DIY Electric Car Forums banner

Red's Electric Motorcycle

40K views 66 replies 12 participants last post by  vaporer 
#1 · (Edited)
Hello everyone,
I am in the planning/design stages of an electric motorcycle build and about a month till the donor is mine so I decided it was a good time to get some guru input.

Intent: Performance Street/Race Build. As much performance as I can get @ 30–50mi per charge.

Donor: 2003 Kawasaki ZX-6R This is my donor because it’s free! But it has upgraded to ohlins forks and suspension so it works out except I have to plan a brake upgrade.

Motor: DLC-28 PMAC, 50-60hp@16kg with a 6500rpm cap. I can run it safely at 120vdc-132vdc, it’s got one of the best pwr/wht ratios for the price range, and its liquid cooled PMAC for when I start doing dumb things.

Controller: Sevcon Gen 4 Size 6 or Soliton Jr maybe? All the bigger stuff seems like overkill. Comments? Suggestions?

Cooling: Admittedly, I haven’t done as much research on this as I probably should have. For now I’m going to keep the radiator in its original place, but I’d like to find a thinner/lighter one and utilize more of the body “mouth” (and maybe some type heatsink/intercooler for an electronics chilling plate). After that it comes down to plumbing, connectors, and a few 30 GPH+ pumps. Thanks Amazon.com!

Gears/Chain: I assume some online place that can make custom 1000cc+ strength sprocket/chain kits. But truthfully I don’t know much about torque vs chain strength or what sprocket sizes I’ll need. But it looks like I’ll need at least a 13 or 14 tooth to clear the swingarm. And my crappy google calc says a 1:3 ratio gets me around 185kph at 80% motor rpm so that’s my starting point..

Batteries: A123 Prismatic pouches (google “AMP20M1HD-A”) for the density/volume. I’m thinking either 38s (121.6vdc) or 41s (131.2vdc). I think I can squeeze about 150 cells (or more) in but I have to figure out the rest of the components first.

BMS: No clue! I probably should with the size of the investment.. Please help!

Suspension/Wheels/Tires: Stock for the foreseeable future.

Charger: Um, later..

Miscellaneous: Not really sure about contactors, converters, and fuses. Seems to be only a few everyone uses and less that will work for this type build..

So um yeah.. Plus I still have to name it! :D
 
See less See more
#2 ·
The Soliton is a DC controller for a series wound or PM motor, so unfortunately you're pretty much stuck with Sevcon. I wouldn't bother with any other controller, as these controllers must be (sometimes painstakenly) tuned to the motor they drive.

The DLC-28 is a good motor/controller combo. Usually the controller seller should include a contactor that works with it. I like the LEV200 contactors for Sevcon and Curtis applications. A little more than normal, but sealed and a good fit for motorcycles.

1:3 ratio is a bit too low IMHO. Something 1:4 t0 1:5 or so is a better choice for this motor. If its too low, you'll suck amps for low RPM/road speed and it will kill acceleration and range.

Good size chassis, you'll need 5-6kwh of energy onboard to get a good performing bike with ~30-50mi range.

Where are you getting Genuin A123 pouch cells? Be very careful, some are knockoffs, some haf cut tabs. Pouch cells take a lot of work to get them all hooked up, so just be aware. Alternatives that will work well are CALB cells, something like 100Ah or so.

Two names that I've worked with for BMS are Elithion and Orion. The first is distributed (one board on each cell-group) and the latter is a central BMS (one wire to each cell from a centrail unit). Both are nice setups and have similar parameters and programmability and options.

Check out elmoto.net too, all motorcycle guys.
 
#3 · (Edited)
Thanks for the info!

1:3 ratio is a bit too low IMHO. Something 1:4 to 1:5 or so is a better choice for this motor. If its too low, you'll suck amps for low RPM/road speed and it will kill acceleration and range.
If I put the motor motor directly in-fornt of the the swing arm, and need almost a 3" gear to clear it, the rear sprocket is huge! How are you guys overcoming this? I assume most move the motor and use a gear between the two (like a belt belt type torque converter)?

Where are you getting Genuine A123 pouch cells? Be very careful, some are knockoffs, some haf cut tabs. Pouch cells take a lot of work to get them all hooked up, so just be aware. Alternatives that will work well are CALB cells, something like 100Ah or so.
Wow, lots of knockoffs.. Any ideas on sourcing these cells?
 
