New Project: BikeE E2 Dual 20 Tandem Recumbent

Greetings!
A new year, a new recumbent project! One of my dreams has been to own a tandem Recumbent, to ride together with my sons or wife. My wife and I actually tried a tandem recumbent at Gardner Martin's Easy Racer facility in Freedom CA, where Gardner personally helped us ride their offering (yes, it was that long ago)! I was hooked, but circumstances (read: money) dictated that it wasn't going to happen any time soon...

Until last month! I picked up this beauty in Northern California - a BikeE E2 Tandem Recumbent, in very good shape, with many unusual upgrades:

- This E2 has been converted to a 20/20 configuration - clearly the way it should have come out of the factory. The 16 never had a good history on this bike as a heavily loaded tandem. Not only is the front wheel a 20 inch, but it also includes a front suspension, which turns the bike into a fully suspended configuration.
It looks a lot like a Barcroft Columbia except cooler. Higher captain step over, but totally worth it.

- The rear wheel has been replaced with a NuVinci Enviolo 360 CVT hub. This thing is an incredible breakthrough in shifting for bicycles, and I can't say enough good things about it. CVT stands for "Continuously Variable Transmission" - through a combination of large bearings and belts, it essentially offers unlimited gear ratios (it's a similar design to that offered on today's Hybrid cars). Super cool, tech geek stuff - and it really works.

- The frame is a massive monocoque aluminum girder, strong and cool looking. While you can see from the picture that this bike is long, I believe it is actually the shortest tandem recumbent ever offered. When riding it single, it doesn't feel that ponderous - but it is heavy. I would guess it's over 50lbs, and probably closer to 60. As the "Worlds Longest short wheelbase", it actually feels rather agile.

- This bike came with tire DOGS, the Maxxis Hookworms. I replaced them with a terrific tire set of a racing Tioga Power Block 20x1.95 in front, and a Tioga Street Block 20x2.15 100psi in the rear. Transforms the bike to make it MUCH faster with significantly better rolling resistance and ride. Before the swap, it felt like the bike had been dipped in molasses. These tires are seriously fast, and I must shout out the Street Block - it looks like the Power Block, but has been significantly strengthened (100psi), and is fast, good looking and bomb proof. Same tread pattern, much tougher.

- The BikeE seats are notoriously comfortable.

Still working on more, effective upgrades, but today was Show Day - I featured this bike in my engineering lesson at school, it was a total recumbent geek fest...

Its nickname is "Godzilla", as it is truly King of the Monsters!

 

Question: what tires did you use on the Screamer? I find this tandem to be extremely sensitive to the quality of tire - the wrong tire and it's a sluggish nightmare...

 

I tried the Bike-E E2 at a bike show shortly after it was introduced. I managed to ride it with some difficulty, but my buddy couldn't do it except solo. The steering geometry was just too weird. At the time I dubbed it the worst-handling recumbent ever marketed and predicted that lawsuits over it would decimate the company. You 20" conversion looks like it results in a 0-raked fork, which may actually make it rideable; but it looks like it's retained the 16" fork legs?

 

Yup, I received it with a rather hokey front solution. The previous owner reversed the 16" forks, and inserted INSIDE of it a 20 inch suspension fork. He then drilled a bolt hole through the bottom of the fork and head, and screwed them together. They fit tightly, with no wiggle, but "no warranty." The E2 head is a nonstandard, LARGE size, (1) I can't find a suspension, or any, fork that will fit, and (2) the current suspension fork slide perfectly inside without wiggle or slop. This bike should have been a 20 inch from the get go, I don't understand why they went with the 16. Still, this is a hokey solution, and I'm working on a better solution. Still, it works at the moment.

 

The original fork WAS 'backwards' to supply some trail, due to the 0 degree steerer tube. Going to a 20" front wheel would result in a change in the steerer angle and some small amount of trail using a zero-offset fork.

 

Ah, the legendary Tioga Comp Pool, perhaps the best 20 inch slick ever made! You can't get your hands on those any more, too bad...

