"GT Asteroid" aka Currie Overhaul & Questions

bhartshorn

1 mW
Joined
Mar 4, 2019
Messages
10
Location
Idaho, USA
Hello everyone, just a noobie EV enthusiast here. I've wanted to build an ebike/escooter for many years but haven't had the time or means.

Anyway, I picked up this "GT Asteroid" electric scooter a while back with the intention of overhauling it with LiPo, brushless outrunner, real controller etc. It's finally time to get started! I am looking for some advice and guidance as I purchase some first parts. I should state my goals first, I suppose:

  • keep close to stock FOR NOW. This means utilize stock wheels, brakes, throttle, battery tray, etc
  • reliable (simple, robust drivetrain)
  • decent power
  • ~20 miles range is sufficient
  • I don't mind spending money on good components, but I want to keep the expensive "quality" parts to a minimum and re-use existing or buy budget parts where possible.

So, my plan right now is this:
  • replace stock motor with sensored Alien Power C80100
  • match the motor with an appropriate motor controller which can grow with the build (higher voltage, higher gearing, etc)
  • probably 48V worth of hobbyking RC LiPo packs - I will likely go higher voltage later
  • use existing chain & sprocket, changing motor sprocket if needed
  • use existing brakes, I realize they suck (rim brake and odd "band" brake)
  • use existing thumb throttle - I can hack together a microcontroller to translate if needed

Motor & Drivechain
In order to get started, I need to get the motor ordered, so I need to decide on a motor KV. I have a basic understanding of KV from building RC planes, but I'm not confident I understand how it applies to torque-y loads. I built a spreadsheet to play with gearing, voltage and KV.

Can someone take a look at my spreadsheet and check if I'm on the right track? It can be downloaded here (LibreOffice Calc format):
https://files.thehartshorns.net/f/a5e73d3821484282bfcd/

So, the existing drivetrain is:
#25 chain, 90 tooth wheel sprocket, 16 tooth motor sprocket

I would like to avoid the trouble of changing to a heavier chain and sprocket standard, but I'm not sure the #25 chain is heavy enough. The nice thing about the #25 chain is that I can very easily (and very cheaply) get different sized motor sprockets and replacement chain. Is this chain basically guaranteed to fail with the amount of power I'm looking at?

Next, motor KV:
With the existing gearing (16/90), 48V, I'm looking at a "max speed" of:
  • ~25mph for 80KV
  • ~41mph for 130KV

I highly doubt I will get ~41 from the 130KV motor at 48 volts, seems counter-intuitive from what I've seen with other builds. I don't like either of these KV options with the stock gearing, so I'm thinking about these options for gearing:

  • (18/90) with 80KV for "max speed" ~28MPH
  • (14/90) with 130KV for "max speed" ~36MPH

So, can you all help me choose? From my RC experience, I have the impression that, for a given motor size, you can squeeze more raw power out of a higher-kv motor at the expense of running hotter. I also understand that properly matching voltage and gearing probably has a larger influence.

Motor Controller
The motor controller doesn't seem like an overly hard decision, there just seems to be so many options, and I haven't seen them enumerated anywhere, so I could use some recommendations. From what I've seen regarding this motor, I'm spitballing that this configuration will be around 3-4kW, but my specialty is computers, not electrical design, so correct me if I'm wrong. From what I've seen around here (especially ElectricGod's posts), a decently-built 12FET controller should be sufficient, especially with upgraded mosfets (if needed).

I'm considering between these options:

Are there any others I should consider? I definitely want regen, and open-source/open development/frequent updates is a huge selling point for me. That said, I would like to be able to go a bit cheaper if there's something that offers competitive performance.

Motor Mount
The existing motor mount is awful. Here are a few pictures:
https://files.thehartshorns.net/d/eb5359897d944221b676/

It is sandwiched between two nuts on the wheel axle, and anchored with one bolt to the frame. Should I just use this and deal with the awkwardness, or should I try to replace it? I have access to a TIG/stick welder for a couple more months, so I could weld to the frame, but maybe there's downsides to that that I don't understand?

Anyway, thank for reading down this far. I really appreciate this community, you are a great bunch! (I've been lurking for a couple years; hah) I promise I'll turn this into a build thread when I actually get something done! :)
 
Hi There

Nice project, maybe you can post some actual
Pics of the scooter and any parts you already have ?

