jonescg's NEW electric racebike BUILD thread!


100 MW
Aug 7, 2009
Perth, Western Australia
This build log is over 1300 posts long, and spans over a decade!
Post #1 is me musing how to go about building a more reliable, faster e-moto.

In October 2022 I decided to get the band back together and build a new battery and get Voltron back on the racetrack. Comeback build log starts here on post #1277!

Historical build log starts here:

Hi All,

With the Australian TTX-GP still to run it's full course I have begun researching my next bike. I've learned a lot from building Voltron, and I think I have gained enough knowledge to embark on another year-long project.

The next bike will use a CBR1000RR chassis. I'm checking out a few bikes online and at repo auctions, but my heart is set on a late model, preferably 2008 onwards. Unfortunately most litre sportsbikes have engines that outlive their frames, as the frame is jammed under an SUV somewhere :(

So with the rolling chassis in mind, it's time to think about the electric bits.

Motors. Everyone goes on about batteries as if they are the biggest limitation to electric vehicles, but I firmly believe that there are more options for performance with batteries than you do with motors. Motors take up a big chink of the bike, and weight a fair bit too. More development needs to happen here! Anyway, what are my options?

MARS or ETEK? Gutless.
Agni? Ok, but you need to pair them up, and if you don't melt them you have 60 kW peak. Not enough.
EMRAX? Looking better, but you still have to pair them up and run two controllers. The outrunner thing bugs me too.
Brusa? Crazy motors - bit porky for their output though.
UQM? A solid motor with insane power, but it's a chunky sod. And did I mention the price? $22,000 including the pizza-box sized controller?

So quality and power is proportional to cost... Nothing new there. At this stage, I am leaning towards the UQM Powerphase 125, or if I can shoe-horn it into a 'Blade, the 145. I have written to them to see if they will sponsor Team Voltron. Always worth a shot. I am open to other suggestions of alternative motors though. Most will need water cooling, which isn't a problem with todays technology.

High voltage AC controllers are huge, and I'm not sure where to fit them. I've drawn a bit of a mock-up to estimate where things could go:

It will seriously affect the bike's lean angle down there, but it might work. Otherwise under the tank? Or as Chip Yates did, pizza-box behind the seat can work with some clever fibreglassing. It still weighs 13-16 kg, so that's a LOT of weight to have over the rear wheel = failbike. Hahaha! I just realised my race number is the same as Chips! :lol: What a coincidence :)

I want the total capacity to be about 7.5 kWh. As I can get access to A123 pouches this could be a safe, convenient option for energy storage. 113 cells will give me a capacity of 7.6 kWh and a hot charge voltage of 412 V, but is sure to stabilise around 380 V. This voltage is ideal for running most high-powered AC motors, and the controllers can use IBGTs. Unfortunately, 113 cells needs a careful arrangement of cells to make sure it all fits, and makes use of the space available. Fireblades, like most Jap IL4s are right fattys, so width is your friend. Still trying to arrange these large format pouches in an efficient, yet convenient way. Cell weight would be about 55 kg.
I was hoping to use acetal plastic to make it like Daniel's bike; super convenient to rip out when you need to. An idea for a tall stack is below, however, this is too tall, and I would probably do something like the image above to get the weight lower where possible:

Another alternative is using the 5 Ah 40C Turnigys and making a stack 84 cells high and 5 cells wide (105 S 4 P, 388 V, 430 V hot). Being much narrower, this leaves more room for motors and controllers etc. Balancing them will be a matter of multi-pin plugs in the right spots, with appropriate BMS/monitoring wires everywhere. This pack would also weigh 55 kg. despite their safety issues, this would give me a very energy dense pack, and slightly higher total capacity ~7.7 kWh.


The wet kerb weight of the Blade is just under 200 kg. So this bike needs to be the same or less. 55 kg worth of cells, 42 kg worth of motor, 16 kg controller, 80 kg rolling chassis, and maybe 15 kg for miscellaneous stuff is 192 kg. Sounds easy when you say it fast :lol:

How do I explain my proposition to Katherine... well anyway, if I have to pay full price for a motor, it's going to be one expensive mothertrucker of a bike. Rolling chassis might be 3 to 5 thousand, even better if I can sell the IC bits. Cells will cost somewhere between 5 and 6 thousand, motor and controller will be somewhere between 10-22 thousand. I really want them to sponsor me!!

