6X10 Mid Drive Trike

Set up sort of like a Stoke Monkey, I don't know where this thread fits.

Anyway, I purchased this motor when Jason put them on sale a month or so ago. It had a screw on disk brake adapter, so I just turned the motor around and put a standard 16 tooth freewheel on it. The motor support/torque arms are made from 1/4" x 1" steel. The front ones are attached where the seat is normally bolted on, and the rear ones are attached where some chain idlers were bolted on. For the last week I've just been waiting for the 180mm M8 stainless steel bolts to come. Couldn't find any 7" long 5/16" or M8 bolts locally and didn't feel like driving 100 miles or more to try to find them. UPS delivered them today from "Bolt Depot" in Mass.

No fabrication work was required on the trike frame, but I did raise the seat about 4" using some 1/4" X 1" aluminum stock that I had. I like a fairly upright position, and with the longest boom Terra Trike makes for the Path the crank relative to the seat was higher than I liked. The seat is still lower than Terra Trikes new Rover model.

The rain stopped long enough for a short ride today. This trike has the Nexus 8-speed. Didn't go where I could check out top speed in 8th gear, but did exceed 15 MPH. In low gear up the 20% grade part of the driveway it maintained 5 MPH without a groan. Coming up the road from town in 4th gear it maintained 8 or 9 MPH through the 15% grade. This is running at 48V and a max current of 23 Amps.

Will the Nexus last? I don't know, but hopefully it will. I always thought I would put a freewheel crank on this type of setup, but after reading the Stoke Monkey info I've decided to give it a good try without the extra freewheel on the crank. What this means is whenever the motor is running the pedals have to be turning.

Edit, added picture on 7/14/10 to show added brace.

Edit: Removed pictures that were not displaying and added an old picture that shows the chainline. Also just a note, but the trike now has a freewheel on the crank.

Edit: This trike was changed back to a pedal trike with the original Nexus8 in 2017 and sold. The 9C motor and Nuvinci auto shift transmission have also been sold.

That is thinking outside the hub box That should keep that motor really happy running it through the gears. We finally got some sun here in Kansas. Usually we get a lot but it has been really green here the last 3 years. I am from western Washington so it really doesn't bother me but it is weird for the midwest. Keep the reports coming. This is a nice / new application.

Show us the other side to see the mounting.

nice work
i'm looking forward to hearing more on this setup

Thanks for the comments. I was able to take another ride between showers this morning. On a nice straight stretch I pushed up to 21 MPH in high gear, but the cadence was out of my comfort zone even with the motor doing all the work.

I tried the hill heading home in 5th gear, but it bogged down below what I had maintained in 4th yesterday. So I shifted down to 3rd and easily maintained 8 MPH up the 15% grade.

Torker, there's not much to see on the left side. The factory seat bolts go right through the center of the main tube and the support for the rear idler was factory welded under the main tube. I removed the nut and washer on the motor axle, but being all black it's still hard to see how the supports are also filed out to fit the axle flats, so the supports double as torque arms, giving 4 times 1/4", or one full inch of torque arm thickness.

Good job Rassy. It looks like the motor is trying to twist in the holes, so get some kind of nice thick torque arm(s) on the axle flat(s) before it spins out on you and breaks the wiring harness, which is a pain to replace and often blows the controller in the process.

John

Thanks for the observation John, but the "ovals" were not filed in straight (relative to the lengthwise direction), with the support arms. The flats on the axle fit the flats inside the ovals very precisely and there is no twisting taking place. Each support is 1/4" thick, so to spin out the axle would have to cut circles in a full inch of steel, and since the ovals are all closed, unlike regular dropouts, no spreading can take place.

Excellent. 1/2" of steel on each side is what I've been running for over a year at fairly high power, so you're good to go. I may even "borrow" your wrap around chain approach to prevent a freewheel from unscrewing.

I liked the Stoke-Monkey as soon as I saw it, but the price is outside my budget at this time (I have no experience with the SM, but I'm sure its a high-quality product from the builds I've seen). I'm glad to hear this works without a lot of adaptation and fabrication work.

I would like to do this exact thing with the Amped-Bikes geared hub. The geared hub would be smaller in diameter, but perhaps louder. Yours is bigger and heavier, but most likely near silent and cheaper too.

You can source a larger-diameter freewheel if you want a higher electric top-speed...the non-hub resources sticky has chainring links to get the best prices on larger chainrings (such as a Vuelta 52-tooth) so you can still add pedal power at the top electric speed.

http://endless-sphere.com/forums/viewtopic.php?f=28&t=11690#p178009

I like this--it's a lot like how I want to run one on the cargo bike in progress. Yours is cleaner than mine.

Awesome new application for this motor. I want to see a video of that big 9C spinning away Got me thinking of a midrive for my rear susp. EZRider.

I've gotten used to this setup now and I really love riding it. Most of the time I've just left the bike or trike in it's top gear when using hub motors, except on hills which have always been a problem, both near home and on longer rides elsewhere.

