Electric Motorcycle Concept - Djuka Cruiser

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. :unamused: :wink: 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.” :wink: ) 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! :slight_smile: 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!


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Wow, massive project. I like the style. Do you have any development material? Would be cool to see the entire process.

Just a few Q’s. Is there any particular reason why the fron suspension goes all the way up to the handlebar? The leafs makes it a bit confusing to me. Would it be possible to move the leafs tighter together and still have the same function, like you did in the rear. Maybe a shorter distance between the four of them. Dont think it would be as interesting to look at if you made it exactly the way as in the rear, even if that is also a nice detail. Food for thought :smiley:


The seating looks a bit underdeveloped / weird. It’s a visually very heavy bike, and the seating looks very crude and not very welcoming.
Id probably redo the front light. aesthetically its not close to the rest of the bike, like a catalogue lamp on a totally custom bike.

Last thought is just a minor minor detail. Id like to se a bit more work on the end pieces on the four cornered tube on the rear suspension. A nice way to end them off instead of just cutting them there, to make it a tad more sophisticated.

Cool project!

Bravo! nice work and great to see somebody doing their homework about how all the bits work together. I agree on the headlight, and as to the seat offer a range of style or service to personalize to riders choice. The front fork emulating the old springer is fine, just wondering how the carbon will hold up over time, you might want to sneak in a few spring steel ones just to be safe.

Excellent project, admire anybody that commits so much time and shows their results.

I think you’re correct that no one is addressing the older rider with new design bikes. Harley Davidson, Yamaha and Honda continue to put out massive machines with a few token updates.

Overall, I’m not completely fond of the blend of sharp rectilinear and soft arc-curved design details, i.e. the main body is all sharp lines and angles, the front strut is a beautiful long arc.

That’s alot of linear welds on aluminum. Every sheet metal shop I’ve dealt with has refused lengthy welds in aluminum or aluminum assemblies with lots of welding. Could the frame parts be partially formed and then welded or bolted? Drives part cost down.

Great effort designing and modeling the bike! There are some electric cruisers in market, though not high power/volume. Your style reminds me of http://www.confederate.com/splash10/.
As always, there are room for improvements. Functional details should be improvised- front and rear suspension, chain drive, and frame that holds the rear wheel (structurally weak points).