High performance & durability Cannondale Semi Recumbent

The grin wire is cool but i have miles of 12 gauge here... :)

Anyway i wired and spun up the motor.. it hit 1035rpm on 48.1v... holy smokes, batman! That's 21.51kV!
The bad news is that this motor will be a horrendous amp chugger to get started, which means my 7P em3ev battery will not be adequate ( it was already on the border of not being adequate )

The good news is that this hub will do 45mph on 50.4v without aerodynamic aids. With aero optimizations, we're looking at up to 50mph.

On another note, 7 months of not riding bikes, plus just enough bone density resulted in me taking a 32.5 mile ride without a motor today just to test the limits of my new legs. The really good news is that when i managed to tire out my left leg, i was able to compensate by putting more power on the right, and surprisingly, it didn't hurt.

One really interesting thing is that i assumed a normal pedal position. Whent i had tibial torsion, i used to push with my heels, now it's moreso forefoot, like everyone else does. I can exert more power this way. I just naturally did this without even thinking.

Same thing with my back. I stand taller now, with a totally different posture. It happened automatically. I also taught the right leg to walk correctly without any guidance. This makes me question the value of all the physical therapy i went through before i had this..

Enough about the rider though :lol:

The bike is waiting on a 9 speed freewheel and battery before it gets the motor back on. Hopefully it is not scorching hot by the time i get the components!
 
This is all really cool, especially how your coordination naturally adjusted to the position that worked best. It's like you're a human now! :p

With the 3T, you think limiting battery current will reduce forward thrust that much compared to the current/thrust levels you would be running with a 4T?
 
thundercamel said:
With the 3T, you think limiting battery current will reduce forward thrust that much compared to the current/thrust levels you would be running with a 4T?
Click to expand...

The 3T in a 20" wheel versus the 4T in a 26" wheel is still ~12% faster, which is a big problem. I used to run 48v 80A on the leaf 4t in a 26", and it gave excellent acceleration. On 60A, acceleration was ok but a bit weak. This is a job for RC Lipo if i've ever seen one.

The smallest moped tire for a 16 inch wheel that isn't garbage is 16 x 2.25. Apparently 18" bike rims do not fit 14" moto wheels. Basically i cannot run smaller moped/scooter wheels without the help of a very exotic wheel build. Such a wheel build would fix my "too high kV" issue though.

Another 5P of the super high density Samsung 35E's would make for 40ah 50.4v or 2kwhrs, and will drive this amp hungry beast in the current size wheel. But i need to save up a little cash before i can get there..

Looks like i'll be running the eZee with phase timing advance and the big 16 x 2.5" tire, for a top speed of 35mph. Adequate for most roads, but is a super inefficient motor. However, it'll work for now.
 
I get the 50.4v 23.8ah battery early next week. Things should be up and spinning soon. We'll see how much the eZee motor likes running on 2250w peak; currently i've only been shoving 1400w into it.. :twisted:
 
Don't worry, i have a video coming up! My leg is doing great and i'm up and moving and building stuff :bigthumb:
 
[youtube]tUqKtVpzMmI[/youtube]

Skip to 9:05 if you just wanna hear about the bike and skip the story about me learning to walk again from the surgery.
Summary: i taught myself how to walk, have been riding a pedal bike, built a little 'trunk' for the recumbent, have a motor and battery to mount, etc.
 
I've been busy trying to figure out what to do with the "too fast a winding" issue.

First thought.. let's go down one rim size and go a 15 inch scooter/moped wheel.. well, tires in that size are usually wide and knobby, and there's a very limited choice, so forget that..

14 inch? seems to be a common scooter size. Lots of nice 2.25" wide tires with street treads in 14". Myron's mopeds says that 18 inch bicycle rims and 14 inch scooter tires do not fit though, which is soul crushing. I can't seem to find a 36 hole scooter/moped/motorcycle rim in a 14 inch size.

Seems that the only sane route is to stick with the 20 inch wheel and throw more amps at 'er. 75A at the least.

I spose in the meantime, i'll play around with the bafang G310 on another bike.
 