I’m no expert but I upgraded a curie Ezip 750 and also a 500 3 or 4 years ago and had a lot of fun with them. Now I’m riding a electric skateboard (I’m a 37 year old =) )

I wired 8 packs of 6S Turnigy 5 amp hour from hobby king to make a 12s (48v) 20 amp hour pack. That fit nicely in the stock battery compartment of both scooters.

I used a cheap 20-30 dollar 48v controller for brushed motor out of eBay, rated 1500w I think, 30 amps. And a new throttle with battery voltage indicator.

The izip 500 with the stock motor (rated 24v) run like a raped monkey with that, we’ll over 30 mph. It heated but run no problem. I actually crashed that scooter. I’ve had picked it up free from the trash anyways.

Then I bought the ezip 750 for $100 which has better brakes and front suspension. The same setup with stock motor (motor is actually the same as the 500) I GPS it at 33 mph with plenty acceleration and range.

I run that scooter for 3 months or so every day for commuting in Boston, then not surprisingly I burned the motor. I think the brushes got desolderes with the heat but everything else looked fine.

I replaced the motor with the motor from
An ezip 1000 scooter which is about double the mass and has cooling fins. That motor didn’t even get warm at 48v. It was a bit slower because it spins slower at the same voltage. I bought different sprockets to re gear and bring speed back up but never did it, it is still siting in the garage. That motor and scooter setup can easily do 30+ mph reliably all day long and is super cheap.

At some point I’ll re gear it and will replace the controller by a Kelly programable controller that can easily do double the amps if you want.

For charging I ordered a bulk charger that charged the entire pack to a final 4.05 volts per cell. Checked them regularly and never had to balance them charging up to that voltage which is about 85-90 % capacity and I very rarely discharged it more than 50% capacity, that already gave me about 10 miles of full speed riding in the city for commuting.
 
fromanoc said:
Nice project, maybe you can post some actual
Pics of the scooter and any parts you already have ?

Hey fromanoc,

I will definitely get some pictures up! It's just completely stock right now so there's not a lot to see. All I've done is yank the dead SLA's and a bunch of ugly decals. :)

I want to get the motor ordered this week so I can get a start, but I'm not sure which kv to get. Don't want to spend $200 on a motor that isn't quite what I need.
 
Alien Power doesn't make anything. They resell Chinese made motors that can be found on aliexpress and elsewhere under a variety of names. All AP does is get them silk screened with their logo on the generic motors.

The entire "AP" motor series is wound the same way. What that means is the exact same amount of copper is used on all the 100 series motors per turn regardless of the motor KV. Same for the 65, 120 and 150 sereis. Higher kv means fewer turns per stator tooth. Lower KV means more turns per tooth. Less turns means there is a lot more space on each tooth for more copper. Regardless these motors are never wound with maximizing copper fill in mind. More copper fill per tooth means more current handling and more wattage in the same motor.

The motor specs you see are fairly accurate for maximums, but for continuous use, you will burn them out running at whatever the specs say. I can speak to this as emphatically being true. So if the motor says 7kw...that really means more like 5kw continuous.

Implications of KV and other things in a motor and controller:
IE: Everything is a balancing act between different elements of the whole.

1. More turns per tooth or lower KV means the over all length of wire on a phase is also longer and this increases the wire resistance of the phase. You care about this becasue resistance is a big heat source and that's losses in a motor. IE: you want the KV to be as high as possible to minimize resistance/heat losses.

1a. A down side to low KV is the inductance of the motor is also lower and in outrunners more than inrunners, controllers have trouble detecting the motor phases correctly if the inductance per phase is too low.

2. Iron losses are another big source of motor inefficiency and heat. Faster commutation speeds increases the iron losses and that is the case with higher KV motors. Iron losses are created by switching the magnetic polarity in the stator iron. Switch those magnetic polarities slowly and iron losses are negligible. Switch them rapidly and iron losses start mounting up.

3. Less turns per tooth or higher KV means the motor spins faster. Motor max RPM = battery V x KV. So 66v x 80kv = 5280 rpm. 66v x 130kv = 8580 rpm.

4. Higher motor RPM's requires larger gear ratios to get that motor RPM down to something usable at the ground. For example on my Currie scooter at 80kv and 66v I used 3.8:1 and have a 74 tooth wheel sprocket. It's a little smaller than the rim diameter. if I had used a C80100 at 130 kv, the wheel sprocket would have been 117 tooth or so. That would have been about the same size as the tire. This of course is not doable. If the wheel was even larger...say a 26" bike wheel, the wheel sprocket would need to be like 250 tooth. You can see how high RPM motors make less and less sense with larger wheel diameters. For a skate board with a 3" wheel diameter, most of the motor RPM is directly translated to the wheel since they spin at close to the same RPM. You want simple gearing and not have it be something like 20:1. 3:1 to 5:1 is a realy wide range of gear ratios and ought to cover any scooter. All mine are in the 3:1 to 4:1 range.

