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Discussion Starter #1
I wrote a long post introducing this project, but it apparently never made it past the moderator review, so I'll give it one more go...

I have a 1964 Honda S600 that I have modified with a motorcycle engine (2007 CBR1000RR) and I am planning on adding an electric motor to make it a hybrid drive. I will be using a QWC/EVDrive EVD35 system running directly to the driveshaft after the motorcycle engine. It will be running at 96V with a Sevcon size 6. I haven't put much thought into the battery yet; I'm still working on packaging and engineering the motor and drivetrain connection. It should be a fun project and I'd like to hear feedback from some people who have more experience in this area than I do. Pictures and more info to follow, if this one makes it through.
 

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Alright, cool. :cool:

So the story goes like this: I have this motorcycle powered 1964 Honda S600 (seen here: https://www.youtube.com/watch?v=UsbfzmPCYX4) There are a few things I don't love about it, mainly that it doesn't have reverse, but also it could use a few extra horsepower and I'd like to re-do the driveshaft layout. It occurred to me that I could solve all of these problems by adding an electric motor to the powertrain. I've also been wanting to do an electric vehicle build for a while and this seems like a good introduction.

Because of the motorcycle engine location and packaging space, I'll be running the electric motor directly to the driveshaft and the motorcycle engine will be connected with a chain drive to a sprocket on the driveshaft. Max driveshaft RPM is 6500. I have a lot of fabrication and engineering experience, so I'm not worried about the mechanical side.

I'm not sure how much battery I'm going to need; I'm not looking for range so I suspect I will be getting the minimum battery size I need to output the peak 660 amps at 96 volts. Any thoughts on where I should be looking for high discharge current batteries? Used (cheaper) batteries would be preferable.

I'd also like to know if anyone has any experience with this layout: a hybrid setup with the electric motor after the transmission output. I suspect there are some requirements and, uh, nuances of this setup? Any other thoughts are appreciated.

 

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Hello -

DIY Hybrids are hard. There have been only a handful I know of that were completed, and those were of marginal success. Your best bet if you really want to do that is probably to swap the entire hybrid drivetrain out of another vehicle, for the s600 your best bet would probably be a first generation honda insight.

Going full electric in a small, light car like that however would work very well. You could probably easily get over 100 mile range with a fairly modest sized battery pack. Swapping in a leaf drivetrain would give way more power than the original setup and if you could find room for the entire battery (with that fastback design I bet you can) You'd have a ~24 (or 30) kwh battery in a car weighing well under 3000lbs.

good luck.
 

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He's right. Ditch the ICE. When I go back to work on ICE vehicles, for me, it's like going to the city park to look at the old steam locomotive on display there. It's part of a noisy, smelly, polluting, inefficient technology whose time has or is passing.

Of course, it's hard to argue against the romance of an old, familiar technologies. With the progressive shifting motorcycle transmission, you probably rarely use the clutch. In an EV, you could set up a mild regen to simulate ICE throttle response. Tie a faux shift lever/kill switch to a sound system that could simulate reving through the gears. Down-shifting would be more difficult to simulate. Or, you could just get use to the instant, no fuss delivery of a powerful electric drive. Watch the Tesla P100D videos or take a test drive.
 

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1. Nice to see you here! I am looking at your book on my shelf as I type this.

2. Car pics! An S600 is just about my dream car. I just nearly settled for an N600 a couple years ago. Where'd you find the S600? Cost?

3. Agreed with ditching the gas. Did Hybrid in '11 with TAMU. Integrating the systems well is really tough. Neglecting that, what kind of driveshaft RPM are you seeing? The EVD35 is...70ft-lbs peak? Seems a little weak. If you're wanting to fill in the bottom of the torque curve, the IMA motor isn't a bad choice. Around the same HP, MUCH more torque, and will spin to well over 6000rpm. It has been awhile since I've looked at the chart, but I believe the base speed on 150V is around 3500rpm. Downside is that it is a pancake motor, so thin but larger diameter and you'd have to make end plates for the housing. A size 6 would drive it nicely, though. You could also look at any of the Toyota HSG motors. Again, would have to make the housing, but they are far more torque-dense and are stupid cheap. Neither of those options is plug and play. You'd have to characterize the motor, which is pretty difficult with a Sevcon.
 

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Discussion Starter #6
I'm not going to ditch the motorcycle engine; I like it too much! I have no doubt that full electric is better than a hybrid, but for this project, I'm going with a hybrid. The goal is really to add a bit of boost power on top of the ICE, and also add reverse. I'll probably attach the throttle pot to only have the EMotor come in at >50% throttle.

I can't seem to add comments to this thread that have pictures or links without it going to a "moderator review" which never gets reviewed, so sadly, you'll have to use your imagination, or Google, to find videos and pictures of my "Hot Rod Honda S600"

The packaging space I have for the motor is tight, so an IMS won't fit. the EVD35/DLC28 pretty much maxes out my space.

