Crank drive goes Shimano Alfine 8

Allex

100 MW
Joined
Dec 5, 2011
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Location
Stockholm, Sweden
Yet another light and empty bike will be "destroyed", filled with heavy stuff like batteries and a motor :)
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At first it had to cope with this MAC 8T motor and HK lipos @ 37V20Ah.
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I wanted to try something new, so decision was made to run a Bafang BBS02 750W along with a hub gear at the rear, Shimano Alfine 8spd.
I wanted to remove ugly sprockets and also be able to choose a gear while not riding the bike. I know one person that had a good luck with his Alfine 8 and his Cyclone motor at 2kW, but this hub was one of the first models from Shimano, and we all know that companies strive to components lighter and therefore more bittle. It will be interesting to see if it is up to the job. I has been told that the new one, 11spd. with oil bath gear system will not take the stress of a ~1,3kW motor.

Found https://www.taylor-wheels.com/ in Europe, that had OK prices on a complete set with 26" rim, lace job and everything you need to mount Alfine:
26" 32 hole XM319 black rim with black spokes
Shimano Alfine 8sp 32 hole hub black for vertical dropouts
Sprocket, Shimano Alfine 18
Shift lever, Shimano ALFINE 8 speed black
Shimano Disc brake 160mm
Shimano Alfine chain tentioner

Total: 308Eur(344USD) with shipping
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This is what you need to install the whole thing, important to have those green/blue(one goes to the right, another to the left side) Non-Turn Washers to secure the Alfine Axle in the dropouts. The hub also uses Shimano c lock rotors, so you have to get that instead of a traditional 6-hole rotor.
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Yeap, SG-S501 is a lovely piece.
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Oh and we need a chain tentioner
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On the bike:
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Chainline with stock front chainring


With 18T at the back(you can shoose various sprockets from shimano) and 44T in the front I should be able to pedal up to 45-50km/h, according to this calculator:
http://www.gear-calculator.com/?GR=SNI8&KB=44&RZ=18&UF=2160&TF=90&SL=2.5&UN=KMH
 
This is a change of pace. Looking good. [THUMBS UP SIGN] Sounds like an awesome combination.
 
Thanks Brake!
What I also want to do is to remove the Battery bag and do a Kepler-style battery container so it looks more professional.
Like this:
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I will try this new config with 14s4p 18650 battery. I bought the cells from Tumich, Panasonic NCR18650PF 2900mAh
http://endless-sphere.com/forums/viewtopic.php?f=31&t=61608
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With 4p and 25A drain it will be around 2C per cell. Even if they are rated at 10A, I dont think you should be pushing them more than 6 Amps. When I did a discharge test the temperature at the end was 52°C

I cut away most of the weld on the end cap:
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And then ruffed up the tabs with Dremel, yes, I will solder them. This will make solder stick better. Wish I hade a spotwelder in my hands.
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Using hot glue to make a set of four:
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Ordered a sheet of Battery insulators, dont want to damage the plus side of the cans during solder.
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In the mean time I have been using this site:
http://epowerbikes.ru/constructor-en.php
To see how the battery placement would look like.
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Mounting the motor kit was a bit more complex compared to a regular hubmotor. I had to get new tools to remove old cranks and axle. Also a few new tools to secure the Bafang into place.
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Next problem was the chain line. I had it way of when I crewed on the chainring. Luckily this was an easy fix, mounting it the other way around gave me almost perfect chain line with Alfine 8!
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I did a short run with the bike, about 3km and was very pleased. The motor run very quiet and Alfine hub seemed to cope with the power well.
As soon as I get those insulators for my new 18650 I will start to solder up my battery and 14S 40A Li Ion BMS from Cellman:
 
I've racked up 2500km on my 36v BBS-2 (750w+ ballpark figure) and a Shimano Nexus7 IGH. So far so good (crosses fingers). 85% road 15% not road :wink: . An IGH that can handle the power ratings of a middie is such a good combination: no chain derailments, "semi" on the fly shifting (the nexus requires a depowering on the up shift), stronger chain options (i.e. single speed chains).

Looking forward to your results with the Alfine 8. I'm also thinking of changing out my rear deraileur system for an IGH. Was thinking of an Alfine11 but going to scrap that plan from your previous comments on its limited power rating. In reality, the 11 may be too much gear ratio for an assist bike (picture the lowest gear & 750-1000w of assist :lol: ) unless you really need to mule stuff around.

The one thing that doesn't tick with me is the trigger shifter on the Alfine but that's a personal preference. I like the feel of the twist shift as it feels "motorcyclish". Wondering if there is a twist shift option for the Alfines :?: If not, is it a pretty straightforward change to switch it out to twist shift via another model (nexus8) :?:
 
melodious said:
I've racked up 2500km on my 36v BBS-2 (750w+ ballpark figure) and a Shimano Nexus7 IGH. So far so good (crosses fingers). 85% road 15% not road :wink: . An IGH that can handle the power ratings of a middie is such a good combination: no chain derailments, "semi" on the fly shifting (the nexus requires a depowering on the up shift), stronger chain options (i.e. single speed chains).

