High performance & durability Cannondale Semi Recumbent

As you noted the biggest thing you want to avoid in a crash is contact with the frame. Don't put crash bars between your body and the pavement. It's better to use something like flat like Coroplast on the sides which will protect you from roadrash. I have rarely crashed while street riding. Most crashes were because of an emergency stop where I didn't get unclipped fast enough and just fell over. Yeah, embarrassing. I also crashed once at speed because a tire blew off the rim. Lots o' road rash because I was just wearing lycra. I don't think you need to add anything to that bike for crash protection, probably protective clothing is better.

I'm not sure it's possible with that bike, but a 20" wheel on the front would make it more stable, especially around corners. It would also give you more trail which would make it more stable at high speeds but harder to handle at low speeds.

I really like the motorcycle tire. What width of 20" bike rim is appropriate for those?

Warren
 
www.recumbents.com said:
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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What he said. I have only had two real bicycle crashes. I crashed hard on my Linear, going about 18 mph on a gravel road. Lots of road rash. On my TCR, on pavement, I broke my clavicle and scapula. That road was a looong way down.
 
Yeah-- if you can't maneuver worth a damn, can't hop over a hole or obstacle (nor even lift the front wheel over the lip), and can't stick out your leg to brace without risk of breaking it-- you'd better be able to crash well.
 
markz said:
Why on earth would you block someone like Chalo?
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I guess he rides a 'bent because he's easily butthurt. :wink:
 
Warren said:
What he said. I have only had two real bicycle crashes. I crashed hard on my Linear, going about 18 mph on a gravel road. Lots of road rash. On my TCR, on pavement, I broke my clavicle and scapula. That road was a looong way down.
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Me too. Three crashes on an upright bike. All involved extensive road rash; one took three days until I could ride at all. One crash on my Longbike, and nothing other than some bike damage.
 
Warren said:
What he said. I have only had two real bicycle crashes. I crashed hard on my Linear, going about 18 mph on a gravel road. Lots of road rash. On my TCR, on pavement, I broke my clavicle and scapula. That road was a looong way down.
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Linear? Oh I see its a recumbent aka 'bent
TCR? Giants road bike?
 
Chalo said:
markz said:
Why on earth would you block someone like Chalo?
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I guess he rides a 'bent because he's easily butthurt. :wink:
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We've had our first riding weather in a month, this week. Rode my recumbent 50 miles Monday for ice cream. Rode it 100 miles yesterday for lunch. Both done in blue jeans. My butt didn't hurt a bit. :) Saw lots of roadies in lycra, most of whom carried their bikes somewhere on a car.
 
neptronix said:
... Tires must be thick enough to resist goathead and tack punctures. ...
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Given the various ideas in the thread to address this, I believe it would be far simpler - and has a proven track record - to do what the mountain bike riders do - go tubeless with sealant:
  • Most go tubeless to lose the tube for a more supple flat/contact patch, so they have better grip (climbing, rocks, wet) or less dig-in for better float (sand, snow).
  • Those in an area that is heavy with goathead thorns or other hazards love it for being able to ride with significantly less chance of having a flat.
  • Lower rolling resistance: lose the tube and it's no longer dis-forming into the contact patch and back.
  • Others like the weight loss; although you lose the tube, you gain the sealant weight.
  • No more snake-bite flats, except those caused by actual snakes (which may seal up).