5. KV, battery voltage and magnet pole pairs play into a value called eRPM. So in the case of a C80100 at 66v, 80KV and 7 poles, that's 36960 eRPM. At 82 volts on the same motor that's 45920 eRPM. This matters to your motor controller. They all have an eRPM limit. A lot of cheapie controllers found on ebay and elsewhere have 40,000 eRPM. Decent controllers such as from PowerVelocity have 50,00 eRPM, A lot of FOC controllers will have 70-90,000 eRPM a few EV controllers can go up to 120-150,000 eRPM. This limit is where the controller can't keep up with commutation of the motor and it loses sync and then the motor stops working. So from this perspective, depending on the eRPM limit of your controller you want to stay below it's maximum eRPM limit. In that regard a high KV motor is not your best choice since it will have a high eRPM. Higher battery voltage also increases the eRPM, but this matters less than the motor Kv or number of magnets in a motor.

6. 2 things play into wattage in any electrical system...volts and amps. A hair thin wire can easily conduct a million volts, but current will be a few milli-amps at most. Put 1 amp through that hair thin wire and it heats up and burns out. So then watts = volts x amps and it's amps that creates heat in a wire. Lets say your motor is 5000 watts continuous. You could run it at 48v which would mean 104 amps. At 82v, that's 61 amps. Less amps means less motor heat and you want this.

7. BLDC motors run best in their mid range of RPM's...say from 20% of maximum to 80% of maximum RPM's. At the lowest and highest RPM's they suck down the most current with the least amount of benefit. IE: Keep the motor running in that mid range as much as possible. This plays into gearing and battery voltage. With more battery voltage you extend that 20-80% range over lower battery voltage. With gearing, too close to 1:1 and the motor spends too much time in that lower 20%. Too far from 1:1 and the motor spends too much time above 80%. In either case it is less efficient and generating more heat. Of these two, it's better to gear a little too far from 1:1 than it is to gear too close to 1:1.

I've probably forgotten to mention something here...sorry about that! This does cover a lot of things to think about when designing for your EV.

The shorter version:
1. Go with the highest voltage possible that your controller can handle reliably to reduce phase current as much as possible.
2. Use gearing that puts the motor in that 20-80% RPM range as much as possible.
3. Keep in mind the eRPM limit of your controller so your motor isn't spinning faster than the controller can keep track of.
4. Gear ratios get very "tall" with high Kv motors.
5. Use the highest KV you can use without breaking the other items.

The really short version:
In the case of the C80100 on a small scooter like the Currie, 80 kv at 66-82v on a 50,000 eRPM controller is pretty darn good and balances all the different things that play into the build fairly well.

Even if I had a faster controller that could handle a higher KV C80100, for the gearing alone, this is NOT compelling.

The C80100 at 80kv will serve you well, but you will want to reinforce the shaft to bell union. It's just too weak to hold up to driving from the shaft. I created this thread on that subject. You are applying a lot of torque to the motor shaft. From the chinese factory, all that's holding the shaft to the bell are 2 small set screws. I only recommend running an outrunner from it's shaft out the bottom of the motor. If you do run from the top of the bell, be sure to support the end of the shaft. The motor will evenetually break in half if you don't. From the bottom of the motor and driving from the shaft is the best option, but you will need to reinforce the shaft to bell union.

https://endless-sphere.com/forums/viewtopic.php?f=30&t=90264

Get the motor with the hall board.

Replace the factory bearings. They are cheap and NOT sealed and will fail quickly when dirt and water gets inside them. All ceramic, sealed bearings are expensive but really good. Hybrid, sealed bearings are lots less expensive and still have 80% of the benefits of all ceramic bearings. As a minimum you want sealed steel bearings. A full replacement set in all steel will cost around $25 and is 100% worth it. Don't get Chinese bearings!!! NSK and Nichi will always be good quality. Chinese bearings tend to be sloppy and low grade. Not worth the cost savings.
 
Read through my Currie thread!

Expect those spoke wheels to not last. My front wheel was OK-ish, but the back wheel could not hold the motor torque and I broke spokes. I got cast wheels and that has been a significant improvement that is highly reliable.

