High power RC motor and drive unit production

[recumpence]

Hey Guys,

I am starting this thread for discussion regarding David's 60 series RC motor (currently under development) and my multi stage, modular reduction unit.

For those who are not familiar with this project, we are developing (adapting) RC technology to the E-bike realm by designing an entirely new outrunner motor (David's project) and a custom modular reduction unit for it (my project) to adapt the motor to the bike.

I am roughly 2 weeks out from having a prototype modular drive to show. I think David is a bit longer than that to show the motor.

Anyway, for those who have questions regarding the motor and/or my drive unit, ask away!

Matt

[Ypedal]

I'd like to see you working on a geared hub motor with one of these RC motors built in ! With all the tools and brains you have available i bet you could make a BMC eater..

[voicecoils]

Sounds great Have you decided on a solution to getting power to the rear wheel?

You could have a very popular ebike kit if all goes to plan

With my free X5 hubmotor, I'll be looking to jump on the RC bandwagon once a bit more refinement has been achieved. (which probably also means I'll be spending even more money!) Deecanio might even beat me too it! A viable, powerful electric drive for full suspension MTBs has great potential, but the current MTB community won't be interested unless it has impressive power. But, if they didn't have to pedal a 20kg DH bike up a big hill to go downhilling down the other side I bet there'd be interest for sure

Will the ebox production continue?

[swbluto]

What's supposed to be functionally different with the new outrunner motor being designed and the existing RC motors? Better heat dissipation, greater efficiency, greater bearing-reliability with directional stress on the shaft, etc.? I've never worked with nor have ever seen an outrunner motor(besides online at hobbycity.com) to know its issues with e-bike/e-scooter/e-what-have-you adaptation, so an abecedarian treatment might be appropriate.

[recumpence]

A hub motor is not in the cards right now.

The E-box may or may not happen. My modular design is far superior and can be configured in single stage or dual stage. So, it may be best to just build the modular system and sell it as single stage (less costly and less complicated) or dual stage (more costly with farther reduction available).

That will become apparent very soon.

I agree low weight is important for typical bike guys. That is the biggest part of this. Also, high power is important. A reliable 5kw or higher is not hard to achieve with this technology. Coupled with lithium polymer batteries, you could get away with a total drive system weight of 15 to 17 pounds with battery! That is right where I am with my recumbent.

Also, Castle Creations is just about ready to begin shipping their monster 90 volt, 200 amp ESC!

It is all coming together from a timing standpoint.

Anyway, I may fund a one-off 60 series motor for my own use and testing. That on top of a SHV200 Castle ESC and a new 1.5kwh lipo pack should put me in E-ride heaven!

The holy grail is close, very close.

The only down side is the fact that technology like this does not come cheap. David's motor will probably come in at roughly $400. My dual stage drive for that much power will be about $300 (roughly) and the SHV 200 required to run it at it's max capacity will cost $750. However, a single stage reduction will be between $150 and $200 (depending on layout), a more basic motor would be $200 to $300, and a HV110 is $250. So, you can get away with spending less for RC stuff. But, we want to see just how far we can take this ultra light weight, extremely powerful setup.

Matt

[swbluto]

So you're aiming for the stars and most of us hope you eventually land on the moon(Or offer an alternative that's lunar-nomical as opposed to astro-nomical in terms of price), at least.

[recumpence]

What's supposed to be functionally different with the new outrunner motor being designed and the existing RC motors? Better heat dissipation, greater efficiency, greater bearing-reliability with directional stress on the shaft, etc.? I've never worked with nor have ever seen an outrunner motor(besides online at hobbycity.com) to know its issues with e-bike/e-scooter/e-what-have-you adaptation, so an abecedarian treatment might be appropriate.

A few things;

#1 HUGE shaft. The internal shaft diameter is huge on this motor (I believe 15mm). The output portion of the shaft will probably be 12mm.

#2 Far better efficiency. RC planes and helis ahve alot of airflow available. So, effiency is not a big deal. But, we want the best efficiency possible. This new motor will have thin laminations and be taylor made for our application. That (among other factors) will give better efficiency.

#3 Super beefy bearings to handle the high shaft side loading a belt drive will have.

#4 Ability to handle FAR higher voltage than typical RC motors.