More detail
  • Goathead thorns and the like are a breeze, as are tacks, nails and screws. Many sticks too. Often even into sidewalls.
  • Riders go from one or more holes/patches/tubes per ride (one poor guy had near a hundred...), to maybe one a year they have to do something about.
    o Typical to not even notice there's been a puncture, until you're home and pull a few thorns out. If you do pull something out, it will likely seal on it's own (as happens when you're riding), but it's good practice to spin the tire a few times to ensure sealant gets into the puncture from the inside.
    o Many still carry a tube (or two). Usually if their using tubeless is new to them, or just because, and particularly if they're going on trails in back-country.
    o Some carry hole plugs, designed for bikes, similar (or different) to what we see used for car tires, to ensure they don't have a long walk home from out in the bush somewhere - self rescue, to ensure their friends can't laugh at them.
    o If you're fat biking in freezing weather or way out there, self-rescue may be the difference between living or not.
  • There are many sealants available off the shelf, along with various DIY brews, with formulas and track records online.
    o Watch out for someone who hasn't done their research jumping onto the first they find and try and promote it as the be all to end all.
    o All sealants are not equal. Research their effectiveness and longevity.
    o Many require regular maintenance of adding some ammonia to keep the liquid latex in the sealant from setting up; most sealants will eventually setup (called boogers) and require replacing.
  • Tubeless-ready rims (well, most of them) are great & easy. Usually pricey.
  • Instead of tubeless-ready rims ($), there are various DIY methods too, Getto Tubeless: wrapping the inside rim with tape or other plastic wraps, and split-tube tubeless.
    o Not all tapes and wraps are equal. Do your research. There is one famous tape that has widely varying results: appears to be due to age, storage or production runs - results will vary.
  • There are pros and cons with the various methods, and some people have less luck with a given method than others. Some tires will fit looser, or looser on various rims, so expect with some combinations you may need more tape/wrap/sealant than others do.
  • Again due to fit, sometimes a tire will pop into place or seal right up. Other times you need to wrap the circumference of the tire to encourage the bead to seat while you get air into it. This is usually with fat tires, but sometimes other mountain bike tires too. Smaller tires? Possibly.
  • Some tires aren't very air tight. Most of those will self-seal with the sealant, others will weep sealant, and would benefit from being pre-sealed on the inside by rubber cement.
    o Make sure you search for your tire, so you might find out in advance if you need pre-sealing.
  • There are various commercial products to help facilitate going tubeless, but results vary, can be pricey. Again, do your research.

Not doing your research or then not following proven materials & practices is pretty much ~= fail, along with a (sometimes long) walk. With much rants and posting afterwards. Plenty of people who don't read enough; plenty of their threads & posts.
But if you like to experiment, you can do that too.

places to start

sealant brews - interesting read, but long, brownie points / bragging rights if you read the whole thing (was over 125 pages before the forum condensed pages), but the best results are towards the end of the thread, along with new finds
https://forums.mtbr.com/29er-components/best-tubeless-brew-406115-43.html

tubeless tape
https://forums.mtbr.com/wheels-tires/tubeless-tape-thread-926021.html

search for split-tube tubeless and getto tubeless
 
Tubeless tires with sealant are a time-consuming hobby. We already have a hobby.

Did you ever stop to consider why no other vehicle with pneumatic tires routinely uses the stuff? It's a huge nuisance. There are limited applications where it makes sense, but fashion has compelled many people who have no such application for it to use tubeless with sealant, and to falsely claim advantages it doesn't have.

Example: "You can run lower tire pressure with tubeless." Um, no, you can't. The lowest tire pressure you can use is the minimum required to keep from bashing your rim against the ground. Tubeless does nothing to change this threshold pressure versus using a tube, but it takes away a layer of protection between rim and ground. You might (or might not) get "no more snake-bite flats", but you will dick up your rims instead-- unless you use adequate pressure that would work fine with a tube and no sealant. (Or with a tube that has sealant harmlessly contained inside.)

Tubeless-ready rims are not easy. They make changing a tire needlessly difficult even if you use a tube, because they're specifically designed to seal to the tire and not let it off. Alex Rims changing the excellent Adventurer to the tubeless-compatible Adventurer 2 moved that rim from the top of my go-to list to down near the forget-about-it bin.

Tire plugs won't help you when you burp your tubeless tire, and don't have an air compressor with you to get it seated again.

For weekend warrior MTB dudes who only have an afternoon at a time to go outside and play, and who benefit from having an excuse to hide in the basement from their wife and kids while they fool around with goopy tires, tubeless with sealant makes some sense. For transportational and streetgoing riders, it's more trouble than it's worth.
 
Thanks for your advice, but i've already chose the frame around the concept of using motorcycle tires for both puncture prevention and ride quality reasons. The bicycle already has a motorcycle tire where most of the weight rests and there's zero chance of me going back.

I spent 3 years dicking about with every other solution, and the sealants gave me the worse experience because the tire/tube cannot be patched when it is perpetually wet from sealant leaking. Sealant gave me the longest walk of shame possible, and that was no fun for someone with arthritis in multiple joints.

