Just a heads up. I had my alfine 8 for two years and started developing problems 6 months ago where certain gears in the higher rang (5,6,7,8) would not engage smoothly and where the 8th gear began continuously clicking. . Adjust was spot on. I just fixed the problem today by changing out the cable and it works perfectly. I opened the hub 8 months ago and everything inside was pristine and well greased. The reason why changing the cable worked so well is that once you get into the higher gears on the alfine the tension in the shifter cable increases causing it to stretch more and be less accurate in the higher gears. This is many alfine users a have issues in the higher gears. Cannot believe that the cable change was so simple, easy, cheap, and effective. Should be the second troubleshooting step after checking adjustment. Best of luck to everyone!!!
Was your cable evidently damaged before changing? Or did it look good? My cable looks like brand new, but bike is 4 years old (but it was not ridden). Is it possible that cable has streched without using (or used occasionally)?
My cable looked brand new. A cable can stretch and still look new. If you left the bike unridden for a long period of time and the bike was sitting in a higher gear then I believe the cable could have still stretched because the higher gears put a lot of tension on the cable.
I ordered the Cube Hyde Pro yesterday... omg would a normal gear-changing-chain-thingy have been a better option? I have literally no clue about bicycles.
Pibbles 'n Bits Thanks for this,about changing the cable. Mine didn’t work from its inception because I’m new at this but still have some knowledge about how and what makes stuff work. I knew the cable was the problem and on till the broken ends stated protruding the shop keep telling everything was okay and I’m hard on the equipment.We changed the cable and I changed bike shops.
I had a bike with the Nexus 8 (not Alfine) and it covered 50 000km ( I cycle to work). It only needed a new gear cable once, and finally needed a new face plate because part of the face plate that holds the cable end, broke off. Otherwise trouble free and no maintainance! Highly recommend for recreational/commuter cyclists. There is a minimal loss of efficiency that would affect a race cyclist, but not noticeable for regular cyclists
Juanuary 18, 2020: Dan, I'm going to upgrade my Atlas Cargo from the Sturmy Archer 3 speed to the Alfine 8 speed for some long trips this summer. I've been a mechanic my whole life and can fix anything if I've got a manual. Now, I've got a complete internal parts breakdown with a dynamic display of internal parts and their function that talks to me !!! Awesome work Mr. Dan !!! I can make a tool kit just for this and be able to repair it roadside if need be. Store it in my phone and play it back when I need to. Thanks a bunch!
I have the Alfine 11sp hub on road bike, a tad heavy, but no deraileur, exact shift/response, and works excellent. Expensive, but after miles of riding, glad to have made the purchase. So far, 3 yrs use, very durable.
no boat, they shouldn't be noisy, i bought my alfine 8 based on this video....and it works great! the only thing i miss is the speed of my road bike...........i was asking Dan if i could install a 52 or 53teeth chainring in replacement of the 42t chainring i have now and replace the 18t rear sprocket for a smaller one in order to go faster......
Dan, that was the clearest, easiest to understand explanation of how this hub works, that I've ever heard! I'm very impressed you were able to convey the information so simply. It would appear that Shimano have designed and built a very easy to use system. I now have only two questions. 1 - Is it sturdy enough and made with high enough quality materials to last a good long time with minimal maintenance? 2 - How can I get one without selling everything I own to afford it? Thanks for taking the time and obviously a great deal of effort to produce a video that almost anyone with some mechanical knowledge can use to understand this system. Shimano should have you on staff as a technical trainer!
+Thomas Jowett Thank you for the comments. If used for it's intended usage, kept properly adjusted, the hub should give very reliable service for a very long time. Maintenance requirements vary, with more attention required if used extensively in foul weather conditions.
Thanks again. I'm not going to admit to the number of times I have watched this video but it has done the trick. I understand how my Shimano gears work. Through watching your videos I have a good understanding of my 3 and 5 speed SA hubs and now my Shimano hub. Great video.
Awesome video explaining the workings of an internal gear unit! I've watched around 30 videos on this subject (produced by other people) and Dan Burkhart's is the best I've seen thus far. If you're not familiar with the names of parts then it would be a good idea to thoroughly acquaint yourself with them first, and re-watch the video one or more additional times. I run a Bicycle Collective in St. George, Utah, and I'm referring all my people to this video. Great work, Dan!