Tires are a problem. There are some that hold up to the torque and loading, bot lots that just wear out fast. 80% of tires in this size are meant for children's bikes and low powered scooters. I went through 3 sets of tires before I got the ones on the Currie now. They had weak side walls, wore out rapidly or in one case developed a giant bulge from the laoding. I can point you in the right direction to better tires, but they won't be in the $5-10 range like most of the crap is.

Once you have good tires and decent cast wheels, you still have a tire problem to resolve. At the back wheel, grip between the wheel and tire bead is insufficient to hold the motor torque. You will need to go tubeless and glue the tire to the rim. The front wheel now sees lots more loading too when braking and the tire migrates on the rim too. Using tubes means slowly over time you will shear off the valve stems on both wheels. AKA go tubeless and glue the tires to the rims.

You will need to reinforce the back section of the scooter. Again...not designed for 4-5kw and it will need to be strengthened at least for how the motor mounts to the frame.

The bolt that holds the handlebars to the forks is too weak. It's 8mm steel. I replaced it with a 10mm 10.9 bolt after I snapped off the original one. That was fun!

If your scooter lacks front brakes or doesn't use disk breaks, you will want this. These little scooters were not designed around 45mph and 5kw or the added weight. Slowing it down is now much harder.

I don't know about your scooter, but the Currie battery bay was really small and used about 1/2 the space available. I removed the factory one and made my own.
 
ElectricGod said:
Alien Power doesn't make anything. They resell Chinese made motors that can be found on aliexpress and elsewhere under a variety of names. All AP does is get them silk screened with their logo on the generic motors.
I had no idea they are a rebrand. Good to know! I looked it up and they're still ~$200-250 on aliexpress, so I suppose AP isn't marking it up too terribly bad..

ElectricGod said:
The really short version:
In the case of the C80100 on a small scooter like the Currie, 80 kv at 66-82v on a 50,000 eRPM controller is pretty darn good and balances all the different things that play into the build fairly well.

Even if I had a faster controller that could handle a higher KV C80100, for the gearing alone, this is NOT compelling.
Yeah, I was looking at my gearing options for the 130kv and it's definitely not optimal as you mention. I'll get an 80kv on the way then :D

ElectricGod said:
The C80100 at 80kv will serve you well, but you will want to reinforce the shaft to bell union. It's just too weak to hold up to driving from the shaft. I created this thread on that subject. You are applying a lot of torque to the motor shaft. From the chinese factory, all that's holding the shaft to the bell are 2 small set screws. I only recommend running an outrunner from it's shaft out the bottom of the motor. If you do run from the top of the bell, be sure to support the end of the shaft. The motor will evenetually break in half if you don't. From the bottom of the motor and driving from the shaft is the best option, but you will need to reinforce the shaft to bell union.

Replace the factory bearings. They are cheap and NOT sealed and will fail quickly when dirt and water gets inside them. All ceramic, sealed bearings are expensive but really good. Hybrid, sealed bearings are lots less expensive and still have 80% of the benefits of all ceramic bearings. As a minimum you want sealed steel bearings. A full replacement set in all steel will cost around $25 and is 100% worth it. Don't get Chinese bearings!!! NSK and Nichi will always be good quality. Chinese bearings tend to be sloppy and low grade. Not worth the cost savings.
I have looked over your reinforcement thread and it looks fairly straightforward. One thing that wasn't clear: I'm assuming the motor comes with the shaft extending from both ends. Do you just cut extra the shaft off after reinforcing the bell side?

Do you have the bearing size handy? Would like to just get better bearings ordered while waiting on the motor. I've dealt with sealed bearings on motocross wheels, it's nice just not having to worry about it!

ElectricGod said:
Read through my Currie thread!

You will need to reinforce the back section of the scooter. Again...not designed for 4-5kw and it will need to be strengthened at least for how the motor mounts to the frame.

If your scooter lacks front brakes or doesn't use disk breaks, you will want this. These little scooters were not designed around 45mph and 5kw or the added weight. Slowing it down is now much harder.

I'll go through your thread again. I am concerned about mounting the motor because the stock mount is just lame. I'm also not sure I can pull off disk brakes yet. I'm hoping to keep the built light and underpowered initially and build as I have time and money. Maybe the stock brakes won't get me killed if I take it easy? :lol:

ElectricGod said:
I don't know about your scooter, but the Currie battery bay was really small and used about 1/2 the space available. I removed the factory one and made my own.
It's definitely not huge. I think I'll try to find some sheet steel and extend it, but that might be a bit precocious. I don't particularly care for how it mounts, either, but I'll spend some time pondering that issue.

