High performance & durability Cannondale Semi Recumbent

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High performance & durability Cannondale Semi Recumbent

Post by neptronix » Jan 24 2019 5:13pm

Just a preview for now.

Goals for this build:
45mph continuous top speed capable on less than 2kw using aero aids.
Short kammback tailbox fairing with storage for batteries and a complete set of tools and spares to service the bike in the field.
Medium sized front fairing - must be custom.
The ability to climb a 7% grade perpetually for 12 miles.
1kw of regen for descending above hill. No mechanical rear brake.
~2kwhr battery for at least a 40 mile range at 45mph, or 200 at 25mph.
Tires must be thick enough to resist goathead and tack punctures.
Optional pack to boost the voltage to ~100v for testing of various aerodynamic aids at ~80mph on a closed course. May go for some land speed records.
Optional detachable safety cage for the above.

Here is a video of the bike as it stands today, and why i chose it.



So far, my future components list is..
2x 50.4v 21ah Samsung 30Q packs from em3ev or maybe custom built 42ah 50v pack.
Leafmotor 1.5kw in custom 3T winding.
18FET controller for maximum durability during long ascents.

Estimated completion date is fall of this year, maybe earlier.. depending on how the surgery goes.
Efficiency is everything :bolt:

My first major build: 1.6kW 8T MAC motor on a Trek 4500.
The new all-arounder: Leafmotor 1500w @ 4kW on a Turner O2 full suspension.
The monster scooter: 20" eZee on a Cannondale Semi Recumbent.
Whipper-snapper: ? on a lightweight BikeE Semi Recumbent

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Re: High performance Cannondale Easy Rider Recumbent

Post by neptronix » Jan 24 2019 5:14pm

reserved
Efficiency is everything :bolt:

My first major build: 1.6kW 8T MAC motor on a Trek 4500.
The new all-arounder: Leafmotor 1500w @ 4kW on a Turner O2 full suspension.
The monster scooter: 20" eZee on a Cannondale Semi Recumbent.
Whipper-snapper: ? on a lightweight BikeE Semi Recumbent

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Re: High performance Cannondale Easy Rider Recumbent

Post by neptronix » Jan 24 2019 5:14pm

reserved
Efficiency is everything :bolt:

My first major build: 1.6kW 8T MAC motor on a Trek 4500.
The new all-arounder: Leafmotor 1500w @ 4kW on a Turner O2 full suspension.
The monster scooter: 20" eZee on a Cannondale Semi Recumbent.
Whipper-snapper: ? on a lightweight BikeE Semi Recumbent

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Re: High performance & durability Cannondale Semi Recumbent

Post by neptronix » Jan 27 2019 5:56pm

IMG_20190127_142831.jpg
Took v0.2 of the bike out for an icy snowy ride to see how it handled it with the fairly slick motorcycle tire. I have to say i'm super impressed.

Normally when you hit uneven ice on an upright bike, it'll upset the front wheel pretty bad and threaten to send you flying off. On a semi recumbent, it's the rear wheel that shifts position, not the front. You can hit ice at a pretty good speed and it will just shift the rear of the bike a few degrees, which you can correct for pretty easily. If things get too hairy, hit the brakes and throw a leg out. Easy to avoid a crash even when you get stupid :mrgreen:

The one thing that doesn't stand up is this Samsung 30Q 14AH pack. Damn thing sags like crazy on 30A in freezing temps. Barely usable. Can't wait to upgrade it!
Efficiency is everything :bolt:

My first major build: 1.6kW 8T MAC motor on a Trek 4500.
The new all-arounder: Leafmotor 1500w @ 4kW on a Turner O2 full suspension.
The monster scooter: 20" eZee on a Cannondale Semi Recumbent.
Whipper-snapper: ? on a lightweight BikeE Semi Recumbent

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Re: High performance & durability Cannondale Semi Recumbent

Post by Chalo » Jan 27 2019 11:55pm

I gotta say-- you've used recumbent layout, small wheels, and power assist astutely to apply their strengths to each other's weaknesses. I'm looking forward to see how this bike does for you in the long term.
This is to express my gratitude to Justin of Grin Technologies for his extraordinary measures to save this forum for the benefit of all.