Anyway, watch this space. It will eventually populate with my expenses... But it will be one mean mothertrucking bike :twisted:
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Nice! go Chris! CBR1000RR is a fantastic chassis to start with from my perspective.

Can't really beat Agni's power-to-weight including controller can you? I'm very interested in 3 phase, real-deal motors for practical motorcycles with maintenance intervals in miles/kms not laps/minutes. I'm checking out UQM now...

Agreed though. Batteries are there, they will get better, but they're no longer the limiting reactant.

EDIT: wow 110lbs for 195hp with the UQM? That could be worth it... you then have the problem of building a 400+V battery pack, and not burning up all your power in the first lap... Wow those are nice though.
Really hope you can pull this one off Chris.

Some Australian made candidates to consider would be: for the motor. I think they are developing a smaller sized Carbon motor. for the controller. The wavesculptor200 is very compact for what it can do.

The Australian made angle may also be a plus as far as sponsorship is concerned.

Mat B
Wow, Tritium's controller looks perfect! The Ultramotive motors look cool, but a bit bulkier than the UQM. Also need to find out the price... I wonder if the Wavesculptor can power the UQM?

Thanks for the links :wink:

Hi Chris,

Compared to the UQM Power Phase 125, Ultramotive carbon motor is 1kg lighter as well as having a higher power density.

UQM Power Phase 125: Power density (based on 125 kW peak) 3.05 kW/kg

Ultramotive carbon: Power density (based on 150 kW peak) 3.75 kW/kg

I dont think the Ultramotive carbon motor is more bulky than the UQM Power Phase 125, but then again there's not much info available for the carbon motor. I still think you should have a chat with Ultramotive guys.

Mat B
Well I just went and measured up a few different bikes for space availability, and it looks like the GSXR1000 has a more spacious under-tank volume, with the R1 being second, CBR1000RR third and the ZX10 last. Still, I won't really know until I can get a hollowed-out rolling chassis to work with. However, the Fireblade is without a doubt the nicest bike to ride, and althoug it will be tough to break my Honda fan-boy ways, I might have to resign to a Spewzuki. So I will keep looking around. All three bikes had enough room for a 250 mm deep motor where the gearbox resides, meaning a UQM or Ultra motor will probably fit in there, but the >280 mm diameter of these guys means there is not much room left for batteries down low at the front. An alternative might be to shift the motor to the front and run a reduction drive to the pivot point:

This still means a lot of weight of batteries up high, so I;ll have to think a bit more about this one. Dammit I really need an empty bike to work on!
CHRiS why such a large chassis I would
have thought a 600 chassis would have been
a better choice still more room than the 250
(which you did fit everything in) and lighter than a 1000?...anyway batteries, have you tossed
around laying them longitudinally i think
they will fit no?


Best of luck..

Not a bad idea on the battery stacks KiM :shock: It would almost be easy enough for one person to tug them out too.

A 600 chassis doesn't really offer much of a weight reduction than a thousand, 10 kg at best. The thou's are a little bit wider across the bow, which helps when trying to fit more cells in. With the motor power I have in mind I'll certainly need the extra capacity anyway. I managed to fit everything on the RG cause the Agnis were able to free up an extra 30 mm inside, meaning I could fit the stack of 48 cells in the engine bay.

Shame someone doesn't make a powerful synchronous motor with a long profile but no bigger than 250 mm diameter.
Exciting times :)

I want to see what the RG Voltron can do in September first!

But, thinking about next year...

I think you're on the right track with litre chassis and a single big ass motor. Which class would you aim for? TTX75 or the eFXC?

The Wavesculptor 200 looks perfect. I've been eyeing it for a while too. Could you fit it along the bottom/underside of the bike between the wheels? Nice and close to the motor that way!
Hehe, yeah Voltron will be a bit better prepared next time I hope. I'm definitely going to put the larger rear sprocket on. Seems getting out of corners was where a lot of medium to high load was coming from. Sticky tyres would help too, but that's $400 I won't have.

TTX75 is limited only by the capacity of your batteries. Daniel was in the open class (I think) because he first registered with a 7.8 kWh battery, but not only this he could have two smaller hot-swappable packs, even if they were less than 7.5 kWh. I don't know whether both classes will be merged, or the rules will be more specific, but affordability was the main reason for two classes. Although, with big motors like UQM or Ultra, affordability goes out the window :lol:

Either class needs to be under 250 kg, I think.