Thanks a bunch for all your input! I really appreciate it. Just one more question: it looks like you've worked with all 3 motor controllers I'm considering - the PowerVelocity, the Grinfeon (https://www.ebikes.ca/shop/electric-bicycle-parts/controllers/c7240-gr.html), and the Nucular.

It looks like the PV and Nucular both have bluetooth, but I haven't seen the Nucular app. I'm assuming the PV app is decent?

I really like the look of the Nucular display. Does the PV have something similar? (Cycle Analyst?)

What do I lose if I go with the Grinfeon? (Is it even powerful enough for this motor @ 72v?)

Thank you again for all your time! Your build is what inspired this project. :)
 
bhartshorn said:
I have looked over your reinforcement thread and it looks fairly straightforward. One thing that wasn't clear: I'm assuming the motor comes with the shaft extending from both ends. Do you just cut extra the shaft off after reinforcing the bell side?

Do you have the bearing size handy? Would like to just get better bearings ordered while waiting on the motor. I've dealt with sealed bearings on motocross wheels, it's nice just not having to worry about it!

Off hand I don't know the bearing numbers. Once you have the motor, you'll see them stamped on the side of each bearing. There's 3 or 4 shaft bearings and 1 skirt bearing.

Yes the motor comes with shaft sticking out both ends of the motor. You have plenty of length out the bottom of the motor for mounting a sprocket. Reusing the bottom part of the prop adapter for your shaft reinforcement is ideal and pretty easy to do. You can cut off the extra length of shaft coming out the top of the motor a little longer than the bottom section of the prop adapter. The threaded end of the shaft is the "top" of the motor and where the prop adapter mounts. You want to be uber careful to keep metal bits out of the motor. Fortunately this motor comes apart pretty easily so you can set aside the stator and bell to keep metal out of them while you work on the shaft and bell to shaft adapter.

C80100%20outrunner%201_zps1lhrydjm.png


bhartshorn said:
I'll go through your thread again. I am concerned about mounting the motor because the stock mount is just lame. I'm also not sure I can pull off disk brakes yet. I'm hoping to keep the built light and underpowered initially and build as I have time and money. Maybe the stock brakes won't get me killed if I take it easy? :lol:

Yeah the factory motor mounting is just a piece of stamped sheet steel on all these small scooters. Pretty lame and way too flexible. You will want the motor mount stiff and unmoving. Steel will work and that makes welding it pretty easy too. I went for aluminum since it's lighter and can be assembled with screws easily. If I had a TIG welder, I would have considered welding.

If you look in any of my EV build threads, you'll see that I use 219 chain and sprockets. You will need it for the C80100! I don't know what's on your scooter, but more than likely it is T8F or something lighter. Those chains are fine up to about 2000 watts and then they break all the time. You are going to be using a 4-5kw motor...that means you need 219 which will handle up to about 10kw. I would not waste my time trying to get lighter grade chain to work here. It will be a constant problem for you. I ran on T8f on my first build for about a year. Everywhere I went, I always carried spare chain and a chain breaker with me. It was going to break and leave me stranded somewhere if I was not prepared. I averaged a T8F chain break every 20-30 miles. With 219, I have had 1 chain break in 10,000 miles of EV riding.

bhartshorn said:
It looks like you've worked with all 3 motor controllers I'm considering - the PowerVelocity, the Grinfeon (https://www.ebikes.ca/shop/electric-bicycle-parts/controllers/c7240-gr.html), and the Nucular.

It looks like the PV and Nucular both have bluetooth, but I haven't seen the Nucular app. I'm assuming the PV app is decent?

I really like the look of the Nucular display. Does the PV have something similar? (Cycle Analyst?)

What do I lose if I go with the Grinfeon? (Is it even powerful enough for this motor @ 72v?)

I voluntary help develop the PV product line. I do software testing for a living and have an EE degree so this was a fun project to get involved with. The telemetry module will work with just about any EV and runs at up to 150 volts. The module is the hardware that does all the monitoring of the EV. It then transmits it's data via BT to your smart phone. IMHO, there is no EV app and hardware solution for monitoring that is as good as the PV solution. It has GPS, can program all the PV controllers, can connect to and monitor a selection of BMS's and of course display speed and typical battery stuff that is the "stuff" everybody elses apps can do. The android or IOS app is pretty darn good., No one else has anything as good or as complete that isn't also proprietary. Our solution was designed to work with anything. There will be some functions that may or may not work depending on your specifics, but anything a CA can do, the module and app can do better. Also, it is always seeing new development. Just a year ago we added GPS mapping as a major new feature. Just a few months ago, we added BMS monitoring support for some smart BMS's. There's functionality on the module we haven't begun to use and a list of new major features in the app at least 50 long we haven't gotten to yet. I'm biased...admittedly so...but no one is doing what we are doing with an EV monitoring tool that can work on anything.