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Re: High performance & durability Cannondale Semi Recumbent

Post by APL » Jan 28 2019 3:41pm

I've been following your threads, but haven't had anything to contribute. I had to look up goatheads, because we don't
have them here, thank god. Miserable little farts! Have you thought about a flame thrower? This is war!! :lol:

How many states are molested by these things? (so I can stay away) I would think that the tire companies would step
up and address the issue,..theres bucks to be made here.

Anyway, I had my doubts about semi recumbents, because all the weight is above the axles, but it sounds like it handles
well in spite of that. Being able to put a foot down goes a long way.

Good luck Nep, and I enjoy the thread!

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Re: High performance & durability Cannondale Semi Recumbent

Post by neptronix » Jan 28 2019 4:08pm

Thanks for your comments and compliments.

Goatheads are present mostly in the southwest corner of the United States. They are usually at their worst in fall. Some people have actually used fire or biowarfare with insects to try to eliminate them. Without many bicyclists here, i don't think there's been any attempts to deal with the problem.

I've talked to dozens of tire manufacturers to see if i can get the bike tire problem solved. There is simply no interest. But the Stromer company has had pirelli make them some motorcycle-esque looking 27.5" tires. I contacted a rep of pirelli and stromer to see if i could just get my hand on a pair. No go!

One interesting thing is that if you are above say, 10mph.. you can corner significantly faster than most upright bikes. You can counterbalance with your legs AND your torso. Changing the tires out to ones with a circular shape has helped even more. Once my surgery is over and i've learned how to walk again, i would like to prove this in racing. The ultra low center of gravity is a huge cornering advantage.

At low speeds, it's much more of a pain than an upright bike. The sidewalk is a bad place to be because you can't quickly maneuver due to the long wheelbase. You'll be sticking a leg out often.

This bike will take a 3.4" tire in the back and maybe a 3.0" in the front. I'm tempted to go full fatbike.. but the bike is already 40lbs stock and i'm up to ~70lbs already!
Efficiency is everything :bolt:

My first major build: 1.6kW 8T MAC motor on a Trek 4500.
The new all-arounder: Leafmotor 1500w @ 4kW on a Turner O2 full suspension.
The monster scooter: 20" eZee on a Cannondale Semi Recumbent.
Whipper-snapper: ? on a lightweight BikeE Semi Recumbent

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Re: High performance & durability Cannondale Semi Recumbent

Post by Chalo » Jan 28 2019 6:25pm

APL wrote:
Jan 28 2019 3:41pm
How many states are molested by these things? [goatheads] (so I can stay away)
Image
This is to express my gratitude to Justin of Grin Technologies for his extraordinary measures to save this forum for the benefit of all.

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Re: High performance & durability Cannondale Semi Recumbent

Post by amberwolf » Jan 29 2019 3:42am

APL wrote:
Jan 28 2019 3:41pm
I had to look up goatheads, because we don't
have them here, thank god. Miserable little farts! Have you thought about a flame thrower? This is war!! :lol:

How many states are molested by these things? (so I can stay away) I would think that the tire companies would step
up and address the issue,..theres bucks to be made here.
Since the tire companies also make tubes (at least some do), they can make plenty of money that way. ;)

I used to have a problem with goatheads here in the yard so bad that one of the dogs with more tender feet (Hachi) would limp around with one in her paw, then hit another and another, and then just sit there holding up as many feet as she could, until I came to rescue her. If I was at work, that could be all day long. :( So I started a "war" on them, that is still going. A couple places in the yard I actually just had to take a couple inches of topsoil off for several square yards, and bin it in an unvented container for a long time (couple years?) in the heat with dampness to kill everything in it. Nowadays, I only get a few dozen sprouts start up in that area of the yard when it gets warm and dampish, and a handful in scattered areas around the edges of teh yard where things can be tracked in (at the gate) or blown in thru the fence (at the alley). I catch them mostly before they're a couple inches across; somtimes one escapes till it's several inches and is beginning to grow teh goatheads.

The front yard seems to be mostly immune to them, which is wierd--I've only ever seen a few of them, randomly scattered, now and then.


Someday, I hope to have a yard free of them...but I'm not making any bets on it.