But... got a break in the rain yesterday and took a 24 mile ride. About a mile into the ride 5th gear got noisy and soon just spun out. I figured the Nexus was toast but the other gears seemed to be fine. Then at about mile 15 7th and 8th gears both starting skipping and making noise. Turned out the Nexus had just gotten out of adjustment and with a little research I learned how to properly adjust it and everything seems fine now. Probably didn't help it any to get so far out of adjustment.

But... On my ride to check out the Nexus something started knocking in the motor area. Stopped twice and couldn't find any problems. So today I started out on another ride, and even though everything was running smoothly, the knocking was getting worse, so I returned home. Coming up my hill it sounded like an old Ford with a bad connecting rod. Turned out to be the new Shimano freewheel on the motor. Just 30 miles and it is gone. Actually was still working okay, but has so much slop it flops from side to side under load and the knock was the metal to metal strike as it flopped.

Had read about freewheel problems, but thought it applied to the higher power rigs, plus I am working hard not to over stress the Nexus by starting up in lower gears, always pedaling first, and bringing the motor up to speed slowly. Quick research seems to indicate that the ENO BMX single speed freewheels just fit 1/8" chain and my tripple length chain is 3/32".

I have a 14T track cog and a bottom bracket lock ring that I'm going to try for the time being. Hopefully with a little blue Loktite on the lock ring the cog will stay on. There won't be much pressure trying to unscrew it, but the whole motor will turn when just pedaling, which will be trying to unscrew the cog. The cog teeth are closer to the motor and there's not enough threads to add any spacers, so I'll have to redo other spacers to keep the chain alligned. Should get this tested tomorrow.

This will probablly be just a temporary fix because I like to pedal without the motor and expect the lack of a freewheel on the motor will be noticed, depending on the cogging effect. Going to the EPower Challenge at PIR in Portland this coming weekend, so when I get out to civilization might be able to find a good freewheel at a regular bike shop instead of taking pot luck again on-line.

A post like this makes me have second thoughts on my mostly FWD recumbent fleet. No mid drives for me! :wink: I did start this weekend on a front cute 85 through the gears for one my bents hopefully it'll plug in as nicely as yours looks. Wish mine came with a spin on disc mount to save me some welding time I'm driving the left side so no unscrewing problems for me though. Not too excited to hear about your freewheel since I have the same exact one! ugh.

Do you know how much power you are throwing at it? 1" seems like an awful lot of steel just wondering a thickness/power ratio. The stoke monkey doesn't look like it has even 1/2" overall and has open ends on the mounting holes but perhaps the pedal before engaging really takes alot of the torque off or maybe I'm not seeing the scale right on the stokemonkey pics. I'd rather find out before then on the road that I didn't give the motor enough respect for torque.

How does it pedal without the power on with the wrap around pulley system? Probably just looks like it would be an issue since if I remember correctly the rears on the flevo tandems have quite a lot of pulleys and no one ever questioned those.

Rassy said:

Quick research seems to indicate that the ENO BMX single speed freewheels just fit 1/8" chain and my tripple length chain is 3/32".

Click to expand...

If you like, you could file down the teeth on the ENO to fit the chain. It'd be a bit of work, but since the important part you're after is the bearing and internal mechanisms, it might be worth it.

Hi,

Good work!

Rassy said:

I always thought I would put a freewheel crank on this type of setup, but after reading the Stoke Monkey info I've decided to give it a good try without the extra freewheel on the crank. What this means is whenever the motor is running the pedals have to be turning.

Click to expand...

Another option would be adding a FW sprocket to the hub motor shaft and running two chains.

Like this:


or this:

Put the track cog on the motor this morning, along with a lock ring so that it won't simply unscrew when pedaling without running the motor. It only has to be tight enough to spin the non-running motor as the chain is pulled during pedal only. When using the motor it works just like a freewheel and the motor tries to thread it on tighter.

Anyway, went for a 25 mile ride and everything worked great. No shifting problems with the Nexus. In some ways I like the non-freewheel better because the pedals bring the whole motor up to speed before hitting the throttle, so the motor always engages smoothly with the Nexus. But when pedaling only, there is a little more drag, although no more than if the motor was installed directly in a wheel.

In the longrun I'll probably get an ENO freewheel, and if necessary go back to a 1/8" chain. Thats a long story, but the trike came originally with a 1/8" chain, which I no longer have and was used on another project for my son. But with the freewheel I'll be able to conserve battery on 50 mile plus rides.

evblazer, I may have used more steel then necessary, but I always overbuild things when I can. Plus, commercial stuff can be made out of harder material and heat treated, etc., things I don't have a clue about and not that interested in. Also, as far as the extra idlers on the chain, etc. I don't think it adds too much. Sort of like the routing around a derailuer on a regular bike. I used all large idlers with neopreme beds on the power side so they run smooth and quiet.

