Thought I’d share my concept electric motorcycle here amongst all you designer-type folks to get some suggestions / recommendations. I should point out that I’m neither designer nor engineer - I just happen to have the hobby of doing 3d work and have a passion for electric vehicles.
The whole thought around this concept was to come up with a design that’s a fusion of old-school chopper/bobber motorcycle looks with modern-day technologies. The vast majority of electric motorcycles that have come out in recent years follow either the crotch-rocket race bike style, your smaller moped styles, and a few off-road/enduro styles - most primarily targeted towards the younger crowd. Nobody has really come out with a design that would appeal to the more traditionalist, old-school bikers out there.
There’s no silly impractical ‘hub-less’ wheels, or some non-existent theoretical ‘whacky’ components involved with this design. It can be built using existing components and materials available today.
I’ve come up with several different ways of approaching how a motorcycle is built. (As much as I’d like to say it, I hate using the word “innovative” any more, as so many ‘concept’ designers use it - and usually it means “totally unrealistic and impractical.” ) The first is the main frame. Whereas the majority of bikes out there use some sort of external, tubular frame, I decided to approach this with a sort of “inside-out” idea - using the i-beam concept. As you can see with these first renderings, basically you’ve got a single sheet of 1/4" aluminum with cutouts and 3" wide 14" plating welded along the perimeter. All of the internal cutouts are reinforced by the component 'shelves - made from 1/8" aluminum plate.
Regarding the ‘component pods,’ each has a specific use. Starting from the top down, the ‘tank’ holds the motor controllers, contactors, fuses, etc. The second ‘pod’ contains the battery chargers and the Battery Management Systems (BMS) - which keeps the cells balanced and operating at their optimal levels. The lower two pods contain the battery cells themselves. This particular design is based around the 3.3V 10AH cylindrical cells - combined to provide 60 Volts with 60 Amp Hours (60) - or a total of 3.6 kilowatt hours.
The smaller compartment under the seat would contain additional fuses, and heavy-duty Schottky diodes (isolating the various battery packs from each other while charging, while at the same time allowing them to be connected in parallel).
Lastly, the triangular cutout houses the motors. In this case, I am utilizing two, 12KW motors, using a single stage reduction, two speed gearbox. Though generally one does not need multiple gears in EVs, motors do have an upper RPM limit (primarily due to heat buildup). So, while multiple gears are not necessary, having them can be useful so that the motors are operating at their optimum RPM based on the driving environment (city vs highway speeds).
The rear suspension is also unique in two ways. First, rather that the traditional swingarm, here I’ve borrowed the double-wishbone system typically seen in the front suspension’s of performance cars. The main purpose of this is the ability to place the driving sprocket at the pivot point of the arms - thus eliminating and chain slack seen with traditional swingarm setups. The second ‘innovation’ is the use of carbon fiber ‘springs’ - which double as the rear fender - in lieu of traditional hydraulic/spring shock absorbers. Again, this concept is borrowed from old-school, leaf spring suspensions found on the front forks of older motorcycles.
The front suspension system also borrows on several old-school designs: part girder, part springer, part leaf-spring. Again, here I’ve used carbon fiber leaves (pre-formed with a downward curve - as with the rear fender/spring).
And there you ahve it! Still need to do a lot more work with it, but for the most part, things seem to be falling into place nicely.
Anyway, any comments or recommendations will be welcome!