3:1 difference between low and high ratios but only 8 ratios total, which means they are spread out widely, which is undesirable to many people, including me. Imagine on a piano for example, spanning 3 octaves using only 8 notes (7 intervals). Instead of being only about 5.9% apart, each ratio is about 17% apart from the neighboring ratio(s). That is like a double shift to me (skipping a ratio in between). I need close ratios, as sometimes I feel I need something between 18 tooth rear and the next ratio which is either 20 or 16 tooth rear. This leads me to my conceptual design. Have all 21 tooth ranges in the rear (from 10 tooth to 30 tooth inclusive), but since that will be so wide, have the front sprocket/chainring move laterally to keep the chain properly aligned. That way you have 3:1 difference between highest and lowest ratios, but have 19 more close ratios in between. That is my ideal design and I am waiting to see if someone makes it in my lifetime. If 21 cogs turns out to be too wide, then just reduce it to whatever can be made to work, such as 15, but then make the difference between high and low ratio only about 2.5:1, to keep the intermediate ratios close, or maybe let the user select their own set of ratios, following the manufacturers compatibility rules for them.
Based on my research, a less than 15% difference in gear ratios don't make much difference in pedalling effort (+/- 3%). This is based on my city riding with some hills (Los Angeles). I believe this is why mainstream sprocket clusters on rear wheels have differences ranging between 12 and 18% (eg, 8-speed 11-32 or 7-speed 14-28). Plug these into Sheldon Brown's gear calculator which shows the % differences and you'll see. I understand that as speed increases, you need closer ratios than 15% because of increasingly greater wind resistance which makes pedalling harder. Also racers or highly athletic riders may benefit from closer ratios to squeeze as much speed as possible from their cadence. Also, Rohloff 14-speed has about 14% difference between all gears. I believe manufacturers have done their research on this.
This systems is a highly advanced mechanism. I just bought a L train bicycle and I was amazed how it works compared to standard gear systems. I learned alot of information on how this system works thanks to your video. Keep up the good work teaching.
I use Shimano 8.The someone on ebike. So happy with it. I've always hated the old sproket type. Can't say enough about. Never had any trouble with over 5th km and working great.
Finally. Finally... Been wracking my brains looking at pictures and trying to understand how epicyclic gearing works, and finally you've made it come clear in my mind and I can see it now. At last. Thank you thank you thank you!!
In my Alfine the plastic cage for the roller bearings broke. Due to a lack of spares availability the hub was junk. Taking it to my LBS they were not interested in touching it so I had to dive in. It lasted about five years, the lack of support was very disappointing. Great video though 👍
Question: Could that part have been 3D printed in Carbon Fiber Nylon? I'm working on starting a belt drive ebike project and making everything digitally controlled with an arduino, including shifting. Watching this video my impression was this would last forever if well maintained, and well you just killed that. If it could be 3d printed it wouldn't be a problem and I would be ready for the failure. Also, do you think that part could be replaced with a soft metal like aluminum? If you can make a cad design of the part, China will machine them for you cheap.
@@mborowski2010 Hi Michael, to clarify the cage was for the ratchet pawls not the bearings as I wrote earlier. The pedals locked up with the rotation of the wheels and then eventually the hub locked up. I am not an engineer but to change the material it is made from you would need something that won't wear and contaminate the hub but not wear down the parts it interacts with.The lack of spares for the hub and the bike shops not wanting to touch it was the worst, that hurt. 3D printing I will investigate, I hadn't thought of it so cheers for that👍 PS. The other consideration is i may have had a lemon, reading some of the other comments people seem to be having a good run with theirs but again the parts and tech support would be worth investigating.
@Dan Burkhart, perfect narration; pace, tone, and articulation. Matched with both still and video visuals, this is pretty hard to improve upon. Thank you!
You did a terrific job with this video. Anyone should be able to understand it. Superb. I want one now that I don't have to disassemble it myself. Only I wonder how much weight / stress that clutch can handle. I'm about 170-175 lbs so I'm sure it should suffice. Thanks again for a great "exploded view" and breakdown.