Looking forward to your results with the Alfine 8. I'm also thinking of changing out my rear deraileur system for an IGH. Was thinking of an Alfine11 but going to scrap that plan from your previous comments on its limited power rating. In reality, the 11 may be too much gear ratio for an assist bike (picture the lowest gear & 750-1000w of assist :lol: ) unless you really need to mule stuff around.

The one thing that doesn't tick with me is the trigger shifter on the Alfine but that's a personal preference. I like the feel of the twist shift as it feels "motorcyclish". Wondering if there is a twist shift option for the Alfines :?: If not, is it a pretty straightforward change to switch it out to twist shift via another model (nexus8) :?:

I've read that the Alfine 11 is also significantly less reliable than the 8, in normal use.

Nexus and Alfine models can use the same shiters, and there is an 8-speed twist shifter option.
 
Yeah trigger shifter is not perfect. You actually need to click seven times before you get to that tall gear. Twist shift would be much faster. Let me know if this works out for you!

And I would prefer 3 spd, instead of 8-11.
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Would be so much easier.

Here is the chain line with the swapped chainring. It is actually as good as it could be. You can also see three spacers on the chain tentioner. They were included in the package for the adjustment of lower chain line.
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Allex said:
Yeah trigger shifter is not perfect. You actually need to click seven times before you get to that tall gear. Twist shift would be much faster.

A nice thing about trigger shifters is that when you want to shift up or down one gear, you can do it. Twist shifters (especially those for 8+ speeds) tend to shift two, three, or four gears when you just wanted one. And they're generally awful, and they preclude using good comfortable grips unless you cut the grips in half.

Top mount thumbshifters are best, in my opinion, but they are hard to get anymore. And there are none for gearhubs as far as I know.

And I would prefer 3 spd, instead of 8-11.
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Would be so much easier.

That's not only easier, it's a lot cheaper. I'd recommend the Shimano Nexus 3 with disc brake mount and 135mm spacing.
 
Question for Chalo: Should it be at all concerning that the 3-speed Shimano IGH only uses one non-turn washer, but the 8-speed uses two? I'm sure that one is fine for normal leg power, but what about when used with the mid-drive? (I plan to use a chain tensioner, so I'm not sure that I'd have enough axle length to add a non-turn washer as well, if it turns out that one is needed.) Thanks!
 
Avitt said:
Question for Chalo: Should it be at all concerning that the 3-speed Shimano IGH only uses one non-turn washer, but the 8-speed uses two? I'm sure that one is fine for normal leg power, but what about when used with the mid-drive?

The 7-, 8-, and 11-speed Nexus and Alfine hubs use two non-turn washers because they have a much larger ratio of reduction or overdrive than the 3-speed kind. The torque of the axle relative to the dropout is a function of input torque and the difference in ratio between input and output. SInce the 3-speed hub only steps up or down about a third, the torque at the axle will never be more than about a third as much as torque at the sprocket.

As for the addition of motor power through the gears of an internally geared hub-- I would not supplement with more than about 1000W for any gearhub other than a Rohloff or NuVinci. For a big guy like me, even that much extra could be a problem. If you really feel the need to put superhuman power through a gearhub, arrange to get that extra power by way of higher RPM instead of higher torque. That means using an extra-small wheel or placing the gearhub as a jackshaft rather than a hub.
 
Here is a Cyclone used with Adaptto mini-e and alfine 8, The guy has used this bike for over a year now(or maybe several years) it is more than 2kW of power on his config.

https://www.youtube.com/watch?v=ijimnucFyAU&t=168
 
I can only attest that I don't make 2kW of pedal power, but I have broken a stronger hub than the Alfine 8 with pedal power alone. If you use more RPMs and less torque than I make at the pedals, you might be able to get away with more power than what I suggest as a limit. But the only hubs explicitly rated for 2kW or more are Rohloff and NuVinci.
 
You might want to read the "Internal Gear Hubs" forum over on www.mtbr.com . There are no Ebike users in that forum, and the consensus over there is that IGH hubs are not suitable for off road use. They have not been able to come up with an IGH that does not break under off road use (even without the additional power input from a motor) except for possibly the Rohloff. I spent an hour or two reading that forum and changed my mind about building an ebike for trail use with an IGH since I didn't want to spend the money for a Rohloff.
 