PV controllers are highly hackable. If you like messing with things and seeing what you can do to a controller to make it stronger, this is a great controller series to mod! I have all of the product line and so far I have modded all of them for some new feature or more power. When I got my first 12 fet, I was immediately looking at how to improve it. They originally sold as 3kw and soon I had them going strong at 4-5kw like they are sold now. I've since built a few where they are running at 6-7kw. It's a highly capable platform for hacking and modding if that's your thing. They are sinusoidal, but not FOC. FOC will get you a bit more performance out of a motor than will a sinusoidal controller. You are limited to 50,000 eRPM on the current PV controllers. We are working on getting that higher, but that's not live yet. The controllers come in 100v and 150v versions. For the price and features you get, these are very nice!

Don't waste your time on the Grinfineon controllers. I have had 3 and sold all of them shortly after they arrived to me. They are a dumb controller that can't be programmed at all. You want a programmable controller such as a PV or Nucular.

Nucular is pretty new to the market and I have to say that the 12 fet controller from them is really nicely made. They pay attention to detail and make a solid product. I have not seen BT support for it, but you don't really need it. 100% of the controllers functions are accessible via the LCD. Their 12 fet controller would be a good match with the C80100 and it is FOC...so that will get you a bit more out of the motor than the current PV product line can deliver. I think their soon to be released 24 fet controller will be a really good option too. I've attempted to get an eRPM limit for these controllers, but that's not something I've been able to pin down. However, it's going to be something like 70-80,000. These controllers have my attention! If I have a complaint it's that the LCD solution is proprietary and works only with Nucular controllers.


At 82v and an 80kv C80100, either the Nucular or PV 12 fet controllers will work well for you without exceeding eRPM limits.
 
A little update. I have the motor ordered, but I'm not sure how long it will take to ship. Looks like it comes from somewhere in the UK, which I have no experience with. In fact, I had to call my bank to allow the payment to go through, hah. Anyway, I'm anxious to get my hands on it so I can make some final plans for the motor mount.

5a49fc48fc3b4e8fab21


I've been tinkering with an idea I have using FreeCAD. It's a motor mount in which the motor "swivels" on one of the bolts to tension the chain. I'm not sure I can get the travel I would need with this design, so I may just switch to straight slots. I'm just worried that with straight slots, the motor would have a tendency to slide towards the wheel. I haven't mocked up the slot for the motor shaft yet, either. This would use 3" x 4" aluminum angle, I'm not sure what thickness yet (this mockup is 1/4" which I would think is plenty.) My friend has a CNC mill with end cutters, though he has never used the CNC functionality. This design would probably be hard to cut by hand with the mill, but I've never used one so I can't say for sure.

Hoping to get the motor controller ordered soon, but ElectricGod really made me conflicted between the PV and Nucular controllers. I was set on the nucular, but I really like that the PV controller is hackable and it seems to have all the functionality I need. The only thing it doesn't seem to do is variable regen. I would love to hook up a potentiometer to the brake handle and have variable braking instead of just on/off. I also don't know much about the FOC control method. It seems like the hot new thing, but is it a big enough benefit to make the decision between the two controllers?
 
fddc8d17b79b4228bfa0


So here is with the slot for the motor shaft and the resulting distance of travel. It will be ~12 mm less that that for the shaft width for a total of ~30mm = ~1.2" horizontal travel. I could increase it a bit more also. Looks like maybe enough to try it. For science!

(I'm surprised I was unable to find more info on the web about motor mounting with built in chain tensioning. I really don't want to run a separate tensioner with idler.
 
I like the idea, but it will have issues. The chain will pull inline with those slots and pull over the motor slowly. No amount of cranking down the screws will hold it in place. You need your "under tension" point to be more or less 90 degrees from the direction of force. Your plan can work, but rotate it. I like the single screw that it all pivots around. I think I'll machine something like this and play around with it. Rotated over so the pivot screw is inline with the drive side of the chain and the top of the screw slots are slightly further than the tension point would work better than my vertical slots. All the way down would create a good bit more slack.