The Wavescuptor is narrow and long, so it can even go under the seat. But under the motor is a convenient spot for sure. Keeps the water pipes and cables nice and short. I found a 2004 CBR1000RR that had been crashed for $3k, might be able to talk down to 2. All the IC stuff is good and sellable.
Holy shit! That's a steal!

*quickly makes bid*
jonescg said:
Holy shit! That's a steal!

*quickly makes bid*

Tiz 'Pick Up Only' Crhis and shes in Frankstown Victoria
know anyone there that could pick it up for you and prepare it to ship?

Yeah I got stacks of biker mates all through Vic. Looks like someone is watching it - gone to 1575 already. I better ask the Mrs before I go doing something silly ... ... :p
How long is the distance that you want to race?

With less than 8kWh you will run out of capacity after 12miles or 20km. The load on the batteries is 15C, the voltage will drop a lot.

Good luck with your project.
The eFX/TTX-GP races are all 20 to 25 km, so 5 laps of Eastern Creek, 7 laps of Winton Raceway and 8 laps of Wakefield Park. From experience, I had almost half a pack left after the race at EC, and that was with 6 kWh on board. So batteries are not a problem.

Granted the bigger motor and heavier bike will draw more juice, I can't see it being a problem really.
Can't wait to see this come along Chris. The 1000 fireblade will be a sweet frame as a basis in my opinion. It's just on a year since I sold my CBR900 Fireblade, under orders of she-who-must-be-obeyed. Shortly before that I also basically gave away a running but unregistered GSXR750 for $700 because I was moving house and had nowhere to put it.

As you say, most of them (if being sold cheaply) are covered in blood and brain, and less than structurally sound. I presume you have tried all the wreckers and local mechanics obviously? Might be worth putting up a notice at the local mechanics that you are interested?

Have you considered the older GSXR1100s? They were pretty ahead of their time re weight and handling (I am only thinking if you need to go super budget).
Nice seconda build it may even be better then the first one! why not use a gsxr? I thought the were the best litre bikes in the world? also what about rewinding and water cooling and adding sensors to an rc motor?
I am open to any litre bike with enough room to fit all the goods. I'm just a bit of a Honda fan-boy, that's all :) But yeah, looks like the Gixxer thou would be a much more spacious frame. I need to calm down and save a bit of cash first. The rest of the season with Voltron isn't over yet, and there's a lot more money to spend.

Re: rewinding an RC motor? No way it would have the poke to haul ~195 kg out of a corner. Unfortunately this bike won't be a cheap one (not that Voltron was in any way cheap) but I also learnt that old motto: 'do it properly the first time' yada yada. A big powerful synchronous AC motor is the only way I'm going to get the drive I need.

I can enter into either class, so more batteries is no drama as long as I can fit them in. I still want to keep the weight below 200 kg if possible. I thought about of setting the motor a tiny bit lower to keep the CoG low, and stacking the cells as two racks into the guts of the bike:


It does mean a separate reduction chain, but this could be worked out somehow. Either A123s or Turnigys will work, I'm hoping the A123s some through though. Fewer cells to muck around with, and much safer chemistry.
MIB said:
Really hope you can pull this one off Chris.
Some Australian made candidates to consider would be: for the motor. I think they are developing a smaller sized Carbon motor. for the controller. The wavesculptor200 is very compact for what it can do.
The Australian made angle may also be a plus as far as sponsorship is concerned.
Mat B

I got a response from both companies - very nice folks. James (Tritium) got back to me about the Wavesculptor200 and said it will probably run a UQM motor, but not at full power as their controller can't push out much more than 300 phase Amps (UQM's controller pushes out 330). Still, it would extend the useful torque range a bit since it can run at higher voltages.

Bernie (Ultramotive) also got back to me about the Carbon motor. Yes, the motor is 40 kg, but it needs 15 kg worth of inductors to prevent the controller (in this case, a Wavesculptor) from blowing up. Also, the rotor diameter is 402 mm! Huge! Moreover, it is an air cooled motor, which could be a bit of a worry. It requires a nominal system voltage of 450 V too. However, they are working on a smaller motor (the Helium motor) which will be a bit smaller, and more amenable to a motorcycle chassis. I think they should have called it Boron or Beryllium, since there's only one lighter than Helium :lol:
You need to find a way to tuck the motor between the swing arm