Motorcycles

RMK E2 update highlights exposed wiring around that badass hubless rear-wheel drive

RMK E2 update highlights expos...
The RMK E2 should be ready for limited production runs in 2019
The RMK E2 should be ready for limited production runs in 2019
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RMK E2: hubless rear drive looking badass with those exposed wires
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RMK E2: hubless rear drive looking badass with those exposed wires
RMK E2: updated renders
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RMK E2: updated renders
RMK E2: streetfighter bars change the look toward the hooligan end of the spectrum
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RMK E2: streetfighter bars change the look toward the hooligan end of the spectrum
The RMK E2 should be ready for limited production runs in 2019
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The RMK E2 should be ready for limited production runs in 2019
Chunky triple clamps and forks
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Chunky triple clamps and forks
A glimpse at the battery box from under the bike's headstem
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A glimpse at the battery box from under the bike's headstem
Bodywork under construction
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Bodywork under construction
The E2 in prototype format, under construction
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The E2 in prototype format, under construction
Tail section under construction
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Tail section under construction
Looking down on the "tank" with the bike still under construction
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Looking down on the "tank" with the bike still under construction
A peek under the top of the battery box
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A peek under the top of the battery box

We've just received some new renders of the upcoming RMK E2, a quick electric motorcycle with a range up to 180 miles (300 km), peak power of 67 hp (50 kW), and an attention-grabbing hubless rear wheel. There are a few behind-the-scenes shots too, as the RMK team builds the first prototype.

RMK's Head Designer Teemu Saukkio got in touch from Raisio, about two hours West of Helsinki, Finland, to give us a few updates on where the E2 project stands. The new renders put a raised handlebar on the bike, where the old ones showed clip-ons – this gives it more of a hooligan streetfighter stance as opposed to a café racer.

They also show further detail around the nicely flared tank, and add in what will be a signature design stroke: beefy exposed wiring from the back of the battery box that curves around and into the hubless rear-wheel drive system. A lovely touch for those who get excited about cable routing – and there are more of those guys than you might think.

RMK E2: hubless rear drive looking badass with those exposed wires
RMK E2: hubless rear drive looking badass with those exposed wires

The only problem we can see is that you're probably going to need some protection on that wiring, particularly where stones might flick up from the front wheel. The last thing you want is to be exposing any copper to the elements.

While we're at it, let's take a look at the E2 prototype under construction. Here's a nice look at the front of the battery box under the headstem, showing the skeleton of the E2's broad chest and a glimpse at the battery pack.

A glimpse at the battery box from under the bike's headstem
A glimpse at the battery box from under the bike's headstem

Saukkio and the RMK team have had to design their own motor for that outrageous rear wheel. Hw tells us it took him "about a month" to study up on electric motor design and come up with the hub drive he wanted. The prototype's apparently coming along well, with testing scheduled to be complete before the next Finnish summer, at which point RMK plans to be ready to build 50 to 150 bikes in 2019, with a view to ramping up in 2020.

The company's already got ten pre-orders on the books, and Saukkio says there's an E3 in development as well. The key challenges, he tells us, will be figuring out how to make the thing legal under EU laws, as well as raising capital to move into volume production.

We look forward to seeing the E2 built, it'll sure be an eye-popper. There's more behind-the-scenes shots in the gallery.

Source: RMK Vehicles

6 comments
Daed Alus
Looks OK'ish, but god knows how it's going to handle with all of that unsprung weight. And the centripetal forces of all that rotating mass will make it hard to lean. Very, very unsure how well it will work in practice.
Nik
Daed Alus; My thoughts also, the unsprung weight, and the gyro effect of that wheel, must be horrendous. I can remember the difference in handling of my bike, when I just changed the steel rims for aluminium. In addition, the effect of hitting a pothole, curb, or other road obstruction, like a 'sleeping policeman' is likely to render the motor instantly (f-)dead! This is strictly a ''posers machine'' is my guess, not even a CSR. [Coffee Shop Racer.]
RXStephen
Yes un-sprung weight will be a problem, although to counter that the weight of the batteries will keep the ratio down. The gyro effect will not be an issue because those motor windings are static. It's an AC motor, so the rotating part will just be a cylinder around that core.
highlandboy
The entire motor is unsprung weight. Just because it doesn’t rotate doesn’t change the effect of the mass being bounced up and down over every pothole. It will stop the wheel giving proper traction on rough surfaces.
Tommo
Yet another Fugly motorcycle. Given the more flexible constraints given by an electrical motor, why oh why do they always have to be so ugly..?
Daed Alus
RXS, you are correct that the coils will be stationary, but there is a substantial rotating mass in the rotor itself plus the bearing which is going to be some 16" in diameter. Even if it is supported by an alloy hub the bearing races still need to be fairly thick to avoid deflections. It's going to heavy.