And I wouldn't wanna ride on any dirt trails around here--it's bad enough just on pavement *near* them, like on the paved canal paths.

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Re: High performance & durability Cannondale Semi Recumbent

Post by APL » Jan 29 2019 1:37pm

I suppose it's a dumb idea, but could a person cut up another tire, say like a Thickslick, and insert it 'inside' the outer
tire? It would have to be cut at one point and sized, but not that much different from a poly liner.

I know I've seen some extremely thick and heavy tubes, filled with goop, for sale, but they weigh more than the tire itself!!
Still, if it works...?

Also, in the old days we had bent wire 'tack removers' for lack of a better term, that mounted under the brakes, and
rubbed the tire surface, to supposedly knock off anything before it imbedded itself. Not sure if they actually worked not.

Otherwise, a leaf blower would fit under there,.. (just kidding :lol: )

Sounds like you already have it dicked with the tires your using, :thumb: .. I'm just thinking out loud.

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Re: High performance & durability Cannondale Semi Recumbent

Post by APL » Jan 29 2019 1:55pm

Actually, I was thinking of a really small blower that would channel some air through small tubes down to where
the tire touches the road, just enough to keep that area clean. But I suppose thats just as dumb as all the other
ideas I had.

Sorry, ..I'l shut up now,... :confused:

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Re: High performance & durability Cannondale Semi Recumbent

Post by Warren » Jan 29 2019 2:02pm

Chalo wrote:
Jan 27 2019 11:55pm
I gotta say-- you've used recumbent layout, small wheels, and power assist astutely to apply their strengths to each other's weaknesses. I'm looking forward to see how this bike does for you in the long term.

Now I know where this cold snap came from. It is hell freezing over. :-)

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Re: High performance & durability Cannondale Semi Recumbent

Post by Chalo » Jan 29 2019 2:22pm

Warren wrote:
Jan 29 2019 2:02pm
Chalo wrote:
Jan 27 2019 11:55pm
I gotta say-- you've used recumbent layout, small wheels, and power assist astutely to apply their strengths to each other's weaknesses. I'm looking forward to see how this bike does for you in the long term.

Now I know where this cold snap came from. It is hell freezing over. :-)
It's not my cup of tea, but it's smart. Heavy tires and their gyro stability help rectify goofy recumbent steering. Suspension addresses the harshness of small wheels. Abundant motor power makes a slow bike fast. Etc. This bike has a passel of potential problems and irritations bundled together with what seem like effective remedies for them. If it's also fun to ride and easy to live with, then it's a success. I hope it is.

It wouldn't be the right pick for a fourth floor walkup, or a city bike courier, but for a person with a garage in a suburban setting, I don't see any deal breakers.
This is to express my gratitude to Justin of Grin Technologies for his extraordinary measures to save this forum for the benefit of all.

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Re: High performance & durability Cannondale Semi Recumbent

Post by Warren » Jan 29 2019 3:21pm

Chalo wrote:
Jan 29 2019 2:22pm
This bike has a passel of potential problems and irritations bundled together with what seem like effective remedies for them.

The natural order is restored. :-)

https://image.politicalcartoons.com/214 ... 214784.png

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Re: High performance & durability Cannondale Semi Recumbent

Post by neptronix » Jan 29 2019 4:53pm

Chalo wrote:
Jan 29 2019 2:22pm
It's not my cup of tea, but it's smart. Heavy tires and their gyro stability help rectify goofy recumbent steering. Suspension addresses the harshness of small wheels. Abundant motor power makes a slow bike fast. Etc. This bike has a passel of potential problems and irritations bundled together with what seem like effective remedies for them. If it's also fun to ride and easy to live with, then it's a success. I hope it is.
Two things helped the stability and twitchy steering that's inherent in these bikes..
1) Switching to wide BMX handlebars. I can steer the bike with one hand now. The original handlebars were curved inwards and put your hands in a much narrower position. Twitch prone by design.
2) The bigass heavy tires helped too.

But the good news is that even with the original twitchy setup, the bike was extremely hard to disbalance. All thanks to the low center of gravity and ridiculously long wheelbase.

