perjantai 29. kesäkuuta 2012

Parts list

Parts list for the kWsaki electric motorcycle. I will update this post if I there are changes.
Parts ordered from linked websites where appropriate.

tiistai 26. kesäkuuta 2012


Thanks to an amazingly friendly next door neighbour I now have a garage to work on the motorcycle!

I've also washed the GPX off of all the grease leaked from the petrol engine. That includes crud accumulated by the chain over the years which I won't be unfortunately getting rid of. That's because I've decided on the ME1003 motor along with Alltrax AXE7245 controller from The MHM602 from Enertrac was tempting, but just too expensive as a whole.

I will initially use 18 pcs of small 12 V AGM batteries with are used in UPSes. The should give me a 72 V pack of about 15 Ah or 1 kWh at a weight of 45 kg. Also looking into A123 cells from the EVTV store.

Update! I have now ordered the motor and controller mentioned above. Happy happy joy joy!

lauantai 23. kesäkuuta 2012

Holy wirings, Batman!

Spent a while removing a bunch of now unneccessary wiring and electrical components. Also deepened my hate towards electrical tape which turns into nasty sticky mess quite fast. I'll probably remove most if not all of it and use some spiral wire wrap instead when putting everything back together. I could have removed even more wires, but decided to spare some in case I could use some of the leads and connectors for controlling the electronics later.

I've also pretty much abandoned the 18650 battery idea due to enclosure challenges and also low C rating of the cells. 10 A just go too far without many many cells in parallel. Instead trying to decide between prismatics from CALB or Thundersky and cylindrical cells from Headway. We'll see. In any case the initial installation will probably use old UPS AGM batteries as originally planned.

Also still mulling over the motor. The Enertrac MHM602 is quite tempting. No chain would be lovely. On the other hand, ME0709 is cheap and ME1003 gives almost the same power while still being cheaper than MHM602, albeit more expensive than ME0709. Waiting for reply on my latest inquiry form Enertrac to see if it would make sense to get the rim and spokes locally.

torstai 21. kesäkuuta 2012

ICE free!

It is done. The engine has been removed. All 68 kg of it. Previously removed exhaust pipes and mufflers have been weighed at 9 kg. The rest of the junk in a big plastic box came in at 15 kg. That gives me 92 kg to play with. Not including the liquids which would have weighted 15-20 kg. In total we're looking at more than 100 kg which should be plently for a motor and a lot of batteries. Hooray!

There you have the compulsory ICE free shot. With the addition of the seat the scale was tilted 39 kg in the front and 49 kg in the back. The rest of it will be the fairings and the metal tank which I may or may not eventually do something about. I'll close this with a shot of the never ending versatility of the Ikea bag.

Yes, you can carry a 68 kg engine in it without breaking the bag.

maanantai 18. kesäkuuta 2012

It is on

Looks like I couldn't wait. Instead I spent four hours yesterday taking the bike apart. The picture isn't very good I'm afraid, but I think you can still see the results below. Couple of things came to mind. A) I will never again buy a faired motorcycle. B) I will never again buy a liquid cooled motorcycle. Unless you've actually done this youself it's probably quite impossible to imagine the trouble you need to go thru with those fairings, but the real source of agony lies in the liquids. Needless to say there was all kinds of goo coming out of all kinds of places. Getting the engine oil our from below was easy, but it also came out of the oil cooler and then there was the actual cooling liquid coming from the radiator, pipes, so on and so forth. As if that wouldn't have been enough the clutch was also hydraulic. More gooey liquid. Boy, oh boy, do these internal combustion engines take a boatload of stuff to function.

I'll try to take a good picture of all the crap that came off yesterday. It's a considerable heap already. Actually the only thing left is the main engine block. I might have to wait on that for a couple of days though. Or not. We'll see. Meanwhile you can look at the picture below. Now if I was inclined to fix the ICE on this one I might be somewhat curious on the whereabout of the missing bolt there...

ps. Latest change of plans in the battery deparment involves these 15 Ah cells from Headway. The NCR18650As are tempting, but it may not be a good idea to put many of them in series after all.

sunnuntai 17. kesäkuuta 2012

Picked up and batteries

Yesterday I took the long way home and got the bike. It's sitting outside in the trailer and just waiting to get the ICE out. The weather is getting better again as well after the rain pour yesterday which would make a nice environment for stripping parts out if it lasts. Let's hope so.