Just got back from my nightly ride, and i found a couple cheap 20 inch tires, so i followed through on amberwolf's idea and made a Tire in a Tire. The resulting "tire" weighed 1.7lbs, compared to the lightest of my scooter/moped tires, the Hutchinson Spherus at 2.7lb.

The resulting tire in a tire rolled notably faster than the spherus, despite the fact that the outer tire is a cheap shitty CST with a funky thread. The total tread depth is 8mm, which is 1mm more rubber than the Marathon Plus. So in theory, my bike could be sitting on 10mm of rubber if i combined a Marathon Plus with a lesser tire. :idea: :thumb:

I was also at my local bike collective and picked up what looks like a completely working rust free 2706/2806 in a 26" wheel for $50, with 0.35mm lams. According to the simulator, this motor would hit 34mph on my battery. Hmm.. ( the bike can take a 26" tire/wheel.. )

I'm going to try this Tire in Tire business on the bike during the next week; because maybe i can get away with running the big 3T motor in a 18" bike wheel with bike tires, if i can find one that's made with any quality. Iron losses start to be a factor because of the 0.35mm lams, but god damn if it won't fly up a hill!
 
I rode through the industrial part of town, whose roads are full of crap, and the tire in a tire survived :thumb:
Shout out to Amberwolf again for the idea :thumb:

I've ordered up a 2.0 x 2" and 2.15 x 20" schwalbe tire and plan to stuff the flexy little tioga tire inside. Both of these tires are rated for "50kmh", aka 31mph, so i'm thinking i might have a workable tire solution between one of the two.

If the 2.0 x 20 works, then i think i can run the tire in a tire setup on the 30mm leaf and get this build on the road.


I went through a CT scan to see if i have enough bone, so fingers crossed on that. If i have enough bone, i'm throwing the motor on and enjoying the damn thing :bolt: :bolt: :bolt: :bolt: :bolt: :bolt: :lowbatt:, otherwise the pedal bike riding continues until bone density improves. :cry:


It was a really windy day, so i also went to the outskirts of downtown to see if i could find any displaced coroplast signs to build a rear tail fairing with, and i managed to find 4! It wasn't hard at all, these things had became litter. I tucked them away between me and the seat ( how convenient! ) and rode off with my prize.

The ones i picked weren't prime specimens; a few looked like they'd been stepped on. So they'll just be used as a mockup tail fairing, until i can find some primo ones that look abandoned. ( political season is not done here yet, so the coroplast harvesting isn't too great )
 
Frock. I saw the results of my CT scan and they're abysmal. I'm healing slower than expected. The fixator is not coming off this month. :cry:

Anyway, do i want to pedal around without a motor for another ~3 months? hell no. Once i finish the tire in a tire experiment with the schwalbes, it's on. I will continue walking and add heavy squats to my physical regimen.
 
I'm sorry your not building bone at the expected rate. Did they say anything about impact vs resistance activity? This would be the difference between an elliptical (or cycle) and a treadmill training. The first is more beneficial to the joints, the other to the bones. I'm mostly just curious.

That's interesting that the double tire idea works so well! I'll have to look into it too at some point.

I'm actually taking a look at the possibility of a sectional 3D printed tube. It'd be like a solid tube, but printable, somewhat hollow (lighter), and able to be assembled.
 
I've poured through medical literature for months. I cannot really tell what kind of activity is best; a lot of the papers contradict each other.
I would guess that walking would be the best activity. After all, it's what you're designed to do. I've found that nature usually knows best. But squats and bicycling can't hurt!
 
xray_july.jpg

Just got back from the doctor. Doc says i'm making faster progress at healing than before. The photos show a difference of one month - the latest is on the right. It doesn't look like a big difference, but it is.

I also have a visible inner quad muscle on the right leg for the first time in my life. I'm up to squatting with 60lbs of extra weight. Freaking amazing. I used to squat 120lbs, but i still didn't have inner quads :shock:... goes to show how twisted bones can lead to insane muscle imbalances.. no wonder my knee caps point outwards!!