My Plettenberg maxes out at 50 volts. These new motors will handle 100 volts mor more!

Also, the can (bell) will be tapered to tolerate the shock loads imparted on it in bike use.

Matt

[recumpence]

So you're aiming for the stars and most of us hope you eventually land on the moon(Or offer an alternative that's lunar-nomical as opposed to astro-nomical in terms of price), at least.

Like I mentioned, a drive system can be built and sold for as little as $150 and you can get motors that are relatively innexpensive as well. So, that is not a big deal. We just want to make sure this system will handle alot of power. Going smaller is always easy.

You can go with basic components and get in for about $700 for a basic motor, simple drive, and more basic ESC. $1000 for those components will get you some nice stuff. $1500 will take you to the stars!

Matt

[swbluto]

Hmmmm... 100V*200 amps = 20KW > 25 HP. Yeah, that's sounds like the holy grail. I don't have a hard time imagining this technology would flourish among the "elite" sector of e-biking/motor-cycling if it materializes.

[voicecoils]

You can go with basic components and get in for about $700 for a basic motor, simple drive, and more basic ESC. $1000 for those components will get you some nice stuff. $1500 will take you to the stars!

For perspective, $1.5k is not outragous when serious MTB'ers spend $4k+ on downhill rigs and dirt bikes easily get to $10k+ before upgrades.

I say go for crazy performance first and let the tech trickle down to more economical lower power options. That was the Telsa Roadster plan too.

higher voltage RC motors and controllers is key, and it's great to see that it's all coming together at the right time. you guys have the tools and build experience. It's an exciting time

I'm very curious about this drive. Have you got a back of napkin sketch?

[recumpence]

You can go with basic components and get in for about $700 for a basic motor, simple drive, and more basic ESC. $1000 for those components will get you some nice stuff. $1500 will take you to the stars!

Have you got a back of napkin sketch?

Hmm, would toilet paper work?

Matt

[voicecoils]

Have you got a back of napkin sketch?

Hmm, would toilet paper work?

I doubt your idea is quite that shitty.

[recumpence]

Have you got a back of napkin sketch?

Hmm, would toilet paper work?

I doubt your idea is quite that shitty.

Oh, Man, I left myself WIDE open for that one!

Matt

[CNCAddict]

Yeah, this is all coming together pretty nicely. The motor I'm building will be "capable" of very high peak power levels somewhere north of 15Kw if it is geared correctly and run at high voltages. The problem is that the current controllers will not limit power when temps get out of hand. This is something I really worry about if Joe the plumber buys one of these. Riding hard in the mountains pulling 9Kw continuous would heat things up a lot...and ruin the motor. We need some sort of circuit to measure controller/motor temps and start beeping like mad and limit the throttle when temps get out of hand. This should be an easy project for anyone with a bit of programming skills

[kfong]

Hey this sounds interesting, I can lend a hand on the electronics/programming and any part of the development.

Kin
http://www.embeddedtronics.com/

[MitchJi]

Yeah, this is all coming together pretty nicely. The motor I'm building will be "capable" of very high peak power levels somewhere north of 15Kw if it is geared correctly and run at high voltages. The problem is that the current controllers will not limit power when temps get out of hand. This is something I really worry about if Joe the plumber buys one of these. Riding hard in the mountains pulling 9Kw continuous would heat things up a lot...and ruin the motor. We need some sort of circuit to measure controller/motor temps and start beeping like mad and limit the throttle when temps get out of hand. This should be an easy project for anyone with a bit of programming skills

Hi David,

I'd be more worried if Sarah Palin buys one (Sorry I couldn't resist).

The Eagle Tree Logger has provisions for adding temperature sensors. I don't know if it has any provision for outputting a signal that can be used to limit the throttle.

I don't need the very high power. What I want is something that is bullet proof and efficient in the range of about 2kW to 3kW sustained (hill climbing). I also don't want to run at over 36v or 48v. I want a system that is safe and reliable in the rain. That means I am going to do everything I reasonably can to make all of the electronics waterproof. But in case there is a problem I don't want to be riding an 85v system with a short circuit.

This raises a question. Will your motor or one of your motors (if you have multiple 60 series models) operate efficiently at 36v or 48v?

And a suggestion. I would do everything that you conveniently can do to encourage purchasers and make it easy for purchasers to assemble and install a system that is safe in the rain.