Your curved slots need to be rotated another 45 degrees. As is, the red line is your current direction of pull on the drive side of the chain. The center of drive (blue circle) is below this line and that will make the motor migrate towards the wheel creating chain slack. The green line is what you want and puts the center of drive in line with the pivot screw and in the path of the drive side of the chain. Also, rotate it a bit more. New chain stretches over time and what's a perfect fit today will be loose in a few months of use. Pretty much 10-15 degrees either side of perpendicular to the drive side of the chain won't move.

motor%20bracket%202.png


This never migrates at all in the slots since the drive side (top) of the chain is 90 degrees to the slots. All the way up pulls out chain slack with a little extra room in the slots. All the way down makes just enough slack to get the chain off the sprockets.

Driver%20sprocket%202_zps02tcayco.jpg


Driver%20sprocket%202_zps02tcayco.jpg


Driver%20adapter%202_zpsv7ftlyjc.jpg


Motor%20Bracket%204_zpshp0o3kwb.jpg
 
ElectricGod said:
You want to be uber careful to keep metal bits out of the motor. Fortunately this motor comes apart pretty easily so you can set aside the stator and bell to keep metal out of them while you work on the shaft and bell to shaft adapter.

It has been foretold!

Here is my poor-person machining job:
2becbd5749e54a99a85f

fd825971900341f78205


Should hold tight, right?

I like that this motor uses 5mm threads for basically everything I will need to mess with. But anyway... I got some metal scraps in it. I stuck a bag over and did my best to seal it up but they managed to get in anyhow. So now, I'll be experimenting with how to get it apart to get those out. I was hoping to not need to open it up, but c'est la vie.

This thing is quite a bit bigger than I imagined. The pictures just don't do it justice. I'm excited to get it on the scooter. :mrgreen: In other news, the controller should be on its way soon also. The last big purchase left then is batteries.
 
Got my motor apart tonight. It really wasn't hard, but it would have been nice to find some info on how to do it. I'll post some pics later of the important steps. I'm hoping that I didn't nick the enamel on the windings. I realized after giving the stator a tug that the "rear" bell support was being pushed into the windings.

We'll find out if my controller ever ships. I made my order from powervelocity.com almost 2 weeks ago now and haven't received anything besides a payment confirmation. Is this normal?

Finally, here are bearing numbers for anyone who wants to replace bearings in their own APS C80100:

"skirt" bearing (large one in "back" of motor) - (45 mm ID, 58 mm OD, 7 mm width)
NSK 6809Z - Replace with
NSK 6809V - for a "non-contact" sealed version
NSK 6809DD - for "contact" sealed version
http://blog.misumiusa.com/ball-bearings/deep-groove/6809-ball-bearings-45x58x7mm-z-zz-2rs/

Shaft bearings (2) - (12 mm ID, 21 mm OD, 5 mm width)
NSK 6801Z - replace with
NSK 6801V - for "non-contact" sealed version
NSK 6801DD - for "contact" sealed version
http://blog.misumiusa.com/ball-bearings/deep-groove/6801-ball-bearings-12x21x5mm-z-zz-2rs/
 
bhartshorn said:
We'll find out if my controller ever ships. I made my order from powervelocity.com almost 2 weeks ago now and haven't received anything besides a payment confirmation. Is this normal?

Mine took about two weeks or so. Don't worry, he's a good guy, just a bit over-worked and under-loved...

M
 
bhartshorn said:
Got my motor apart tonight. It really wasn't hard, but it would have been nice to find some info on how to do it. I'll post some pics later of the important steps. I'm hoping that I didn't nick the enamel on the windings. I realized after giving the stator a tug that the "rear" bell support was being pushed into the windings.

BTW: The shaft has 1 bearing at the motor base and 2 at the top of the stator. This is in addition to the skirt bearing.

You duplicated what I did for shaft to bell reinforcing. In that same thread I showed how to get the motor apart. This works really well and is very controllable so the magnets can't slam into the stator and get broken.

C80100%20bell%20-%20puller_zpsewq8ux31.jpg


If you never ran the motor with metal bits in it, you are probably OK. Just be sure to get all the metal out of the motor before you spin it up.

There's 2 bearings here. Maybe you have a flat washer that sits on top of the bearings that sits between the bearing inner race and this cone section? If the bell won't "drop" onto the stator far enough, then the skirt bearing carrier will be pulled into the windings at the base of the motor. I ran into that problem from NOT having the 2 bearings at the top of the stator pushed in all the way.