I think the nightly bike ride and walk is paying dividends. Doc loosened the fixator frame so that the load on the bone is greater. I imagine this means that the biking and walking will be more effective at prompting bone growth. There's a possibility i can have this frame off next month, so i want to tilt the odds in my favor even more, thus... no motor, for now :lowbatt:

But there's plenty to do. I need to figure out how to mount the battery. There's also some unsolved mysteries with how the rear and front tail fairing will mount. And the tires for the Tire In A Tire 2.0 experiment, so the build will continue :)
 
It was 90 degrees out but cloudy and i knew i had a fairly well shaded route to the bicycle collective, so i filled up the tires and went on my way.

This time, instead of 65 psi, i pumped them to 75 psi. Holy moly, the tire in a tire reallllllly likes that. I am now able to pedal another gear higher than before. I think the weight balance of this kind of bike creates a lot of rear tire deformation when i sit on it, and this creates all this extra friction, moreso than a regular bike. Maybe the tire in the tire also adds other dynamics..

The bike is not as fast as when it had the slick tioga on it ( at a meager 50psi ), but we'll see how the schwalbes roll tomorrow... fingers crossed.

For the rear fairing, i was fixated on the idea of using a bicycle rim of just the right size as part of a frame for the coroplast panels to attach to. At the bicycle collective, i measured the various wheel sizes to see what would fit my "air footprint", and i decided that the right size would be either 18" and 20". I came back with a few various sized rims to cut in half.

IMG_20190709_165813329.jpg

IMG_20190709_175705276.jpg
 
I was out testing the 2.0 schwalbe big apple with the tioga inside. The tioga takes up to 90psi. The schwalbe takes up to 70psi. I inflated to 70 psi.

Everything was great for about 7 miles. The Schwalbe with the tioga inside rode a smidge faster than the crappy CST. Until it didn't.

what-kind-of-flat.jpg

I found out that the tioga is in the beginning stages of dry rot. The tube was also particularly thin. We can see that the tioga's inner pattern wore into the tube. I wonder if the issue is multiple factors, or just one. I've never seen this kind of failure before.
 
Doc adjusted my leg and it feels like i went back an entire month, in terms of pain and functionality, so i'm out of the game for a bit :lowbatt:. When i'm able to do something beyond hobbling around on crutches, my eye is on completing that fairing.

At least i can drive!! but pedaling? ouch! :shock:
 
Of course i couldn't help but to ride anyway. Wanting to pull the cannondale apart to start building the fairing, i still needed something analog to pedal around. I took the motor off my roadbike and went on my way, and had a harsh reminder of everything i hate about upright bikes.

The Cannondale is a relaxing experience to ride; the seat coddles you.. there's no pain.. always a smile. I'm never in a rush, although hitting >20mph on flats is exhilarating and i have a tendency to race myself and others when possible. If i had nothing to do, i'd ride it all day. Because of the dual suspension, i drop off curbs or hit irregularities without any consideration. The only drama is when you have to steer around obstacles at <10mph, but that's rare.

The roadbike is a constant source of tenseness and pain. I'm in a rush to get off it as soon as i get on, therefore i'm always giving it maximum exertion. Because of the drop bars, you need to crane your neck in an unnatural position at all times, and eventually that hurts. I also develop some pain in the lower back at around the 30 minute mark. Because of the lack of suspension, if you're dealing with uneven pavement or sidewalk entries, you always need to look out for when you need to shift your body weight; if you don't, you risk a pinch flat or a harsh shock to the base of the spine/sit bones/wrists. Instead of enjoying the scenery, your head is down, focused on avoiding irregularities in the road to prevent shocks, and also anything that could disturb the half inc h of rubber between you and the road.

IMHO both of these bikes are roughly as fast as each other. The recumbent is faster on the flats, but slow on climbs. I complete my daily route about 5% faster on the road bike, likely because i am pushing harder so that i can get off the bike sooner, and the fact that my route is basically a rollercoaster, with lots of time spent climbing 1-3% grades.

The cannondale has some pretty wide tires for a pedalbike, and the suspension eats some power, too. So it's not as fast as it could be. I imagine that a skinny wheel laid back recumbent is like piloting a bullet train compared to both of these bikes. I kinda want one now.