After digging around for battery information, it seems my best bet will be 1/4 of a Volt battery (2 48v modules in series) which will give me a 24s with about 4kWh and enough discharge current to give me short (<10s) bursts of 660 amps. I can't seem to find any reason that a Turnigy TQ4 4x6S hobby charger won't work for me since the battery will be small and since it will also be able to drive on gas alone (in other words, slow charge should still fill an empty battery overnight and I don't foresee being stuck anywhere with an empty battery.)

Actually, that brings up a good question: if I'm not using the motor (PMAC) as a power source, but I am spinning it with the ICE, will it generate electricity whether I want it to or not?

Anyway, I appreciate the comments and concerns. Please keep them coming!
 

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I can't seem to add comments to this thread that have pictures or links without it going to a "moderator review" which never gets reviewed, so sadly, you'll have to use your imagination, or Google, to find videos and pictures of my "Hot Rod Honda S600"
Is your S600 the one featured by Jay Leno? Impressive!

Assuming that this is the car, obviously original authenticity went out the window long ago (e.g. the entire original rear axle and suspension are gone, replaced by BMW, Miata, and custom bits), so you might as well do whatever makes the car even more fun for you. :)
 

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Actually, that brings up a good question: if I'm not using the motor (PMAC) as a power source, but I am spinning it with the ICE, will it generate electricity whether I want it to or not?
No, it will only generate when the controller forces it to. You can motor, generate, or do nothing... at any speed. Watch the controller settings: some can be set to regeneratively brake when the "throttle" input is zero, instead of just freewheeling, and you likely don't want that.
 

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I have no doubt that full electric is better than a hybrid, but for this project, I'm going with a hybrid. The goal is really to add a bit of boost power on top of the ICE, and also add reverse.
A parallel hybrid is an interesting combination with a motorcycle transmission, because it can provide an electrically-powered reverse. Unfortunately, the combination also makes it difficult to incorporate a motor sandwiched between the engine and transmission, and if the motor were coupled to the engine's crankshaft then you wouldn't be able to use the motor for reverse.

Does the car have no reverse now?

I'll probably attach the throttle pot to only have the EMotor come in at >50% throttle.
If you're up for a more sophisticated solution, it would be nice to more smoothly extend the engine's power, rather than just add on like the nitrous. Perhaps you could program motor torque to "top up" the engine torque to a relatively constant level (proportioned to throttle input), across a wide speed range. That would mean it would be used at engine speeds below the torque peak as well as above, extending the effective power band.

To regain battery charge, all the usual hybrid techniques apply: regenerative braking; and sustaining more engine throttle than requested by the pedal, while using the excess power to generate.

Most hybrids are configured to minimize fuel consumption while otherwise maintaining a typical gas-only driving experience. In this case, the target can be complementing the gas engine performance with electric motor performance.
 

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Discussion Starter #10
Is your S600 the one featured by Jay Leno? Impressive!
Yep, that's me!

There isn't a whole lot of space for the motor, but It should fit neatly where the original transmission was (I'm using the integrated motorcycle transmission). If I mount the EMotor on a frame just behind the MC engine, and have the driveshaft mounted directly to the Emotor, I should be able to run a short shaft to a sprocket and get the MC engine power to the driveshaft through a chain. Not ideal because I'm using the chain on the more powerful engine which will give me more total parasitic losses than if I did it the other way around, but otherwise this seems to be an effective and reasonably priced approach that mostly can use OTS industrial components (keyed shafts, sprockets, etc).

 

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Have you done any combined tractive force plots to see where you're traction-limited? It doesn't make sense to fill in the bottom of the torque curve if you're already traction limited, unless you're using it to remove a shift or two. Maybe go from using 1st (do you use first now?) to start rolling to 3rd?

Thinking more, my approach would probably be to gear it to maximize usable tractive force. That might actually be further up the rpm range. I know the Sevcon is pretty flexible, but I wonder if you can apply torque limits based on RPM. It would be slick to pick a maximum torque (for peak grip on your best surface or slightly over?) so the controller only starts out at say 30% torque, then ramps to 100% as the rpms climb. That would get tricky with shifting, but at least logging the gear is easy with a sequential.
 

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I have tractive force curves from when I originally set up the MC engine gearing, but I don't have the tires characterized, so it doesn't help too much. I have pretty sticky tires so there's still a lot of traction there; I'd like to just max out power on both motors and see what happens, then go from there.

I've done all my mechanical design for motor mounting and power transmission and I think I'm happy with it. It's all packed tightly into the transmission tunnel.



I decided to go with two Chevy Volt modules; they are inexpensive and have a high discharge rate so I can get away with the high amps without having too much battery. They showed up today, so now I need to build an enclosure with a cooling loop. Still need to look into contractors and wiring, I haven't done any research on that.
 
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