Time for for melting the...err welding the cells :)
Got my 18650 battery Insulators, otherwise I could melt the plastic and make a battery short:
http://www.ebay.com/itm/24pcs-cardboard-4x-18650-battery-Insulators-Electrical-Insulating-Adhesive-Paper-/221470311726?ssPageName=ADME:L:OU:SG:3160
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I have a simple battery layout, so a zig zag pattern will be best here. Similar to this one:
http://endless-sphere.com/forums/viewtopic.php?f=6&t=27911&start=150#p890139

The current distribution across cells will be very even this way.
I is pretty time consuming to do a nice pattern for every group so I made a simple jig, this did speed up my work by a lot.
The wire is a 1,5mm solid copper and should be plenty for this amount of current.
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This is how it looks like. Not sure if I need to ad one more extra wire to the row of cells? The maximum current is around 25A. 1mm is ok for ~10A so at 1,5mm I probably should add one more...
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Next step is BMS and the wiring is very easy to understand by cellmans manual:
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And it works! I will make a few test runs before I go further with the battery enclosure. Got to make sure that this configuration is OK for this power level.
Did a 30km run today with no issues what so ever.

Now there is a few display versions floating around and this one seems to be the most advanced one 965 (not the same as 965A) it comes with a 5 button remote.
You can see the outside temperature and current wattage use from the display. It also looks like you can set a custom battery in the menu as well as make it go pretty fast. I was able to hit 56km/h today.
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Time will tell.
Like a said, I know a guy who used his alfine 8 for 10000km on a >2kW cyclone system without problems. If not I will go back to a regular system.
 
Thanks John!
The easy part is now finished. The hardest part will be fabricating a battery casing for this pack.
Here it is btw, I added one extra copper string on outgoing cells to keep the stress down on these two rows during peak currents.
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14S4P ~600Wh Capacity but in real world those cells will probably deliver 2,75Ah instead of 2,9Ah so recalculated:
2,75Ah*4p= 11Ah
14s*3,7V=51,8

51.8*11=569,8Wh
Wonder how many Km I could travel on this Bafang thing. But should at least be 40km

Here is the 2Hours(5A, 300W) charger from cellman, what is neat with this is that you have a 3 position switch to set output voltage to 58.8V, 57.4V and 53.2V. This enables charging to approx 100%, 90% and 50% SOC. Regularly charging to 90% SOC will help to extend cycle life. Charging to 50% is recommended for battery storage.
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Hi allex its crucial to get chainline perfect on these hubs any load thats not true will pull it apart,i looked at the last pic of chainline and it looks wonky. :D probably camera angle anyways.nice build so far.
 
I had an Alfine 8 on my 1st ebike :)
But I set it to a moderate torque, did not do wheelies like the guy on the video. Shimano hub gears are quite durable anyway. I tried a Sturmey-archer also on a normal bike and I broke a gear in that on my first ride, but I use the Alfine for several years.
You can mount the rear chainring inside out if you cut the plastic protector, then the chainline is ~47mm instead of 42. I did this and the chain never fell off, although I did not use a chain tensioner and my hub is an older version (SG-S500), not sure if it is possible with the newer one.
 
This is how it looks now. Not that sexy I know but that ugly bag really got to go.
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Oh and here is the guy with Alfine that has done 10000km on his cyclone over clocked to 3,5kW nominal power.
No problems what so ever on his hub.
[youtube]GUqtJUwKZ7A[/youtube]

Some old lipos sliced up...
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Time to work some more on the battery case. I really want to ditch my uglu battery bag. So I bought some aluminum and a cutting board :)
This will be A Kepler style battery holder
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3mm High density foam, similar to: http://www.ebay.com/itm/ESD-Antistatic-Anti-static-Anti-static-High-Density-Foam-150-x-150mm-1-3-5-10mm-/311113839700?ssPageName=ADME:L:OU:SG:3160
was used for shock absorbation
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The 1.5mm Aluminum I used was very thin, to get it more rigid a 3mm alu plate inside was used:


Cutting board was very easy to cut to the right shape. Now I need to make the wiring for the motor and find a place for the charge socket.
After this I will cover the box with some fake carbon film. More to come later...
 

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I have an Alfine 8 on my non-electric commuter bike. I have to say that this hub does not like shifting under any kind of load. When I shift while pedaling, about one out of every 10 shifts, it will not quite go into gear and then it; it will seem fine at first and then suddenly skip a tooth when you are not expecting it, which can be very annoying when it happens as you are trying to accelerate or take a hill. I pretty much have to stop pedaling completely when shifting to get clean shifts every time. Maybe I just got a dud, but that is my experience with the Alfine. So with an electric it seems like you would have to let off the throttle, stop pedaling, shift, resume pedaling and resume throttle. How has yours been working?
 
Yep that is the negative side of internal hubs like Alfine.
I during the PAS, it works very well to shift up until gear 6, after that I have to either stop pedaling or use throttle to interupt the pas, this will stop the motor for a few milliseconds and the gear jumps into place(I can do this while still pedaling). Same when I goe down in the gears. It feels more or less like shifting a motorbike without the clutch. Now after 300km I am used to it and don't even think about. But yes, it is annoying.
 
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