The bike is now more stable and less twitchy than my 700c roadbike - provided that you get it above 5mph. Easy to do with a short throttle blast.
Efficiency is everything :bolt:

My first major build: 1.6kW 8T MAC motor on a Trek 4500.
The new all-arounder: Leafmotor 1500w @ 4kW on a Turner O2 full suspension.
The monster scooter: 20" eZee on a Cannondale Semi Recumbent.
Whipper-snapper: ? on a lightweight BikeE Semi Recumbent

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Re: High performance & durability Cannondale Semi Recumbent

Post by neptronix » Jan 29 2019 4:56pm

Oh yes i have tried every tire hack except for the tire in tire. A few people told me they had serious issues with that. The slime stuff left me stranded with no ability to patch a wet tire more than once. Same with stans.

Imagine if cars or motorcycles were built this way.. super thin rubber for efficiency, but you gotta pull over after a few hits from goatheads or metal. Ridiculous. Fat thick rubber is the only way out, and coincidentally that's exactly how tires for everything else are made.

In 75,000 miles of driving, i've had a flat once. On 50 miles of riding, i will absolutely have a flat tire on any bicycle oriented solution. Unacceptable.
Efficiency is everything :bolt:

My first major build: 1.6kW 8T MAC motor on a Trek 4500.
The new all-arounder: Leafmotor 1500w @ 4kW on a Turner O2 full suspension.
The monster scooter: 20" eZee on a Cannondale Semi Recumbent.
Whipper-snapper: ? on a lightweight BikeE Semi Recumbent

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Re: High performance & durability Cannondale Semi Recumbent

Post by amberwolf » Jan 29 2019 11:29pm

APL wrote:
Jan 29 2019 1:37pm
I suppose it's a dumb idea, but could a person cut up another tire, say like a Thickslick, and insert it 'inside' the outer
tire? It would have to be cut at one point and sized, but not that much different from a poly liner.
Something like that is common; there's a bunch of threads about tires, tubes, punctures, flats, walks-of-shame, etc., and variations on this are discussed in a few of them if you need details of other versions than mine. :)

Myself, I now use 16" moped tires and tubes on the rear 20" bike wheels of the trike, and they solved the puncture problem and actually cost less than bike tires that would've done the same kind of thing with technology rather than rubber thickness.

The front is a 26" wheel though, and I haven't tried to find a (19") MC/moped tire to fit it. Instead, I use the same solution I've done for a while now, which is to use a layered approach.

Regular tire liners, like the Slime things, have a tendency to wiggle and slip, not fully protecting the center tread area very well, unless you use really high pressures in a tire. If you want a comfy ride, you have to decrease the pressure, which lets them wiggle. You can't glue the liner to the tire, or else it won't deflect objects that puncture the tire, and they'll just puncture the strip, too. (their points won't be able to slide across it's surface, and instead will just go thru it).


So I've used two different methods to help with this. What I do now is take old tubes that have become unpatchable for whatever reason, and cut the valve stem off. Then I slit them along the inner circumference, and enclose the actual tube I'm going to use inside this. If they're not thick (3mm+) then I'll use two. If I have one handy when I setup a wheel, the slime liner then goes between this contraption and the inside of the tire.

I've also used an old semislick tire with the bead cut off, to do the same thing. I don't cut the tire to make it shorter to fit inside, I just pick a tire that's enough smaller than the one I'm using. That's difficult to find pairs like that in my used stuff, so that's why I now use the tubes instead. Same effect--makes it more likely to be thicker than the most common things that will stick in it (which is also the point of the moped/MC tires).

Both methods work very well, but they do make heavy wheels.

The slime liners work better at deflecting nails and stuff when used with the slit-tubes than with tires, probably because they can more easily deform to let the nail slip past and force it toward the sidewall, rather than being unable to deform and letting the nail poke thru the liner instead. But the tires themselves are harder and so are more puncture resistant to smaller more bendy types of debris.... Pick your poison. ;)

The only time I have had trouble with tire-in-tire stuff is if I didn't cut the bead off, the wire in the bead eventually poked thru the tube and cause a flat instead of preventing one!

But others have sometimes had other issues with the setup; don't recall which ones.