C80100%20hall%20board_zpsr2lzj0ox.jpg


C80100%20inside%20bell_zpsayrlfp4y.jpg
 
MJSfoto1956 said:
bhartshorn said:
We'll find out if my controller ever ships. I made my order from powervelocity.com almost 2 weeks ago now and haven't received anything besides a payment confirmation. Is this normal?

Mine took about two weeks or so. Don't worry, he's a good guy, just a bit over-worked and under-loved...

M

Don't worry Vadym (PowerVelocity) is a stand-up guy. You will get your controller! I've been working with him for a couple of years now.
 
I assume you are using 219 chain and prockets. It's the best choice for this size motor and the cost for parts is pretty low.

Do you have an adapter for the 12mm shaft to 3/4" ID of the 219 sprockets?

You will need one of these. This is a section of 3/4" keyed shaft and I mill out the ID to 12mm.

Motor%20shaft%20to%20sprocket%20adapters.png


Not applicable to your motor, but the same part milled to 15mm ID. It's more of a spacer or sleeve now.

Shaft%20to%20sprocket%20adapter%204.jpg


Sleeve%20in%20sprocket%201.jpg


You will drill 2 holes through the adapter and through the shaft to lock them together via a couple of hardened steel pins. HSS drill shaft works great for this. I completely sealed the motor in tape before I started anything.

NOTE: You probably already know from drilling those dimples that the shaft is really hard stuff. I use carbide drills. HSS drills dull rapidly when cutting this stuff. Also, as you can see, I'm set up to do this sort of work. If you want, you can send me your motor and I'll set you up like you see here.

Motor%20ready%20for%20drilling.jpg


In the vice and ready for drilling.

Motor%20in%20vice.jpg


Motor%20lined%20up%20for%201st%20hole.jpg


You are going to make tons of steel bits as you drill these holes. All that tape completely encasing the motor kept 100% of metal contamination out of the motor.

Motor%20first%20hole%20done.jpg


Motor%20lined%20up%20for%202nd%20hole.jpg


All done. I scrounged a couple of cheap drills that are a snug fit in the holes and cut of the shanks to use as hardened pins.

Motor%20drilled%201.jpg


Motor%20drilled%202.jpg


The motor will be covered in metal bits. I cleaned it all off as best I could with my fingers. Then I used the sticky side of more tape to stick to the remaining metal bits. Once I was satisfied I had all the metal off the motor, that's when I finally unwrapped it.

C80100%20completed.jpg
 
bhartshorn said:
This thing is quite a bit bigger than I imagined. The pictures just don't do it justice.

This is a strong motor and very compact for what it delivers to the wheel. IF you think it's big, let me give you a little perspective...
(I have all of these motors)

An HLD inrunner with nearly identical capabilities. It's probably 40% larger and 2X heavier.

Big%20block%20vs%20C80100_zpsgnp6xgwp.jpg


This black CA80-160 is exactly the same size as the C80100...next to an 8kw, 100mm outrunner.

RV-100E%20vs%20CA80-160%201.jpg


RV-100E%20vs%20CA80-160%202.jpg


The left most outrunner is 120mm and 10kw. Next over is the above 8kw outrunner and 2 other 100mm outrunners.

Revolt%20outrunners%202.jpg


That left most 120mm outrunner shown above next to an Alien Power 12090 120mm outrunner. They are pretty close to the same size.

RV-120-reg%20vs%20PV%2012090%204.jpg


RV-120-reg%20vs%20PV%2012090%201.jpg


That CA80-160 which is the same size as the C80100 next to the alien power 12090.

Motor%20comparison_zpsgw7mwjb8.jpg


And then BIG...a Motenergy 3031-001 axial flux 80kw motor next to the AP 12090. It has two 180mm wide and 76mm tall stators. It makes a motor 2X more powerful than the C80100 look tiny. No surprises since it's 8X more powerful than the 12090.

PMAC%20vs%2012090%204.jpg


P1020430.jpg


The magnets inside the 3031-001 are the same diameter as the C80100 stator diameter!

3031-001%20magnet%20close-up.jpg


C80100%20ceramic%20bearing_zpsa9qojzut.jpg


Your "big" 5kw C80100 next to the 80kw Motenergy 3031-001 motor. What were you saying about the C80100 being big? I forgot! :)

CA80-160%20vs%20Motenergy%203031-001%201.jpg


CA80-160%20vs%20Motenergy%203031-001%202.jpg


This is 80kw, vs 40kw vs 10kw vs 5kw. "Big" is a matter of perspective... ;P

4%20motor%20comparison.jpg
 
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