I've already had 12 walks of shame in the past 3 years over the course of maybe 1000 miles. Most of the year was spent driving a car out of discouragement. I have no interest in going back to flimsy bicycle tires, not when i am designing for a 200 mile range.
 
> Tubeless tires with sealant are a time-consuming hobby. We already have a hobby.
Yup
If you do it wrong. Or want to experiment.

> Did you ever stop to consider why no other vehicle with pneumatic tires routinely uses the stuff? It's a huge nuisance. There are limited applications where it makes sense,
Except where the application/need where it makes sense. Like thorns. And sealeant is used in many different types of vehicles where their application or location makes it an advantage, or a necesity.

> but fashion has compelled many people who have no such application for it to use tubeless with sealant, and to falsely claim advantages it doesn't have.
I've certainly seen that. Like your
> Example: "You can run lower tire pressure with tubeless." Um, no, you can't.
Happens when they don't research it enough or misunderstand.

> (Or with a tube that has sealant harmlessly contained inside.)
Practice by many shows that rarely works. Didn't work for two friends who tried them. Not once.

> Tubeless-ready rims are not easy. They make changing a tire needlessly difficult even if you use a tube, because they're specifically designed to seal to the tire and not let it off.
The ones I've seen have a shelf, and sometimes a containment ridge, so they're lightly sealed and easy to seat.

> Tire plugs won't help you when you burp your tubeless tire, and don't have an air compressor with you to get it seated again.
That's new to me. I've never heard of anyone expecting tire plugs to help them with that. I have seen where they use tire plugs for oversized punctures where sealant doesn't work. The techniques for seating tires without an air compressor are documented for those who don't have the use of a compressor, or realize they need to be able to deal with things on the trail.

> For transportational and streetgoing riders, it's more trouble than it's worth.
Except for applications, like goathead thorns, it makes sense.

If you're going to consider tubeless and/or sealant, you're goint to have to do some homework to learn how to do it so it works without fuss.

There's lots doing it reliably in harsh deserts, canyons and the 1000 mile ITI to Nome.
 
The bike shop that put stans sealant in my last set of bike tires said that they refuse to ride bikes in the park that's literally behind the store, calling it 'goathead gulch'.

Before that, a few employees said that everyone there uses stans sealant.

That's telling!

For me, stans sealant extended the average time to flat in the fall ( goathead season ) from around 15 miles to 45 miles, except i could not patch the tire in the field, so a flat was worse. It was slightly better than the time i tried slime.

I'd like to see makers of flimsy bicycle tire solutions benchmark their products in my hood. I spent some time at interbike trying to convince them to build something up to the task and none were interested.

There is a company here who makes a solid rubber tire as a solution for our area, but spoiler alert - the tire handles like crap at ebike speeds.
 
www.recumbents.com said:
As you noted the biggest thing you want to avoid in a crash is contact with the frame. Don't put crash bars between your body and the pavement. It's better to use something like flat like Coroplast on the sides which will protect you from roadrash. I have rarely crashed while street riding. Most crashes were because of an emergency stop where I didn't get unclipped fast enough and just fell over. Yeah, embarrassing. I also crashed once at speed because a tire blew off the rim. Lots o' road rash because I was just wearing lycra. I don't think you need to add anything to that bike for crash protection, probably protective clothing is better.
Click to expand...

You know, i am really hung up on the idea of an ebike having the same utility as a car. IE no outfit change needed. Lycra is something i'll never wear, for sure. I'd never use toe clips because of the instability at low speed you speak about.

I've thought about a side fairing but i want to make the bike to 'look normal' due to the high speeds i'll be traveling at and the potential legal risk that brings. The more normal the bike looks, the less attention it should get.

It seems like the idea of a crash bar is highly disputable in the motorcycle world and you might be right for being bearish on it.
https://www.quora.com/Do-crash-bars...tect-the-rider-If-so-which-types-are-the-best

www.recumbents.com said:
I really like the motorcycle tire. What width of 20" bike rim is appropriate for those?
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The manufacturers of these tires generally state 1.5 inches internally for the tires. I shoehorned the 2.25" into a 24mm ( almost 1 inch ) rim. For 2.25-2.75", i imagine a 32mm-40mm internal width rim would be the best choice.
 