I don't know anyone that had trouble with the multiple tube setup.
I know I've seen some extremely thick and heavy tubes, filled with goop, for sale, but they weigh more than the tire itself!!
Still, if it works...?
I've used Slime in tubes before, and it can work, but if you get a gash or something it doesn't usually hold even if it can plug it, and it makes it next to impossible to patch the hole on the roadside.

Regarding weight, unless you're using higher technology (kevlar linings, etc), which still isn't that common in bike tires (there are some, but not a lot, and not a big selection of treads, sizes, compounds, etc., in what *is* out there), then simply using thicker tires will do more than most other things to keep punctures minimized. Thicker tires are heavier, so if you need "extreme" puncture resistance, you end up with heavy tires, if you go down that path.

Basically it means you choose where the weight goes to, but you still end up with a heavier wheel, without some sort of high-tech lining.

Also, in the old days we had bent wire 'tack removers' for lack of a better term, that mounted under the brakes, and
rubbed the tire surface, to supposedly knock off anything before it imbedded itself. Not sure if they actually worked not.
They can work, but depends on what stuff, and what damage it already did to the tire.

Others have put what amount to brooms out front of the tire, too. Or magnets, etc. Depends on the kind of debris.

Otherwise, a leaf blower would fit under there,.. (just kidding :lol: )
That's been done, too (not by me)
https://www.google.com/search?q=leaf+bl ... 8&oe=utf-8

From what I've seen, works best if you're riding pretty slowly, as the force needed to move the stuff out of the path is high enough to need to be fairly close to the outlet of the blower. One can use a narrower nozzle to concentrate the airflow, but then the path cleared may be too narrow. Placing the outlet directly in front of the tire, blowing at an angle toward the side, would probably be most effective.

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Re: High performance & durability Cannondale Semi Recumbent

Post by APL » Jan 30 2019 1:32pm

Just thinking outside the box again, (hell, I've never even seen the box! :lol: ),..but I was thinking of a
passive system that uses two small 'sail-like' wind collectors, or scoops, that capture the air and concentrate it down
some 'short' tubes to the front tire footprint. They could clamp to the axle ends.

It would take a good design to make it look cool enough, and probably only work at higher speeds, but thats where most
of the riding is done.

Not a solution to the problem at present, but maybe worth thinking about. Nonexistent inventions don't help things much.
(The things that go through my head at night! :confused: )

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Re: High performance & durability Cannondale Semi Recumbent

Post by amberwolf » Jan 30 2019 2:14pm

APL wrote:
Jan 30 2019 1:32pm
Just thinking outside the box again, (hell, I've never even seen the box! :lol: ),..but I was thinking of a
passive system that uses two small 'sail-like' wind collectors, or scoops, that capture the air and concentrate it down
some 'short' tubes to the front tire footprint. They could clamp to the axle ends.
You'd have to be going pretty fast to get enough flow to blow anything significant out of the path, but then you'd be going to fast for that flow to be enough of a "lead time" to help.

If the sails were large enough to concentrate enough air to move things effectively out of the way, they'd present significant drag.

Keep in mind how much air a leaf blower moves, and what it takes for one of *those* to be effective. ;)


I get lots of ideas that seem good at first, but end up impractical or flat out impossible. :oops: I usually find the box by smashing my face against one of the walls. ;)

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Re: High performance & durability Cannondale Semi Recumbent

Post by Warren » Feb 01 2019 12:23pm

neptronix wrote:
Jan 29 2019 4:53pm

The bike is now more stable and less twitchy than my 700c roadbike - provided that you get it above 5mph. Easy to do with a short throttle blast.
Yup. My two electric assist recumbents are more stable than any upright I have ever owned. I have ridden for many miles with hands pumping my knees, only touching the bars to shift or brake.

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Re: High performance & durability Cannondale Semi Recumbent

Post by neptronix » Feb 01 2019 12:41pm

Warren wrote:
Feb 01 2019 12:23pm
Yup. My two electric assist recumbents are more stable than any upright I have ever owned. I have ridden for many miles with hands pumping my knees, only touching the bars to shift or brake.
Since you have two electric recumbents, i gotta ask you something.

Yesterday i was riding along and some idiot in a car tried to merge into my lane. It was a compact car, so me and the driver were both at eye level. He just didn't look before he tried to merge.

