Stokemonkey returns with freewheeling, from ebikes.ca

spinningmagnets

spinningmagnets

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The Stokemonkey stumbled along for a while. I think it was because it required the pedals to spin while powered (leading to the pedals to strike the ground in a banking turn, or pedals striking your leg).

Either way, they were out of production for a while (the official rumor was supply chain issues), but...the good news is: the stokemonkey is back, and...now it freewheels! and it is available from reliable vendor ebikes.ca (based in Western Canada). It has two configurations available, one of which uses a double freewheeling chainring set on the right side, to give the motor the use of the bikes gears (YES!). The motor is a near-silent 408 clone with improvements, and you can chose from an 8-turn or a 9-turn.

What's interesting about the history of this product, is that the Stokemonkey was the reason Yuba incorporated an uncluttered mid-drive space in the latest version of the Mundo, but when the newest Mundo version became available, the Stokemonkey suspended sales of their drive. Now, both are available.

"Factory longtail cargobikes" (5 pages)
http://endless-sphere.com/forums/viewtopic.php?f=3&t=32220

http://www.ebike.ca/store/store_stokemonkey.php
Here's a pic of the old Stokemonkey:
StokeOnYuba.jpg
 
The Stokemonkey is an awesome motor. Very hackable. I fitted one onto a two-wheel recumbent, now my buddy has refitted it to his trike recumbent. Mid-drive has a big advantage in efficiency at low speeds, because your motor still spins at high speeds. His Stokemonkey'ed bike kills my direct hub drive on watt-hours per mile side-by-side, by up to 50% depending on terrain.

Of course, there are limits to how much power a bike drive train will handle. The Stokemonkey is within those limits running about 750 watts, or about 1.5 Lance Armstrongs. Good 25 MPH E-Bike. If you want a >1500 watt motor, then a mid-drive will probably just break your chains.

If you are considering any kind of mid-drive, use a Stokemonkey as your starting point. Since it is a bolt-on drive, the addition of a stock Stokemonkey to a stock long-tail bike makes a great beginning E-Bike project, you'll have it running in an hour or two after the UPS truck arrives. Yet it's versatile and reliable enough for a serious E-Bike Commuter.
 
When are they going to start offering a left side drive ?

Been waiting for their web site to update. Seen they updated today for November , but still no sales of left crank drive thru the stoke.

Really tempted to get one of these to save some weight on my yuba.

Id hope you could pump more then 1500 watts thru tht baby tho ? I was hoping 2k with 2500-3 for short durations.
 
They ARE offering the left side drive now. The parts work for either side. For left side, you need to order the stoker crank. For right side, you need to order the idler that wraps the chain around the freewheel from the bottom. If you don't want to pedal, you have to order the freewheeling right crank.
 
I think the SM has always had a freewheel on the motor hasn't it? I'm guessing that Spinningmagnet's reference to 'freewheeling' may relate to the f/wheeling crank now used in the anticipated right-sided drive configuration. The original left-sided use of the drive (driven chain feeding left-side tandem chain wheel) remains the same as far as I can see. The standard freewheel employed on the motor seems to only be operational in pedal-only mode (so you're not forced to turn against motor resistance). Otherwise, my understanding is that the 'enforced' pedalling under power (perhaps 'enforced' is too strong a word) remains a distinctive feature. I'm very interested in the original SM outfit as a drive for a long-tail bike I have that was made back in the early '80s. Being built to suit a narrow drive train and rubber, there's not much room for other mid-drive configurations nor for the 135mm OLD of most hub drives. The Stoke Monkey however has an impressive degree of flexibility...
Savvas.
 
Hi,

http://www.ebike.ca/store/store_stokemonkey.php
Classic vs. Right Side Drive
The classic Stokemonkey design uses a modified rear hub motor with the freewheel on the left side to turn a tandem crankset. This arrangement is elegant and simple, and if the motor RPM is adjusted to match the rider's cadence then as the rider changes through the gears the motor too would be optimally geared for the wheel. However, it suffers a perceived setback that the motor forced the pedals to turn, which for the unacquainted can be disconcerting.

In our new right side drive configuration, there is only a single chain on the right for both the pedal and motor system. The use of a Patterson 2-speed freewheeling crankset allows the motor to drive the chain without spinning the pedals. Furthermore, by clever use of the chain angles and idler pulley locations, we are able to sense the rider's pedal torque on the mounting bracket and provide proportional torque assistance via the V3 Cycle Analyst. Pioneered by the likes of BionX, this is widely seen as the gold standard for intuitive human/ebike control interface.

While the classic configuration can fit on a wide range of cargo bikes, the right side drive option requires a custom machined clampset particular for each type of frame. We are in the development process to bring RSD Stokemonkey kits for the Xtracycle Edgerunner and Yuba Mundo platforms, but do not expect full release until winter 2013.
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"perceived setback - disconcerting"?