I think your idea of a simulated crash is a good one,.. but how to do it? Maybe just start with a few simple fall over's
onto something soft? Sorry I'm at a loss for ideas here. :( Anybody else know how to do this? :?:
Anyway, the experiments might glean some good information straightaway, as every bike and rider's set up is a little different.
 
I have a big softmat i can fall on in the garage and film it at 120fps.
A bottom bracket will probably get destroyed in the process but that's okay.

My big leg surgery is in 3 months and will screw me up pretty bad and i won't be doing anything with bikes for a while though. During this time i plan to play with autocad and plan all the cool shit i wanna do to it. This thread will just be autocad porn for a bit.
 
Oh wow, i mistyped. My big leg surgery was in 3 days ( as of writing then ).

I've had the operation and i lived. I have a big ugly taylor spatial frame around my tibia so that it can be rotated into the correct alignment gradually over time. I should be out of the ebiking game for 2-5 months... but can't wait to be back.
 
neptronix said:
Oh wow, i mistyped. My big leg surgery was in 3 days ( as of writing then ).

I've had the operation and i lived. I have a big ugly taylor spatial frame around my tibia so that it can be rotated into the correct alignment gradually over time. I should be out of the ebiking game for 2-5 months... but can't wait to be back.
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What did they do to your leg?

Take your vitamin C and zinc, and get back in the game, yo. I hope your recovery is as painless as possible.
 
They cut the tibia in half, bolted an adjustable frame to the bone, and currently have a 2mm gap between both sections so that the bone is prompted to start filling in the gap... Then twist the bone while gradually compressing that 2mm of fresh new bone.

The cool thing is that its all computer guided using just a few reference points and a hexapod frame that can adjust on 6 axes.

Screenshot_20190220-072630~2.png

Ok, so why get such a crazy thing done? Well, i have had tibial torsion all my life, which means that one foot is rotated outwards by 10-15 degrees, causing a very biomechanically unsound way of walking and standing. I've used my kneecaps, ankles, and one hip excessively to soak up the bad angles and this has lead to early wear and tear of almost everything below the belt, but particularly my kneecaps.. i've been on a path to becoming slowly crippled for a long time.

It took me about 6 years of seeing specialist after specialist to find this out and a foot doctor and biomechanics lab were the final key in confirming my suspicion that the large assymetry was the cause of all the pain and loss of cartilage.

Bicycling has been the only thing that doesn't hurt my legs. I think this is because of the unloading effect, plus the fact that the angular deformity is less of a factor.. the crazy thing is that both knees have two distinct grooves cut into them. One formed by pedaling, another formed by walking. When i start pedaling, my knees make an audible pop and the kneecap becomes centered. Get off the bike and wwlk for a bit, and then there's another pop!

I think there is a good possibility of dodging multiple joint replacements in my 30's after this fix. Growth factor based drugs that grow cartilage are hitting the market in the next couple years as well. Somewhere in there is hope for not becoming wheelchair bound. The crazy yellow bike will absolutely be part of my recovery plan :mrgreen:
 
neptronix said:
They cut the tibia in half, bolted an adjustable frame to the bone,
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Yowch! That's serious work. Best of luck with it.

For that kind of trouble, I'd want some cyborg abilities thrown in as part of the deal.
 
Being able to run for the first time in my life is good enough! ( i wobble and move at half the speed of most people when i try )

It turns out i get to keep the rings and hardware after the surgery because of stupid laws preventing them from being recycled and reused, even though they're easily sanitized and designed so the part(s) that interface with the human body can be swapped.

So i'm thinking the top ring becomes a windchime and the bottom ring becomes a decorative part of the recumbent bike, haha.
 
Thanks for linking me to this Neppy. I'm glad the bike is working out well so far, and wish you a good recovery. Look forward to whatever motor (3T Leaf, right?) and battery improvements you do in the future! Now I just need to learn to be content with the discomfort of a regular bike seat for another year while I save money.
 
thundercamel said:
Now I just need to learn to be content with the discomfort of a regular bike seat for another year while I save money.
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A normal bike seat can be uncomfortable, but only if you're doing something wrong. Saddle too narrow, too wide, wrong shape, wrong angle, wrong height, too far from the bars-- any of those things can make it awful to ride. But that doesn't mean you you have to confine yourself to a wheelchair. Just do it right instead.
 
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