I've decided to rid myself of the roadbike and replace it with a speed oriented recumbent to complement this big, fast, heavy, tank of an ebike i'm building. I guess i'm a recumbent guy now. :shock:
 
neptronix said:
<snip>

I've decided to rid myself of the roadbike and replace it with a speed oriented recumbent to complement this big, fast, heavy, tank of an ebike i'm building. I guess i'm a recumbent guy now. :shock:
Click to expand...

I've come to a similar conclusion, but it is more about the drop bars than about road or upright bikes per se. I think I'll replace my road bike drop bars with a flat bar perhaps with bar ends before I give up on it. I really like "walking" on the pedals and can find comfort in balancing my weight between the seat, pedals and handlebars. But I think I'm done with drop bars and trying to ride with a flat back.
 
wturber said:
I've come to a similar conclusion, but it is more about the drop bars than about road or upright bikes per se. I think I'll replace my road bike drop bars with a flat bar perhaps with bar ends before I give up on it. I really like "walking" on the pedals and can find comfort in balancing my weight between the seat, pedals and handlebars. But I think I'm done with drop bars and trying to ride with a flat back.
Click to expand...

I usually have my hands on the top of the drop bars to keep the lower back pain at bay. Even still, the positioning of the spine isn't right. A cat or dog would be very comfortable in an unsupported, flat horizontal spine position... but we don't have the posture muscles of a quadriped.... yeah.

Yeah, it's just not worth it for those extra few mph, to drop down low. Visibility also goes to shit when you lean forwards. It's kind of a hack. The hacks that make more speed on an upright bring more compromises than ones you'd make on a laidback bike to get more speed.

To me, an upright bike is lower back pain free when you've got a hybrid handlebar position, somewhere halfway between a dutch cruiser and a mountain bike. But the tense feeling is still there. The excellent view from a MTB or hybrid handlebar position is something a recumbent will never have. It is the only real thing i find missing when laid back.
 
I tried out the tire in a tire with the CST hookworm knockoff ( real squishy rubber ) inside the schwalbe big apple.
It had the rolling resistance of a motorcycle tire. It was really, really bad. My maximum pedaling speed was a pathetic 18mph.
The tire also some bounce and wobble in it, which felt a lot like riding a flat tire. Even at 70psi.
The only thing it had going for it was low inertia.

The outer tire is fast as hell without a second layer. So it appears that rolling resistance is generally a property of how rubber deforms around things. Therefore, the ideal inner layer is a very stiff one.
 
A side benefit of very stiff rubber for an inner liner is that it would also be harder to penetrate than the softer squishier stuff.

If you needed grip for traction / braking, you could use a squishier outer tire and a harder inner "boot" tire.
 
Yeah, sounds about right.

Anyhow, i rode the Schwalbe Big Ben Plus ( 20 x 2.125" ) without an inner tire for contrast and was able to ride up to the top gear pretty consistently. I hit a peak speed of 23.4 mph on flat ground. It was a real thrill ride, and i took the bike offroading and caught a bit of air a few times :lol: :thumb:

I've decided that the tire in a tire is feasible but not optimal. So the eZee motor will ride on the lighter weight Hutchinson moped tire, which has bit more friction than the best Tire in a Tire setup, but i'm okay with that... :)

The big DD has to wait until i get a battery to put in parallel as it will need more power because spoking down to an 18" and using a tire in a tire setup is a bit too iffy for something that will still hit a peak speed of 46mph. I think that's cutting it a bit too close.

I think my doc will loosen the leg frame again tomorrow. Hopefully my bone building activities have paid off.
 
Doc says that 2 pins in my leg have such a high level of infection that they need to be taken out, and replaced. This isn't super atypical though..
He also says a realistic expectation for removing the frame is in 2 months. I'm kind of gutted over it.
This means that i'm getting put in a cast in September, then healing that, which is going to take some months in itself.

It will be winter by the time i get a motor on this. Then it'll be way too cold to ride..

Well, sorry for the anti climax. I'm having fun riding an acoustic bike in the meantime. I'd rather be commuting to my work space ( 12 miles away ) on an electric, but i know damn well i get a bit lazy when the motor's on, especially during those uphill sections, where i SHOULD be stressing the bone as much as possible so that i can get this damn thing off sooner than later..
 
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