight twist as seen from 3:25 ? Note, at 3:34 the long part is lodged already where the semi-revolving way ends (springforce-bound). Spring's start bit and end bit is at opposite sides of axis (bits are about 60° apart, so twist is about 120° = 180°). Then another, 180° twist (now to 360°, with almost a complete rotation of tension built), then another 180° (540° total now). Then that "cap"-ring, and then the part you referred to from 5:20 .. The next spring's start and end bit is overlapping (0° apart) and he only builds 90° tension, then just wiggles it down till the spring's start bit sits perfectly at the bottom corner of that flap.
I have the same issue. I only have a speeds now
At ~5:45 you can see that the bent hook of that spring (which can be seen at 5:10, installed into the rotating piece at 5:20, and protrudes inside it) gets stuck inside the groove of the underlying piece. As a result, the "ears" of this rotating piece cannot rotate past this groove (compare 5:48 and 6:19). So he starts wiggling both the rotating piece and the underlying piece, trying to get that bent hook beyond that groove, so that the rotating piece can rotate a little further. At 6:19 you can see that he managed it.
I ended up figuring it out by feeling the movements same as the way the guy was doing it and mine slipped in. Put back together and have all gears and works perfect. This was 2 years ago now.
I appreciate you posting this video very much as Shimano is doing their best to... withhold the information needed to service those hubs and to dicourage people from overhauling them. Manuals, if available at all, have mostly small and blurry pictures in them, the instructions are confusing at best and pictures are frequently mislabelled. For example, "Shimano Nexus 3-Speed Hub SG-3C41 Service Manual", section "Assembly ...", step 2 - instruction says:
"While pushing the two pawls C on the driver unit (...) place the driver unit onto the axle unit. Note: Be careful not to let the pawl pin B fall out" - and then there's a tiny and blurry picture underneath, with "Pawl C" and "Pawl A-1" annotations pointing at some indistinguishable elements on that low-res joke of a picture.
But I digress and whine here; my main point is there are many different models and variants of those hubs on the market (again, confusing users - a favourite pastime by Shimano, I guess...), where some of them are "partially compatible", and some are "hardly compatible at all". (Heck, they couldn't even make the Inter 3 hub, the most basic of them, "internally compatible" regardless of the length of the axle!)
So, the problem is, that this assembly instruction is accurate (and useful) only for SOME of them "Nexus 7s" out there.. Mine is SG-7C20 (w. fixed metal dust cup on the "driver side" (right hand one), while yours has a plastic removable cap. Are they "compatible"? Well, if I only knew the model number of this hub I could search for it - but I'm not going to take mine to pieces to only find out "oh dear... we're not in Kansas any more...".
I tried to spot any model number appearing during the video but could not see any (or am I missing something?) - so, could you please state what specific model of Nexus 7 you're assembling here? Thanks in advance...
@Will Swift Thanks, but this is what I know already (and knew when posted my previous comment). The question is whether they are COMPATIBLE - i.e. similar enough so THIS assembly video can be used for "MY" hub. However, the author doesn't seem to care to provide a specific and accurate info.
Best video i have seen so far. Thanks!
Thanks to this video, I'll give it a try!
Great video! Mine jumps in 7 gear, (2 yellow marks aligned in 4th)
Any suggestions other than total hub replacement?
Thank you, just what I needed!
Thank you so much! It would be great if you could do a full disassembly video with the same style, and possibly add comments or voiceover to explain more what you are doing.
th-cam.com/video/CRNYETaqyk0/w-d-xo.html
just play it backwards mate
Saved my a** mate! Thanks
Can you do a Shimano nexus 7 with a disc brake please?
Wow! So well explained. Thank you!
High I wander if you can help with nexus 7 hub on drive side after you put in the cone you put in a washer thing with lugs that go on the bit that sticks up my problem is mine isn’t sticking up so wen I try install gear cable there no tension
How to fix coaster brakes that have lost braking power?
Perfekt
Здравствуйте! У меня при сборке оси shimano nexus sg c3000-7c нижняя пружина при повороте ее на 36о гр. не влезает под юбку кольца, на которое опирается основание другой пружины. Если довернуть еще на 180 гр, то все получается собрать, но при этом переключение передач нормально не происходит. Не хватает миллиметра, чтобы при повороте на 360 диаметр пружины достаточно уменьшился и все получилось собрать. Но ведь на 1,5 оборота нельзя закручивать нижнюю пружину. Что мне делать? Может укоротит на 2 см пружину?
hi, do u have the detailed for the 7 speed shifter? i have one disarmed.
What a beautyfull stuff !♥️!!
What grease is recommended for this hub on reassembly?
on the bearings, white grease, NLGI 0-1
the rest is dipped in shimano hub oil.
Cool!
What is efficiency of Nexus 7 hub? I heard they are more durable than Nexus 8 hubs, is that true?
mine did over 50.000km without any maintenance so far
Thanks :)
Really good.
W. Czasie. Jazdy. Przeskakują. Tryby co. To. Za. Awaria czy. Smar. Kole. Może. Przeszkadzac
Naucz się pisać normalnie, oraz ustaw biegi zgodnie z instrukcją Shimano.
BEst video for Nexus 7. Pay extra attention to what happens between 6:00 - 6:19 . If you dont do this step correctly the hub wont work properly.
Thank you sooo much
fantastico, inteligente video
Koe