Hmm, all this stuff about WMI's and VINs. About mules and gliders. Aren't we missing something? Oh that's right - our customers want to buy an all electric maxi-scooter with the quality of a Vectrix but the price of a Chinese import. Heck at least we sure hope you do!! So without further ado the heavy lifting part of the project begins. Now is the time where the rubber hits the road - or in our case the TIG hits the metal.
At this point EVMFG grew to include Terry. Terry is great. Terry is lord and master of all things welded or otherwise fabricated. In fact we wanted to put that on his business card - but we chickened out. Instead he's Director of Product Development. Fancy titles aside we're very happy Terry joined our team. He has aorund 20 years of experience in the EV world. In the late eighties he was working for a company that converted VW Rabbits from gas to electric. They were the only manufacturer to crash test their conversion. This was the time of the Carter Administration and big utility companies were buying these conversions - whether that was for PR or for operational value is somewhat questionable. Terry is the first to describe how "his" cars used to turn up at various shows and other PR events. At the end of the day the battery technology for a viable commercial conversion just weren't available - flooded lead acid was too heavy and too finicky. Fast forward to the end of Terry's career and one of his last jobs for Chrysler before retiring was to travel to Spain to help Tata engineers convert small utility trucks to all electric for the 2008 World Fair in Barcelona. While at Chrysler Terry also worked on the GEM and various other electric products - none of which ever seemed to reach their full potential. As I said in a previous post - the car companies have the talent and the resources to build the best possible EVs. Don't ask me why they don't - I don't believe most of the reasons they give anyway.
Probably the most important, and challenging, aspect of the bikes design is the new swing arm. In original ICE form the engine and transmission actually form the swing arm. (The swing arm is the rear part of the frame that pivots and carries the rear wheel). On the ICE bike the pivot point is way up high - this is "unusual" to say the least. With such a high mount point under acceleration the rear wheel has the tendency to want to push up on that point causing the bike to rise. Probably not a very big problem with a 150cc gas engine. But with a high torque electric motor we needed to come up with a better mounting point 
Our swing arm mount is low down and it's substantial design is over-engineered to carry the stresses involved. However, this is one of the key areas on the bike - you wouldn't want us to skimp there. Believe us you wouldn't want that - and believe us we didn't. Into those mount points goes the swing arm itself. Again this item is designed for strength - not beauty (but, hey, I think it's beautiful too!) 
The photos you see here are early working models. For example there are three mounting points for the rear suspension to allow for different geometries to be tested. The production version will have a single mounting point with a bushing. 
On the electrical side we've mounted the controller and current DC-DC converter in the tail of the bike - one each side. In production we are likely going to transition to a higher quality (and higher cost) Vicor DC/DC converter. As well as increasing the reliability of the bike this will allow us to consider a permanently mounted charger rather than a portable design. Heat is the main villain when it comes to failing electronics - care is taken to make sure we have sufficient airflow to keep these components in spec. Whichever DC-DC converter we use it will have best in class power output. We will use a 13.8V output meaning bright lights (a lot of bikes use a strict 12V which is less than the voltage usually seen on an ICE model). We will also have around 200W constant (and 275W peak) power capability - that's about enough to run a heated vest in the winter!
If we transition to the Vicor DC/DC we will likely be able to permanently mount the charger which is a good convenience feature especially because we won't sacrfice cargo space to do so.
Our first model year bikes will come with a 300A Kelly Controller and a seperate BMS (battery management system) based on an open-source design. We are also implementing an additional "meta-controller" (a controller for the controller). We call this the BCU (Bike Control Unit) it receives its inputs from the BMS, from the battery pack and from the motor. With this information we have implemented a "proper" fuel gauge - we monitor the Amp Hours used by the bike rather than having the rider trying to "guess" the state of charge from a simple volt meter. Furthermore we use the BCU to control the regen braking function. By tying into the brake light switch we know as soon as either brake is applied, at that point (which occurs before the brakes begin to engage) we engage the regen braking mode of the controller. We start off with a low amount of regen and then begin to ramp up with more regeneration braking force. As well as controlling braking and fuel guage the BCU is used to record speed and usage statistics.
For the technically adventurous owner we will provide details of how to interface the BCU to a digital dashboard. Our first models use a traditional speedometer and fuel gauge. This gives a nice clean and familiar "user interface" to the bike - but if you want to go with a more modern LCD dashboard approach - be our guests!
In time we expect to replace the Kelly controller and seperate BMS and BCU with an integrated design that incorporates all three functions. With tighter integration between these three we will be able to offer more features. But early adopters won't be left out in the cold - any time we improve our bike the changes will be backward compatible and easily retro-fitted to pre-existing bikes.
So that's a brief view inside our process and how we went about building our bike.
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