#4 ·
Thanks for the info!



If I put the motor motor directly in-fornt of the the swing arm, and need almost a 3" gear to clear it, the rear sprocket is huge! How are you guys overcoming this? I assume most move the motor and use a gear between the two (like a belt belt type torque converter)?
Most I've seen use just a sprocket on the motor, long chain and a large rear sprocket. It's not actually that bad, just make sure it clears the swingarm. I used 530 chain because its easy to find a front sprocket for (ANSI #50 sprocket from surpluscenter.com). Sprocketspecialists.com has rear sprockets.

Here's mine, showing front and rear sprockets:
http://www.evfr.net/coppermine/albums/5-14-11/normal_Picture_007.jpg
http://www.evfr.net/coppermine/albums/7-18-10/normal_Picture_013.jpg
http://www.evfr.net/coppermine/albums/5-14-11/normal_Picture_006.jpg




Wow, lots of knockoffs.. Any ideas on sourcing these cells?
Take your time and get those when you're ready to pull the trigger. Getting the motor installed and building a mount for it will take some time. Right now CALB cells are pretty easy and cheap to source. A123 can be risky because of knockoffs or unknown cell conditions. Right now there are some other cells floating around for the Volt and Leaf that might work. GBS are also good batteries (also resell those).
 
#5 · (Edited)
Most I've seen use just a sprocket on the motor, long chain and a large rear sprocket. It's not actually that bad, just make sure it clears the swingarm.
I see what ya mean.. thx!

Here's a little digital eye candy for ya.. :cool:
 

Attachments

#7 ·
Your heading straight for something like my 2011 race bike only a bit heavier. You will have over 220kg especially if you put a charger on board.
You might get 150kmh top but its going to be very sluggish off the mark with the 3:1 chain.
This type of power to weight ratio should be at least a 2 speed.
This type of bike is very difficult to get right because the rear linkage suspension is right in the prime motor real estate.
Just keep thinking for a while before you start spending money.
For a street fighter you will want better accel off the mark than this.
 
#8 · (Edited)
Thanks for all the info guys! I really like to wrap my head around a project before I start (hence building everything in 3D) so I'll be listening, researching, and evolving right till go!

I changed the ratio to 1:4.5 in that screenshot for ball-parking, gotta figure out if I need to be closer to 1:4 or 1:5. New swing arm (with a thinner support OD). And different motor locations.. awesome!

If anyone has any suggestions, I'm still open to other motor/controllers but this was one of the best configs I could find for the power to weight ratio that was around 2k. Anyone know how much voltage I can put through this motor?
 
#9 ·
I changed the ratio to 1:4.5
1:4 is an overdrive.
4:1 is a reduction. Its read in the direction of power travel.

For a broad rev range you will need the highest battery voltage you can find. Sevcon wont do this, 150v max and very expensive config setup. Not even sure if the size 6 is available.
Kelly will do 52 series LiFePO4 174v 400A
http://kellycontroller.com/khb1440124-144v400aopto-bldc-controllerwith-regen-p-832.html

I have been thinking about 2 speed twin motors lately where you have 2 motors 2 controllers and 2 throttles.
One motor is geared very short for first gear like 10:1 and is chained through a one way clutch so it can throttle off without turning
the other is 3:1 for second gear, no clutch so it can do regen.

As the ZX6 swingarm is very simple you could go mad and mount both motors on the swingarm first getting rid of the single shock and linkage and replacing it with twin shocks later on.
 
#11 ·
The EVDrive packages are great little packages. They put 4 in a UTV with some high power batteries and it tore the trails up! They're already tuned and will not need extra programming unless you want to change current limits, RPM, or other simple parameters.

EVDrive is the only one that has a 150V Sevcon to go with that motor that I know of.
 
#12 ·
Sorry if this is a noob question but it's giving me a headache..
In a direct drive system (sprocket on motor, sprocket on wheel, chain/belt connecting the two) does the sprocket ratio effect the vehicles top speed?
If the top speed is simplified as a product of motor rpm (at voltage) vs tire diameter/perimeter then wouldn't the sprocket ratio effect the torque (how fast you can achieve a speed) not the limit of speed?
 
#13 ·
Ratios can effect top speed.

If you have too high of a ratio, the motor max RPM is essentially your max wheel RPM.