 

Update: First, I have finally found online instructions to convert a BikeE 1 1/4" headset (huge!) to a standard (1 1/8") front suspension fork! I'll be implementing it this week - FYI here is the link:
https://www.plunk.org/eben/Albums/BikeE/

Second: I have embarked on the bike transformation of a lifetime - converting Godzilla to an electric bike! The end goal will be a recumbent Truck EV, but we are almost done with the EV conversion part... check out the cool picture (p.s. the CVT is on the left):

 

Another exciting update for Godzilla! I was able to follow online instructions I found to rebuild the front wheel assembly for a clean 20 inch/ 406mm full suspension! All the hokey bits have been removed; I purchased a set of 1 1/4 to 1 1/8th shims from AliExpress to allow Godzilla to accept an RST/Capa 1 1/8th full front suspension unit. Check out the pictures - it's professionally installed by Walt's Cycle in Sunnyvale and I rode it home this afternoon... almost there!


p.s. here's the link to the instructions and parts list on the 20 inch front suspension conversion:
https://www.plunk.org/eben/Albums/BikeE/

 

Godzilla EV Conversion nearly complete! Wound up taking about two months and a LOT of custom engineering!
1. Removed the stoker handlebars, cut off the adapter portions, and my HW engineer created a custom adapter to mount the EV motor. Version 1 was aluminum and failed on the first test! I guess Aluminum isn't as strong as steel. V2 was steel! Works great.
2. EV motor is 375 watts, so perhaps it's more technically "EV assist". V1 Throttle is from a electric scooter, the OEM thumb throttle has both motor control and LED battery display, coming soon...
2.1 EV motor was wired BACKWARD from our planned install! so we had to reverse the motor polarity (easy) and acquire a LEFT rotating motor sprocket instead of the RIGHT rotating sprocket which came from the factory (hard). Fortunately my team of engineers (the guys responsible for Discovery Channel Battlebots Champion Tantrum!) were up to the Challenge, and you'll notice the motor is facing the LEFT side, unlike the earlier picture. This also allowed for easily adding a second chain sprocket on the LEFT side (in Black) to drive the system at the appropriate power levels, and without interference from any of the (multiple!) existing chains.
3. This is a 36 volt system, the battery should yield 50-70 miles of assist. The kit was $59.95 on Amazon.
4. The only things remaining are replacing the stoker seat with a truck bed (using the mount/adapter), install the OEM throttle with battery LEDs, and upgrading the lame rear suspension unit with a more modern component. We are also 3D printing a complete unit to house the battery, controller and wiring (if you look closely, this prototype is two separate 3D printed units...).
We are ALMOST THERE!!! I think this is the way the original BikeE E2 should have been designed.

 

Godzilla v1.0 is COMPLETE! Final updates to Godzilla are...

(1) Kept getting flats on the front Tioga PowerBlock 20x1.95. Traded to their best BMX park tire, the 20x2.25 Tioga Spectr. Smokin' fast, 120tpi, 100psi, bulletproof liner, extremely low rolling resistance for such a beast, fit perfectly, worked perfectly.

(2) This monster weighs 65+ pounds fully loaded! (not including rider!) Sooo a new, wider 36 spoke front wheel was needed. I picked up a 20 inch Wheel Master unit with a 19mm wide Weinman 519 aluminum rim. Minor problem was, the wheel bearings came dry! An hour later, after hand packing the bearings with automotive lithium lube, they spun like crazy. Looks good, runs even better.

(3) My nickname is "Lucky Larry", and I just keep getting lucky! It turns out the original owner gave me a perfect/ almost new Cane Creek AD-5 rear air shock unit, which was undiscovered in the bag of extra parts he gave me at purchase! I stumbled across it and immediately installed it on the rear. Cane Creek air shocks are magical Cadillac units, which, when properly inflated, yield a silky, refined, controlled ride. And were originally very expensive. So Godzilla's rear end is both tight and soft...!