Excellent! I didn't follow every detail - will watch again at least one more time to get a little deeper - however I have a basic understanding now thanks to this video. I have never run across any other explanation like this and I truly very much appreciate it! I put over 10,000 miles on my former belt-drive Nexus-3 bike, and I recently upgraded to a new belt-drive bike with an Alfine-8 - approaching 1000 miles on the new bike now. I had not understood the two-range, four-ratios per range architecture before I watched your video. Your explanation makes it clear why 5th gear should be the most efficient (least drag), as this is a direct drive with no planetary sets in the power path. I think I can feel this when I ride. After this, it would make sense that 1st, 6th, 7th, and 8th are the next most efficient, having only one planetary set engaged, either just the low-range reduction set (1st gear), or just one of the three overdrive ratios (6th, 7th, and 8th gears). Finally, 2nd, 3rd, and 4th involve two planetary sets in series, the low-range reduction set and one of the overdrive ratio sets, and so would seem to be the least efficient. I believe I can feel this while riding. One thing which I think is very noticeable while riding is the increased efficiency (reduction in drag) in changing from 4th gear to 5th. Thanks to your video I now understand that there are never more than two planetary sets engaged in series in any gear setting. Approaching 1000 miles, I like the Alfine-8 a lot. My new bike has 700c wheels and came set up with a 50 tooth "chain ring" and a 22 tooth rear cog. With 170 mm cranks I like how this choice of "chain drive ratio" balances the extent of the low and high gears. For sure, 1st gear could be lower - I can't take on just any hill, but the ones I normally encounter are manageable. I do like where 8th is at and feel like it's a pretty good balance on my commuter bike. When riding, the gap between 5th and 6th is the one I sometimes wish were a little closer. It's not uncommon for me to run into a riding situation where 5th gear feels like I'm spinning out but I can't make the force needed to hold 6th gear. I end up having to drop back to 5th and slow down to keep a comfortable cadence. Now that I understand how the three overdrive ratios are all based on separate sun gears, I'm not sure why the design couldn't be made with more uniform gear step sizes. However, I suppose it's also possible the the 5th to 6th gear span is driven by the necessary commonality with the 1st to 2nd gear span, where a closer ratio would not be as desirable compared to the design as is. One request would be to provide the gear ratios as exact integer ratios (gear tooth counts) vs. the provided decimal approximations. I suspect studying the integer ratios may provide insight making it clear where the difficulty is in realizing a design with a more uniform set of gear steps. If you have these integer ratios in the form of the actual gear tooth counts, and could provide them here in the comments, that would be awesome and much appreciated. My first bike had a Sturmey-Archer 3-speed. I loved that bike and missed it when I "upgraded" to a Schwinn 10-speed. Now decades later I'm back to riding bikes and back to internal gear hubs. They are so cool. One thing I notice while riding is that I'm shifting gears very often while riding because shifts are so easy allowing a nearly continually optimized cadence vs. pedal force. I don't know if modern derailleurs are this quick and effortless to shift, but if not I'd miss the super easy gear shifts if I went to a derailleur bike. Thanks again so much for the excellent, informative, and highly useful presentation! Joe
Thank you for this video. I personally have nexus 8 premium in my bicycle, and it is awesome, I'm making over 400 kilometers per month with a minimal amount of service... actually the hub itself doesn't need any kind of service, at least for now. I don't know if I fully understand how it works, but at least it's not science fiction now :)
I have ridden nexus 8 for three years and it was great experience. However if you pedal hard it makes some grinding noise. So it better fits for relaxed ride. Nothing too aggressive.
2 years ago i tried this bike with this gearbox It's very easy and smooth and it's better than the traditional gears on another bikes It's mini gearbox but with high torque at 1st gear and at 8th gear with high speed I really would by one of these bikes
watching this video I was transported back to my young and care free days. That looks like a dyna flo sprag set up. WOW, what goes around comes around.
All I can say is ; holy crap! All that for a bicycle ? How much is it ? About the same as a automobile transmission ? I like it ,but it must be cost prohibitive .
@@boracay12 they are kind of expensive--but it's neat technology. My elliptigo uses this. And adjusting it is really easy (vs. tinkering with the screws and tension adjustments for external derailleur).