Scary and unsafe are more accurate.
 
"Scary and unsafe are more accurate."

Apparently many of you have never ridden a tandem bicycle. My wife and I, like everyone else in our tandem club, rode our tandem for over a decade without difficulty, and the Stokemonkey-style drive is even safer, since the captain is in direct control of the "stoker". A properly set up Stokemonkey-style drive will never spin faster than you want to pedal, and only when you want it.
 
or a tricycle. or a fixed gear bike of any sort. all same idea. at high power the stokemonkey woukd be scary, but its not designed for that.

I prefer the idea of the freewheeling crank, but don't think the direct is that dangerous.
 
Well, I'm curious if this new ebike.ca Stokemonkey system will fit older Yuba Mundos?
Attached is a picture of a Version 2 Mundo. The motor would have to go forward of the seatpost tube, unlike the Version 4.
I was tempted to go with the GNG until this news....
Added a picture of a Mundo Version 4 for comparison.
 

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Hi there,
I've just completed an install of a classic version of the Stokemonkey on my CETMA cargo bike. It's much fun. I've written up documentation for the install process in my blog: http://bostonbiking.blogspot.com/2013/12/stokemonkey-kit-installation-classic.html?spref=fb

I didn't provide much info on the CA, as I'd only config'd it quick and dirty. Hopefully, once I learn more about it and fine tune it's config, I'll be able to post a better CA config.

I've lurked on this thread for a long time and have learned a lot from you all; thanks!
 
Warren said:
"Scary and unsafe are more accurate."

Apparently many of you have never ridden a tandem bicycle. My wife and I, like everyone else in our tandem club, rode our tandem for over a decade without difficulty, and the Stokemonkey-style drive is even safer, since the captain is in direct control of the "stoker". A properly set up Stokemonkey-style drive will never spin faster than you want to pedal, and only when you want it.
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amberwolf said:
fechter said:
mr.electric said:
I always wondered how it would be riding without a freewheel like the stoke monkey.
Click to expand...

Seems like it would be pretty easy to get hurt.
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I had some pants get shredded, trapping my leg to the cranks, preventing me from even proceeding down the road at all (in traffic!) while I had this type of setup on CrazyBike2. Mine was slightly different in that the pedal cranks *and* the motor both went to a jackshaft that went ot the regular drivetrain, but there was no freewheel, and if the motor was running the cranks were spinning, too, and vice-versa.

Because of the reduction gearbox on it, and the great deal of loading that put on the system in reverse, I could not move the cranks backwards to unwind the pants from the chain/chainwheel, without backing up the bike.

I don't rmemeber where they are documented on my old Electricle blog, but there should be at least two posts about this, one I think I had pics of my pants.

Once was jeans, and tehy were so tough they didn't just shred, the seam was caught and it began to pull my leg around and me off the seat before I could let go the throttle. I was in the righthand lane of a 40MPH main street with cars behind me and HAD to suddenly stop, almost run over by the car right behind me, and constantly harrassed by drivers honking and zipping by roaring their engines becuaes I was partly blocking the rightnand (of 3) lanes. Another smaller car was stuck behind me while others went around him and me, but he was so close I could not back up at all to get loose, and he probably couldn't back up with cars behind him, either. I had to climb out fo the seat sideways and sort of partly upside down in a really awkward fashion to try to cause the jeans to rip enough to let my leg loose enough for me to get it past the crank/pedal enough to let the trapped pant leg pass around the chainweel and out of the teeth, without breaking my leg in the process. (extremly high-torque powerchair motor setup). Then I could tuck the ruined pants into the sock and get going off the road onto side street to deal with teh damage.

The other time I remember for sure was pulling into a left turn lane on dunlap on the way to work, and my black workpants caught the same way--but they tore, so I was more easily able to free my leg and get off the road into a parking lot.

Simply ensuring my pants were always tied tight to my leg instead of any folds loose to catch, and/or a good chainguard, would have prevented the issue, but it does show that it could indeed be dangerous, depending on circumstances and rider stupidity and unpreparedness levels. :lol: :oops:
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Hi Warren,
Warren said:
Mitch,

We get your point. Don't ride a bike without freewheeling cranks. It can eat your pants, if you give no thought to proper riding attire.

12,001 miles, so far. Hasn't eaten my pants yet. :)
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Deliberately distorting my point, while implying it's a foolish point of view. That's not generally considered acceptable on this forum.

But beyond etiquette I don't understand why you would enjoy doing that. I think that it feels good to praise people and it doesn't feel very good to be deliberately unkind.

But if it makes you feel better to imply that I'm an idiot or even to call me an idiot you have my permission to continue doing that.
 
I haven't found anything indicating if/when the freewheeling SM will fit/work well on a Big Dummy. Any updates appreciated.
 
I am also interested in a right-side freewheeling version of the stokemonkey for my Surly Big Dummy.
 
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