If you have too low of a ratio, the motor won't be in the "high power" part of its power curve.... and might not have enough power at that point to overcome aerodynamic friction.
 
#16 ·
That's a tall order.... and in single quantities, not likely going to happen for you.

The higher power you see, almost always the voltages are higher..... and so is weight.... and for that kind of power, you're looking at over $4k.

You want something cheap AND low voltage AND high power..... nothing on the market that I can think of, not under $4k.
 
#17 ·
Yeap, the goal is always just past what ya can have! Or should I just say "Stay hungry". :cool:

Ok then, what would happen if I made the motor longer?

Let’s assume that I machine a new housing that is a perfect fit compared to the original, but is 50% longer (and I have magnets to fit and don’t mind winding the new motor).
What happens to the voltage limits, amperage limits, ect of the motor?
I assume the voltage limits would stay the same (well, change slightly) and the amperage limits would increase by 50%?
 
#19 ·
Well, what have you found thus far? I think the DLC28 is a pretty good match for you, and about the highest output for that voltage level (under 200volts) in a brushless package.

Just wondering, Why do you need that high power? Is it just because bigger is better? I find that a lot of new guys think they need a huge amount of HP/kW ability..... but it isn't always true.

Remember, the Torque on these motors is huge. It could be that you're thinking you want great acceleration, which is related more to torque. HP is determined by RPM and Torque, so its possible that with the right gearing, you get the acceleration you need, but are limited to a certain top speed because of the HP of the motor.

Also, you'd need to build a 60-75kW able battery pack. At 150V, that's 400-500A. Yes, that is peak, but something to consider.
 
#20 ·
Well, what have you found thus far? I think the DLC28 is a pretty good match for you, and about the highest output for that voltage level (under 200volts) in a brushless package.
Yeah, I kinda like the EVD35..
Reputable company, comes programmed and tested, and the price is still less than "most" places. I got a few more things to decide then I'm going to give them a call about production times.

Just wondering, Why do you need that high power? Is it just because bigger is better? I find that a lot of new guys think they need a huge amount of HP/kW ability..... but it isn't always true.
Simply put? I'm looking down the barrel of a $10k+ build and want as much bang for my buck as I can get. Keep in mind, this will be used primarily for "street fighting"..

Also, you'd need to build a 60-75kW able battery pack. At 150V, that's 400-500A. Yes, that is peak, but something to consider.
Currently the pack design is 8k-10k @ ~132vdc w/ 10c pouches. I'm leaning towards the 8k side w/ a cap of 330amps (which should land me at a 30sec/6.5c cap)
 
#32 ·
It's a 60-tooth, aluminum sprocket from Sprocketspecialists. Look up your motorcycle, as the bolt-hole and alignment depend on model of bike. I looked up my 1986 Honda VFR700F and chose a 60-tooth with Titan tough anodizing.

http://sprocketspecialists.com/prod...cycle-sprocket-yrs-1987-sku-446-large-56-74t/

I gave up the project and bought a Brammo Empulse R, outlined in my blog: http://www.evfr.net/blog/

The plan was to incorporate the rear part of the frame, under the motor and above it to the front frame arms by using the battery enclosure. I didn't plan on supporting the motor plates, as they were solidly mounted to the rear part of the frame.
 
#33 ·
#35 · (Edited)
And next for the battery pack and BMS, pack first.

Still looking for higher densities (by pack volume) so pouches seem to be the answer.
Enerdel? Bestgo? Pure Power? YGS? Any suggestions and/or experiences?

The plan is 8K-10K, 132V-144V @ 55A-80A (pack configuration depends on the cells).
 
#36 ·
Look into the Leaf modules... they're priced right and available. I think you could cram at least 8kwh of batteries in a bike, probably more depending on the bike.

Enerdel is another great choice. I've used them on a race car and they were pretty solid.
 
#37 · (Edited)
Look into the Leaf modules... they're priced right and available. I think you could cram at least 8kwh of batteries in a bike, probably more depending on the bike.
Leaf modules, not a bad idea.
Pre balanced in modules of 4 and the sealed cases would make pack'ing pretty easy. They are priced pretty good at ~half the cost of the enerdel, but they are also ~half the density. So compared to the enerdel cells, the leaf pack would be ~half the cost but ~twice the physical size.

Enerdel is another great choice. I've used them on a race car and they were pretty solid.
Nice. Was probably a "bit" more than my pack. :D
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top