@@boracay12 available from about £137 www.google.co.uk/shopping/product/11263393959198283395?q=Shimano+Nexus+Alfine+8+speed&biw=1920&bih=969&prds=epd:7591863736334054134,paur:ClkAsKraX5MzwupjuvOmaxZkW1EWH2t8MWV8dokebV-RyvEXkjbx9QOcKjgN5muBu_nBdR9eXTb8o0GXFc4jhuemJVI1A-_xsDzmImnzsSWBCRp6BwHbnR1u-BIZAFPVH71R1IjT-v7btaBTDDxd070QEA9S9w,prmr:1&sa=X&ved=0ahUKEwi29KOQ9dDtAhWKRhUIHSEvBl4Q8wIIwwM
@@david197407 ok thanks . 13k peso . My cheapy chinese mtb with 29 " wheels and 21 gears ,( working fine ) cost 6.2 k peso . But very interesting set up .
Also its possible to double the amount of gears by having a twin or even triple front sprocket and derailer (using a thinner chain so there is some play when changing the ratios on the front sprockets .A triple gives 24 speeds .
Thank you so much from those of us who could understand a semi complex drive train flow path. I would like to rate your video a A+. Viewing it a second and third time does greatly help to understand the drive flow path knowing the rest of the several mechanisms are not engaged. I now understand the unit. I started looking for answers when my Alfina would not shift. I think my handle bar shifter is at fault. Some times my thumb lever action has no reaction to the hub assembly. I am still looking to see how the handle bar shifter works. Any advice would be greatly appreciated. Thx again Dan.
Sir, you nailed it. You might actually save my gearhub. I mean, without your video I'll probably at some point try to figure out how it works and the outcome might be a complete disaster. Thanks very much.
I am happy to see a video with some detail! The best video on youtube on this subject. Greetings from a bicycle mechanic in Amsterdam (the capital of cycling).
You gave a great explanation of the hub. Thank you! I just test rode a bike with this hub and was curious how it worked. I have questions about durability under high torque situations...I'll seek those on other videos.
Wow, that was an amazing video. I understood everything, I don't think I have ever done that with a video like this aside from the old 1950s automotive principles videos from GM. The only thing is I wish you had either a better camera angle or a wider field of view lense. Being able to see just a little more without it being so cramped would in my opinion, greatly increase quality of presentation from a viewing point of view. Other than that this video was about as close to damn near perfect as I've seen so far on RU-vid. I haven't checked the channel to see if you have more videos akin to this, but if you do then hit dog, I'm gonna have to subscribe to this. Great video, thanks for the informative, non-bloated education. I really enjoyed it.
If you happen to have a rohloff on hand sometime.... love to see one of those. I’ve refurbed Sturmey 3 speed stuff, and that’s easy enough to understand. Never opened up anything more complex.
Wow, well done. I've seen other videos on this device, but none really explained how it works. I have one of these and love it. It's always better to understand it.
I've had a (very early model) Rohloff for 15 years now, and I'm afraid it too has an Achilles Heel: the shifter cables emerge from the twist-grip at right angles and are prone to damage in everyday use. Plus the cable box seems quite capable of warping and being damaged. The flexible cable housing that enters the hub on some newer models was a response to this problem I suspect. I've replaced the shifter parts three or four times now. They're not cheap. The Rohloff hub itself is a marvel of course, and seems still to be going strong without any issues, despite heavy urban use (trailer, cobbles, kerbhopping...) I'm about to rebuild it for the third time: rim's shot. Would I buy one again? No. Thinking of going back to Sturmey-Archer in fact (seriously). Now that is a proven technology!
outcast566 He said he didn't like the shifter cable with his. I wonder if this is a problem with the current models.. must be or he wouldn't be looking elsewhere.
Great video, good explanation of the internal parts.. Waiting patiently to put 2500 kms on my hub and then I will be pulling it apart and putting it back together.
Thanks for explaining..had to watch a couple parts over and go back to the illustrations in the beginning to grasp but, you explained it well. Be cool to see a CAD animation.
Dan, thanks for the explanation, great video! It really helped me to understand and appreciate the function of geared hubs. Now in the future you should make a comparison video of the Nexus and the (much more expensive) Rohloff Speedhub ;)
I see all the comments about confusion - I'd be too if I didn't actually go hard core and take one apart and figure out how it works. Unless you're a gearbox designer or a full-time inquisitive gearhead, of course it is hard to follow without touching one!! There's something about diving into some things to understand them. Some things don't lend themselves to explanations in class or video, but many things do (in my estimation). I do have to say that he did a decent job as hard as the subject was to follow.
Shimano jad a three speed that was used by Raleigh from Nottingham England. I loved those planetary hubs way better then derailleur system, so precise compared to derailleur.