I also have a question for Matt. What is the approximate range of reductions that will be available with your two stage drive unit?

[recumpence]

Oh, man, almost anything is possible with a dual stage reduction.

Hmm, let's see, the primary belt drive could be as low as 6 to 1. Then the secondary drive could go as low as 4 to 1 if we really wanted to. So, that is 24 to 1 just in the drive unit, not including the final drive to the wheel.

Basically, the secondary drive will most likely be .25 chain drive just like my recumbent. That reduction could be anything from 1.1 to 1 up to about 5 to 1. I will probably make the prototype roughly 2 or 3 to 1 at teh secondary chain drive, and 4 or 5 to one for the primary belt reduction.

Matt

[CNCAddict]

This raises a question. Will your motor or one of your motors (if you have multiple 60 series models) operate efficiently at 36v or 48v?

And a suggestion. I would do everything that you conveniently can do to encourage purchasers and make it easy for purchasers to assemble and install a system that is safe in the rain.

Yeah, the motors will work great at lower voltages. They'll just spin slower Also, I plan on getting things as corrosion proof as possible on the motor. Electrically, brushless motors can run underwater. It's just the corrosion that's a problem.

[etard]

Yes a sketch please! Fingerpaint, crayons, whatever. I need to know how it can all be done on one shaft. I'm losing sleep over this. Oh yeah, can mine have lasers on it? Hehe
These are exciting times, everything is moving so fast now. I hope you guys are going through the necessary steps to protect yourself, in case any chinese manufacturers are watching this.

[recumpence]

It is truely an exciting time!

Ultimately what I would love is a light weight, but robust, E-motorcycle for all around use and an E-bike for around town bashing.

This new motor and a decent drive will definately move us closer to that goal (as will the new Castle controllers).

Now what we need is safe lithium batteries in the .20 per watt-hour price range.

Matt

[recumpence]

We (David and I) are working out the details of the first prototype motor. I am funding the first for my own testing.

It looks like we will be going with a very large diameter shaft (12mm) to start with (15mm through the bearings of the motor for better bell support). Also, I am having him tap the face plate of the motor to use two screws side-by-side per side so the pulling force on the belt will not scoot the motor in the mount.

I am excited to see this. David and I are both working hard on finalizing the details of the motor and the drive. I am making every provision I can for the drive to work with his motor and he is making every effort and provision for his motor to run well for bike use and with my drive.

The prototype motor will be 200KV. That is pretty much ideal for testing.

I am hopful that I can test the new motor before the snow flies! The new drive will be ready by then, but I will not be able to test it on a bike at that point because it would be very difficult to retrofit my recumbent and my mountain bike will not be ready by that time. I will run the motor in my existing recumbent drive, though. The production, modular reduction unit will use proven components that I am running on my recumbent (15mm wide primary belt to .25 secondary chain). That system is good for 5,000 watts minimum continuous. I have seen over 7,000 burst through it.

Matt

[deecanio]

Hi All,

Great to see all the RC info having it's own area, makes keeping up all the easier and boy is this tech moving fast.
As you all know im also looking for a new drive system for my kona, has to be fast, has to be light, has to be robust, basically RC setup capable of taking the kind of punishment shown in the video from the recent meet.
Same as all the other DH guys (we're a growing crowd don't you know) i am looking to Matt and David to produce something special here and im pretty confident that they will

a few questions though............

will the motor be controlled with the RC esc/servo approach ? weight of motor? availability date?
it seems that the motor will have some spanking specs, but if it takes fairly high voltage will the performance for say 36v users be ok? can it be geared accordingly? half of the appeal of the rc stuff for me is runing at lower voltage.

Matt,David,

i have a test bike here and good to go if you want to test the robustness of the build no problem
If you need an R&D fee let me know and we could work something out

exciting times indeed ~

Cheers,

D

[johnrobholmes]

Mind if I hop in here with my designs Matt?

[recumpence]

Mind if I hop in here with my designs Matt?

This forum doesn't belong to me. Feel Free!

Matt

[johnrobholmes]

You started this thread about your developments. When I get more news on mine I will add in my developments then. So far my machinist is "behind". He can make 400 pinions for me in 2 weeks, but can't cut 4 gearboxes in 3 months