Ah very true those stoke monkey mounts look pretty fancy so might be some good tool hardened stuff or something. I tried drilling out an old shimano bb cup from the flat side and pretty much got no where on it but the steel I have to make my mount on is like butter.
I have some 1/4" x 2" flat stuff laying about so maybe I'll try making the "dropout" section out of that at least maybe even use a pinch bolt and such. Just reread that dropout failure expiriment thread and yeah no thin stuff 1/4 inch is good.

I wonder if someone was to have a traditional cassette and a triple up front if they'd have an issue with the drive being where it is. Would too much chain slack cause issues if the motor overpowered the pedaling or if someone slacked off pedaling so built up the slack chain between the drive and the pedals causing a dropped/jammed chain. It wouldn't happen in your setup I'm thinking since you have the IGH and Single up front just was thinking about it last night when looking at my bikes and seeing if I could copy your setup. I think an IGH would definately be very helpful on driving the chainside hm.

EV you're right about the IGH when driving the right side. I think you would encounter chain issues if trying to do what I did on a deraileur rig. I had this type of drive in mind when I purchased this trike last year.

For chain slack building up between the drive and the pedals being a problem there could be a tensioner on one of the idlers in that area, or a freewheel on the crank. So far I have not had any chain issues, but will probably install a freewheel crank someday so I can take short breaks from pedaling on long rides, or want to go above my comfortable cadence for a while. I know my son has a crank with 56 teeth that he's not using. I'm going to borrow it for a test next time I see him. The stock crank on the trike has 46 teeth. This would drop a cadence of 100 RPM to about 82 RPM. One issue, it has 150mm crank arms and at about 6' 1" with long legs I've never used anything but 170mm cranks. Also if the gearing is modified too much, pedaling home when the battery dies or some other problem can be difficult.

But my hill is too steep for me anyway, and I have had to push every rig I've had up it at least once, including this trike with a trailer. That's why I have electric assist in the first place.

Rassy said:

Coming up my hill it sounded like an old Ford with a bad connecting rod. Turned out to be the new Shimano freewheel on the motor. Just 30 miles and it is gone. Actually was still working okay, but has so much slop it flops from side to side under load and the knock was the metal to metal strike as it flopped.

Click to expand...

With Stokemonkey, Shimano freewheels fail at a rate of about 25% a year used hard on a daily or near-daily basis. Not sure why yours died so fast. Unlucky? Anyway, ENO freewheels are 3/32" and hold up. I don't care for their loud freewheeling noise though (not an issue in your case).

"...It had a screw on disk brake adapter, so I just turned the motor around and put a standard 16 tooth freewheel on it...."

Would you happen to have any idea of any other hub-motors that have the screw-on disk brake flange?, I'm curious as to the other hub-motor options that might work using this configuration.

I think you could use any rear hub motor that has the ability to attach a freewheel, usually with a 1.375 inch thread. You just have to run the motor in reverse. The reason he used the brake side was to keep from having to reverse the motor.

Dave

dbaker is right, I used it because it was there, however, I am unsure if all motors will run properly in reverse due to the placement of the sensors. I think you can also switch the covers around so the freewheel mount is on the "wrong" side. I don't know what other motors might have, it was a suprise to me that these had the screw on disk brake adapter. Plan A was to run the motor backwards, and plan B was to use a track cog and wrap the chain around the other way. Locking the track cog on so it wouldn't unscrew would have been a challenge.

Been gone for a week, and also attended the E-Power races at Portland International Airport. Could only think how Matt's trike would have dominated those races with enough battery power.

Cool build. Video?

tfahrner wrote:

Anyway, ENO freewheels are 3/32" and hold up. I don't care for their loud freewheeling noise though (not an issue in your case).

Click to expand...

Thanks, I found on their site where they are 3/32" and have one on order from "Bikeman". I knew they would be noisy because of my Grandson's BMX experiences. The problem is, my non-motorized bike buddies will soon figure out if they can't hear the freewheel I must be using the motor, i.e. cheating.

The ENOs are relatively loud but it's a high quality noise It's possible to weaken the pawl springs a bit, to make them quieter....

These freewheels were delivered yesterday, along with the cranks and 48T chainwheel. Too bad I'm taking off in the morning on a fishing trip, so it will be at least a week until I can install them. Plus, I have a crank removal tool on order that I need to remove the old cranks.

After riding over 100 miles without the freewheel cranks I am sure they will improve the experience, in spite of what Stoke Monkey guys say on the subject. On every ride I have done something to make the motor jerk on the cranks, such as deciding to adjust myself on the seat a bit and just stopping pedaling without letting up on the throttle. On the other hand, since I prefer to pedal all the time I don't think the freewheeling cranks will keep me from being in sync with the motor most of the time.

So I hope to report back in a week or two how these work out. The freewheel will allow me to check out the WOT speeds and current draw in each gear. I have a WattsUp set up with long wires that allows me to temporarily tie it to the bottle cage so I can peek at the amps draw while riding.