(4) While the electric conversion engineering is solid, I woefully overestimated my range from the 36v 10 amp battery. With a 65lb bike and a 375watt electric motor, the proper analysis yields closer to 20 miles on a charge. Which I found out the hard way on my first 20 mile ride attempt with a half charged battery (plus an unadjusted rear brake drag). Halfway out on the ride, the battery died (!) and I went from a 15mph average to about 6mph average, using only my "bioelectric battery" (me) to get home. Fun and Easy out turned in to not quite so fun and not quite so easy back! Still a good lesson, and I'll probably pick up a backup battery for longer rides!

(5) The cheesy electric scooter throttle is cheap and difficult to hold steady, last real update for v1.0 will be to swap that unit for the OEM thumb throttle, which is a much more advanced unit, and includes battery charge LED lights to keep an eye on what's left.

(6) Interestingly, Godzilla presents as a 100% Battery Assist bike. The pedals are locked step with the motor under load, so you have to pedal combined with modulating the throttle to get anywhere. Still, the feeling is simply super easy pedaling! And with the EV motor off, you can coast... Another interesting artifact is that, under EV load, the Nuvolo CVT transmission will not shift. Apparently the EV motor torque locks up the CVT internals. So accelerating is basically like riding a Godzilla motorcycle - Throttle up/pedal, then lift EV throttle, select a higher CVT ratio, then back on the throttle/pedals.

For better and worse, this monster LIVES and RUNS RIGHT NOW - Woohoo! V2 will include the truck bed, but for now, she is road worthy and I can bungee cord a plastic milk crate to the rear seat for any shipping needs (including my dog Princess!) Biggest, Best, Baddest home engineering project I've ever undertaken! Kudos to David Mintz and the Battlebots Tantrum Team, and Walt's Bike Shop in Sunnyvale for the engineering and execution assistance! I'll try and post a video ride soon... Godzilla LIVES!

 

One more picture update:
- a strange artifact of the poor handling inherent in all BikeE E2s is that the handlebars are simply too narrow. They make it more difficult to get the exact amount of angular rotation needed to stay completely stable. Even though the dual 20s on Godzilla substantially increase the steering stability, it's still a bit edgy. I looked for, but could not find, handlebar extenders which would fit on these so I tried another engineering twist - I cut two inches off each side of the handlebar grips! My 5 inch grips had 5 one inch segments, so I cut two segments off, yielding another 4 inches wider between my hands. My hands now permanently rest on the grip shifters, but I naturally do that anyway for most of my ride, so it feels fine. And the extra 4 inches of distance between my hands contributed greatly to the positioning of the front wheel, and noticeably increased steering stability, much better than before. Here's an odd picture of the new setup...
With this configuration, I blew my PR for my regular ride out of the water! This bike is Big, fast and scary!
p.s. gotta have two mirrors on this Bad Boy! And a super Bell…

 

Godzilla update: (1) it turns out the reason the old owner wasn't using the Cane Creek AD4 shock was because it leaked! One of the seals was bad so it would only hold air for a day. So I went back to the color matching (pink!) RST 56 fluid rear shock - it works fine here and looks cool...
(2) I got a super cool Godzilla sticker.. in pink! As it turns out, in the latest movie, Godzilla's OP power color is pink! We were ready for that. (3) I used bike acrylic to paint the rear swing arms black so they would match the new front RST/Capa black shock. I like it.

*** Cool *** Godzilla was accepted to show at the San Francisco ElectrifyExpo, North America's largest EV vehicle conference! If you happen to be in SF for Aug 24-25, drop by and say hi, we'll be in the Electrify Showoff, should be fun.

 

Amazing Moment: Godzilla has been selected to compete in the ElectrifyExpo SF Showcase for "Custom EV Bike Design"! ElectrifyExpo SF is the largest EV show in North America, and we are honored to represent on behalf of recumbents everywhere! I even learned how to weld creating our last custom piece - a kickstand! The OEM unit no longer fit the bike because of the CVT, so we customized it - it's now a Godzilla foot! We'll keep y'all posted, as the show is this weekend!