As for the battery part of the post I just finished watching the latest episode of EVTV and became highly intrigued of the 18650 battery cells. They are small AA-like lithium cells of the usual lithium voltage and about 3 Ah of power which makes for about 11 Wh per cell. The interesting bit is that you can get them with integrated protection circuitry which protects the cell from over charge, discharge and current. What that means is no BMS which I'm more and more decided upon on not having. Keep it simple, stupid, as they say and simple is also elegant. Elegant is what I like. Less is more. And so on. Anywho. Panasonic has a nice cell in this form factor which can give about 3 C or 10 A which would probably be enough for me. The math is 72 V motor means about 24 18650s at 10 A each totaling 240 A pairing to a 300 A controller and we're quite close in the numbers. This would also give me a way to get started on the cheap by way of buying just those 24 18650s to get a 72 V * 3 Ah or 0.2 kWh pack, see how that goes and just order more if it's all good.

Next up is taking the bike back from Espoo to home to Pori where it will probably spend the rest of it's life or at least lithium air batteries become viable and there's enough juice to drive around the country.

ps. Updated my EV album page at with current plans.

ps2. After thinking about it for a moment 24 tiny cells in series all by themselves might be a bit much. It's probably better to make a "6s4s4p" combination. That would be six packs of 4s4p in series. 4s4p being four cells in series and four cells in parallel. This would take 96 cells and result would be 72 V 12 Ah 0.864 kWh pack (or about 1 kWh if you count with 3.7 V per cell). These NCR18650As with protection look to be about $6.5 per cell so ordering 100 cells would be $650 and leave some for spares. As a bonus the 4s4p modules could be charged with a 12 V charger. Nice.

torstai 14. kesäkuuta 2012

Pick up date

No, this isn't about dating. I've made an appointment to bring the new baby home. Or at least pick it up on Sunday. After that I will be hauling it back and forth in a trailer before finally taking it to it's destination. Nevertheless I am feeling happy about having a date set and I'll be even happier when I have the bike at my disposal. Just so that I can sneak out and go pet it ever so gently if I so please.

I've also been wooing some sponsors. So far I've been sort of promised some help in manufacturing mounts and hopefully there will be some good news from another lead tomorrow. I'm not getting my hopes up, but it wouldn't hurt.

Perhaps I'll go right ahead and put up the first sponsor logo up here.

keskiviikko 13. kesäkuuta 2012

It's a whole new kWsaki

I guess it's always the One More Thing that ends up being the most important one. At least in this case. As it happens I now own another Kawasaki product. It's a 1987 GPX750R and it looks like this:

Timing chain had snapped while the engine had been idling - with predictable results. Or at least that's how the story goes. I couldn't care less since it has working 12 volt system, brakes and it's registered. Most imporantly it's now mine and I only had to pay 500€ for it. The new body seems a lot more aerodynamic than the naked figure of the Z500 so I'm at least hoping for a few more miles on a charge. In any case next up is dismantling the engine. Let the good times roll.

ps. I'll be selling the extra engine parts from this one as well so let me know if you need anything.
pps. Parts for sale at Finnish website here.

maanantai 11. kesäkuuta 2012

Mulling over

I'm mulling over the options one of which is the motor. I've pretty much settled on the ME1003 actually. Usually when there are two options and you know which one is the better, but you end up choosing the other one just because it's cheaper you also end up thinking you should have gone with the better option. You also know you'll be stuck with what you got because you can't afford to buy a whole new set anyway. In this case better motor comes with a more capable controller and probably a sturdier contactor as well. Controllers are also a significant portion of the cost. Less so with the brush type motors, more with brushless, but a portion none the less.

In an ideal world I wouldn't actually be making my pick between these two motors at all. If money was of no concern I'd definitelty go with the MHM602 from Enertrac. It's a beautiful, brushless hub motor meant for motorcycle conversion and it can deliver around 10 kW continuous and 30 kW peak. Being brushless and beautiful does come with a price tag to match, as usual. As if it was not enough that the motor itself is twice as expensive as the brush type motors it also requires a more expensive controller. All this adds up to a price tag of around $2600 for the kit with shipping as opposed to the $1000-1500 of the brushed, chain driven counterparts. Of course you'd win back some not having to by sprockets and chain, but nowhere near a grand. You would however have more space for batteries and no chain at all, which is why the hub motor would be so beautiful. What I have is an hate-hate relationship with chains. I don't like them and they don't... Well, they don't really have emotions, but I'm quite sure if they did they'd hate me back.