I was thinking about how this style of bike takes a fall. I imagine that if i held the front wheel straight, tucked my knees in, and pushed my legs against the pedals to stay seated, i could avoid my body touching the ground, because the handlebars and seat, which are both many inches wider than my body, would take the impact.

In addition to that, the low center of gravity and long wheelbase makes the balance of the bicycle hard to upset when it's in motion.
And also, you have a much shorter distance to fall. If your body hits the ground, the likely injury is road rash, not impact.

I've thought that a good way to make this bike safer would be to install some wide bars on the front, because you cannot depend on yourself to hold the wheel straight during a crash. This bar could also be used to mount a fairing.

Overall i feel safer on this style of bike, because i know what happens when you crash an upright bike and have the scars to remind me. This seems so much better.

What's your 2 cents?
Efficiency is everything :bolt:

My first major build: 1.6kW 8T MAC motor on a Trek 4500.
The new all-arounder: Leafmotor 1500w @ 4kW on a Turner O2 full suspension.
The monster scooter: 20" eZee on a Cannondale Semi Recumbent.
Whipper-snapper: ? on a lightweight BikeE Semi Recumbent

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Re: High performance & durability Cannondale Semi Recumbent

Post by amberwolf » Feb 01 2019 10:12pm

Crazybike2, semirecumbent LWB, mostly protects the rider in a sliding crash, because the seat frame protects the body, and legs, as long as you pull your leg in toward the frame.

The wide bars I have (kinda like cruiser bars, but used upright), with teh angled grips, don't grab the ground like straight bars in most skids, and hands can be moved inwards to protect them.

The cranks can protect your feet, if you ahve time to pull them out of the way--I didn't when I crashed on the kart track turn during deathrace, and I broke my ankle. The first crash I had on the same track I only scraped up the knee of my protective gear, in the gravel to the side of teh track.

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Re: High performance & durability Cannondale Semi Recumbent

Post by www.recumbents.com » Feb 04 2019 12:57pm

Ha. I have crashed recumbent bikes a lot, because racing. Usually you end up landing on your butt and sliding. This means you get road rash on your butt, upper thigh and usually your elbow / forearm. Not bad compared to the crash modes on upright bikes.

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Re: High performance & durability Cannondale Semi Recumbent

Post by APL » Feb 04 2019 2:17pm

Just wanted to add that it's not likely that a person would keep the hands on the bars in a crash.

The body has an automatic response to extend the arms first, and protect the head. This is one of the main reasons
cyclist wear gloves, road rash on the hands will last a month, and keep you from doing anything.

Since a recumbent is lower, I would imagine that one arm would extend, and the elbow..and forearm would take the
brunt of the force, along with the thigh of course, just like the last post stated.

Much better than the road bike, where broken wrist's are first, collar bones second, and head injuries, are the common
order of things.

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Re: High performance & durability Cannondale Semi Recumbent

Post by neptronix » Feb 04 2019 7:58pm

Sounds like i'm on the right track with the crash bar idea then. Thanks for your feedback, fellow e-recumbent riders.

The question is how to create a crash bar that will not lead to injury itself. I think the best place for this bar is in the center of the frame so that if the legs flop around during a crash, they are unlikely to touch it.

If i let go of the handlebars during a crash, i'm in trouble because i drop to the ground and all these safety features don't work.

I think i need to practice crashing the bike, with a slow motion camera active while i do it. I think it would be really cool to come up with an inobtrusive safety 'cage'. Perhaps i could design some kind of handlebar rotation range limiter that would ensure that the handlebars + crash bar + seat act as a triangulated safety buffer, and their friction on gravel would also help reduce the amount of road rash.

Bike safety is something we don't talk about enough on this forum, considering there's plenty of people like me that like to go fast.
Efficiency is everything :bolt:

My first major build: 1.6kW 8T MAC motor on a Trek 4500.
The new all-arounder: Leafmotor 1500w @ 4kW on a Turner O2 full suspension.
The monster scooter: 20" eZee on a Cannondale Semi Recumbent.
Whipper-snapper: ? on a lightweight BikeE Semi Recumbent

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