Thanks for the video. i thought it would be like this inside; explains why 5th gear feels the most natural to me. I have this hub on my carbon belt drive system and it feels really nice (acceleration and power transfer).
Magnificent video; very well explained and at a good pace too! I must add to the noise of people saying that you sound like the narrator to a 1950s/'60s training/information video.
Thanks much for the educational video. I have a few suggestions for newer videos: 1. Make sure the audio doesn't overdrive (there's a bit of this at the beginning) 2. Light up the shooting well enough. It's currently a bit dark 3. If you can, borrow a camcorder that offers manual focus: As usual with autofocus camcorders when shooting up close, the camcorder will often focus on the background, making the foreground dim 4. Make sure the part you're showing is actually within the camera range (around 6:00)
I had a three speed internal hub drive on my string Ray Bike in the late 1960's .. I had not heard of a Modern 8 s;eed until a few days ago when I saw it on a belt drive electric bike ..
Do Purchase ! Had one of these for four years in Bristol UK and ridden up and down all the hills there, The bike was kept outside!! I conced shifter cable is tricky to connect.
Hi Dan. Excellent detailed video! How Shimano 8 speed hub can lose all the gears? (Alfine8 SG-S501) Do you (or anyone) has an idea what may have happened when with a loud bang hub lost all the gears and rewarded me with scrunching freewheeling pedals on every gear and a walk back home. Took the planetary assembly off the axle and didn’t found nothing wrong with the thing. And by looking it neither found a way how it even may lose the connection from the sprocket to hub in the first place. Then carefully looking the detailed explanation here neither found a way that could happen. At the end, just washed &oiled it and put it back together and everything works fine now. Has ran it with ATF oil for some 10 years now since it was new. Commuter bike driven broadly some 20 000km. When that happened, it was frosty -14C out and the bike hasn’t been wet previously just simply to frost up on me..
This reminds me of the class videos i had to study at Los Alamos National lab.... The PHD instructor would ask us if we got all that? We would shake our heads and say sure, good till next years refresher course!! John Cameron Swayze selling a Timex!! I just picked up a Specialized Globe Elite with this rig on it for $25.00 haven't got it home yet has flat tires.
Sturmey Archer never held any patent rights on epicyclic gearing, and if they did, it would be long expired, so there was no theft of intellectual property.
Let me save you 14 minutes of your life, the Shimano 8 speed hub is insanely complicated and unless you have a degree in mechanical engineering you will not understand a word this guy says during the entire video.
Really really Great explenation. So this is a 2 X 4 system. Where the first stage doubles the 4 Geras. While in a Rohloff the last stage doubles the 7 gears. ... Finally I understood :)
Great Explainations .. What are the friction losses in a planetary Hub compared to chains and sropecks.. What are the friction losses comparing chains to a cogged belt drive.. Seems as long as you use a planteray hub may as well use a belt drive..??
Excellent vid mate. How is it that you come to know all this? What I mean is, did you self teach what you know or are you a part of the design team for Shimano? Or what?
Dan, quick kudos and a question. First, thanks for the easy-to-follow explanation on the inner workings. I had my first negative experience on a 2nd-hand Alfine yesterday and was about to go balllistic on the guy who sold it to me, only to quickly realize that it was drastically out-of-adjustment. Now, a question: Assuming that the shifter-adjuster will only get me so much before it won't extend any more, can you add (or point me to) a video explaining how to replace or tighten the cable? Thanks again.
Hi James. There are tech documents on line showing proper cable instalation. They are somewhere buried on this page. si.shimano.com/#seriesList/26/74 However, I'll just throw out a few suggestions. First, ensure the cable is correctly routed around the cassette joint capstan. That is a very common error which will negatively affect shifting. Second, ensure the cable is free running in the housing. Tight bends should be avoided. Check the general condition of the cable for corrosion or fraying. If all that looks good, and you are able to line up the two yellow marks with the shifter in the 4th gear position, everything should work. Oh yeah, be sure you are using the correct shifter. The new models, the 7000 series have reversed the direction of spring pull and are now high normal. Make sure your hub and shifter are a match.
Thanks for the advice. My question was more "5 years from now, the cable will stretch to where I can no longer use the shifter's adjuster", but this is good detail on when I do have to replace it.