A friend of mine asked me to write about the weight issue. I don't have anything to properly weigh the bike as it is, but thanks to the wonderful world of Google (previously known as the Internet) I found out you should be able to use an ordinary bathroom scale to do the weighing by adding up the results from the front and rear wheel. Whatever education I've had might also have attempted ingraining this knowledge into my brain, but Google is a lot better at indexing stuff than my little grey cells. So off I went with an Ikea Bolmen bathroom scale and measured the bike. The Bolmen is a horribly inaccurate little scale, but it looks sturdy, is very cheap at less than five euros and goes up to 120 kg. The registration of the bike indicates that the curb weight should be 210 kg, so you can imagine my amazement when the front wheel read 100 kg and the rear wheel 110 kg. Exactly as the gods intended. I now had a semi-reliable method of weighing the bike and an idea of the weight distribution with no driver in the saddle.

Based on what I've been able to gather the weight of the 500 cc internal combustion engine currently propelling the motorcycle could be around 50 kg. The ME1003 motor and associated electrical parts should be around 20 kg. The battery I'm planning to use in Phases One and Two will weigh 20 kg as well. What I call Phase One is replacing the ICE with the electric motor and AGM batteries. Phase Two will come after the inspection of the bike and entail swapping the AGM batteries to LiFePO4. The AGM and lithium packs will be similar in size, weight and voltage, with the lithium version eventually packing a lot more punch than the ancient battery chemistry. In any case the electrical parts should weight less than the smelly dinosaur powered noise generator. With AGM the range will be abysmal and performance severely limited. Phase Two lithium pack should improve both performance and range, but I'm still not hoping more than 30 km on a charge. Enough for a bit of cruising around town, but not much more. Phase Three and all phases after that should gradually improve the range in approximately 20-30 km increments via new battery pack connected in parallel.

Funny how things add up and end up being in such harmony. Partially by design, but also by mere coincidence each phase ends up costing about 1000€. In Phase One this will be the cost of the motor kit, in Phase Two the 20 Ah 72 V 20 kg LiFePO4 pack, Phase Three the second 20 Ah 72 V 20 kg pack and so on for all the future phases until the bike gets too heavy or a new battery chemistry becomes viable. Each Phase will also weigh around 20 kg. Granted, Phase One will actually by 40 kg, but half of it is the AGM pack that will be replaced in Phase Two with as much lithium based storage. I also cut another corner in Phase One pricing - the import taxes will probably raise the total price and I still have the charger issue unsolved, but I believe you can still see the 1000€ per 20 kg per Phase harmony here. At least I can and I find it highly satisfying.

Oh. One more thing. Another big issue to mull over is the bike itself. It may also end up being a completely different bike that gets converted if a suitable rolling chassis ends up rolling my way. I may have to limit myself to Kawasakis though. It wouldn't be a kWsaki anymore if it was a Suzuki...

perjantai 8. kesäkuuta 2012

Recipe for an electric motorcycle

Take one old motorcycle with a lot of miles on it. Preferably something that leaks a bit of oil, has trouble running when wet, clutch is slipping, tank contains more rust than gasoline and so on. In other words something like this Kawasaki Z500 -81 - only three years younger than your's truly:

Next order a conversion kit or separate electrical parts from your favorite online EV supplier. This is the part where I am currently at. I have pretty much decided on a 72 volt system with a brush type DC motor. The motor will probably be either ME0709 or ME1003 mainly depending on how much money I'm willing to spend. The batteries will initially be old UPS AGM type, but if all goes well and the bike passes the Finnish equivalent of MOT test after conversion I should be switching to LiFePO4 as soon as possible. This will also require a proper charger. I am planning to forego BMS completely and instead relay on the bottom balancing method as described on EVTV on numerous occasions.

ps. Let me know if you'd like to buy the engine. It's actually in a pretty good shape.