Why not comfort bikes?

General Discussion about electric bicycles.
john61ct   10 MW

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Re: Why not comfort bikes?

Post by john61ct » Nov 14 2019 12:59am

neptronix wrote: i only build bikes with 22" wheels or smaller these days
Well for mainly dirt / gravel desert & forestry tracks I just can't see going that small.

Fattie tires is suspension, so maybe 24" rim, gets to what circumference?

And I fully agree with "comfort bike platform" as opposed to the usual competition MTB or road bike frames in the US.

But as stated need to be able to stand on the pedals, any recumbency is a non-starter, not included in **my** definition of "comfort bike"

And I'm including big cahuna DD in my plans, in fact the main driver most of the time.

Just with heavy loads and big hills, see the need for a motor using gearing **as well** to help with slow speed high torque, since I **can't** get down too small a wheel, and even a 4000W DD chokes at those low speeds.

The CA v3 is indeed there to prevent damage only, up to me to be conservative to stop, get out, empty the water jugs maybe push the rig up to the top of the pass.

From here it seems going to the extra cost / complexity of multiple motors is worth it, probably an ICE motor is the only alternative.

> This is a 30mm wide DD ( 14-15lbs ) in a 20" wheel in a semi recumbent frame going up a 10% grade for 11 minutes straight. That's a pretty hardcore climb, and probably beyond what you're trying to do.

Not at all, and I'm hoping to get to at least 400lbs as well.

> you rarely see rear suspension on those kinds of bikes, which you really need, since more of the weight sits on the back of the bike than usual

Have not decided yet where the cargo / big battery pack(s) get distributed, with a front DD obviously would need to load up at that end.

A Rohloff Speedhub optimized for the lowest end is prolly a folly, 130 Nm limit I've heard?

Is there a mid BB drive that gets up to higher torque than that, could be derated for headroom with CAv3?


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neptronix   100 GW

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Re: Why not comfort bikes?

Post by neptronix » Nov 14 2019 1:12am

john61ct wrote:
Nov 14 2019 12:59am
neptronix wrote: i only build bikes with 22" wheels or smaller these days
Well for mainly dirt / gravel desert & forestry tracks I just can't see going that small.

Fattie tires is suspension, so maybe 24" rim, gets to what circumference?
22" is a typical motorcycle wheel size that translates to 18" in motorcycle tire diameter.
Those things handle rough roads pretty well. But they have real suspension. I don't build bikes without real suspension either. It's mandatory with small wheels, and i'd argue at the speeds i go at times ( 30-50mph ), it's even mandatory with 700c/29er wheels.

You would not want to run a suspensionless bike on very rough roads at even low speeds, especially on a comfort bike where it will deliver even more of an ass pounding than a regular MTB would due to the weight distribution. 30lbs of motors would compound the problem, and also, geared motors get destroyed fast in offroad situations, especially on hardtails where the gears are taking huge axial loads. Not a problem with a DD, you just have to worry about the side cover bearings.
Just with heavy loads and big hills, see the need for a motor using gearing **as well** to help with slow speed high torque, since I **can't** get down too small a wheel, and even a 4000W DD chokes at those low speeds.
I proved in 2011 that you can climb 12% grades when i was 100lbs heavier than i am now using 20" wheels and a motor rated for only 1000w. How much weight do you need to pull up what grade, and can you give me an example motor simulator link of a motor overheating in that situation?

Yes gearing would be nice but remember that bike chains are only really designed for perhaps 500w of power. A very high power mid drive is going to turn every drivetrain component into a maintenance item. A rohloff also costs something like a thousand dollars so you're looking at a bike that is very expensive to run and build if you go that route.
"Love and compassion are necessities, not luxuries. Without them, humanity cannot survive." - Dalai Lama

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

Balmorhea   100 W

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Re: Why not comfort bikes?

Post by Balmorhea » Nov 14 2019 1:35am

neptronix wrote:
Nov 14 2019 1:12am
I don't build bikes without real suspension either. It's mandatory with small wheels, and i'd argue at the speeds i go at times ( 30-50mph ), it's even mandatory with 700c/29er wheels.
Why do you go so fast? Do the local authorities make you register your bike?

My newest e-bike is the fastest one I've had yet. It keeps pushing to over 30mph, though it needs plenty of help from me to maintain that speed. But I find that my favorite cruising speed is about the same as that of my earlier e-bikes, 18mph give or take. That doesn't change much for me regardless of street situation or prevailing traffic speed. The surface always needs adequate inspection, and I always want the ability to exercise whatever options I have before the moment is lost.
A rohloff also costs something like a thousand dollars so you're looking at a bike that is very expensive to run and build if you go that route.

A Rohloff hub wholesales for substantially more than a thousand bucks now, so there's that. I guess "substantially more than a thousand bucks" is the new five hundred bucks.

However, it's a surprisingly cheap hub to run. Sprockets are expensive (for sprockets), but they last a long time. And they're reversible. Fluids are infrequent to replace, and maintenance is not labor-intensive. Compared to new-hotness 1x11 and 1x12 cassettes and chains, it's very economical overall.

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MadRhino   100 GW

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Re: Why not comfort bikes?

Post by MadRhino » Nov 14 2019 1:58am

Some older dirt bikes are on 16 or 18’’, but they have much better suspension than bicycles. Even 24’’ on ebikes are making a harsh ride in mountain trails and force you to slow down. 26 is good with 2.6 to 3.00 tires making them 27 or 27,5’’ OD. Recent MTB are on 29 and everyone agree they are a much better ride.

I find 24’’X3.0 are perfect for the streets here, with all the rough pavement and potholes. Smaller is good only on nice surfaces.

Tires are not making suspension. It is about time that people forget about this myth. Fat tires are bouncy and fragile, absolute sh*t to speed on the rough. They are made for riding slow, on soft surfaces ideally. On the street they are not that bad at low PSI, max 40 mph with good ones. Faster, they are a serious risk.
Make it fool-proof, and I will make a better fool.
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Balmorhea   100 W

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Re: Why not comfort bikes?

Post by Balmorhea » Nov 14 2019 3:33am

MadRhino wrote:
Nov 14 2019 1:58am
Tires are not making suspension. It is about time that people forget about this myth.
I think suspension is no substitute for good tires and appropriate speeds. It makes a bike capable of high speed, but at the cost of making it ride lousy all the time.

Would you wear 6" travel shoes every day? You wouldn't. You'd think, "walking in these things sucks.".

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neptronix   100 GW

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Re: Why not comfort bikes?

Post by neptronix » Nov 14 2019 9:51am

Balmorhea wrote:
Nov 14 2019 1:35am
Why do you go so fast? Do the local authorities make you register your bike?
There is no way to legally register my bike but local authorities always turn a blind eye. I am always pedaling and it does not register in their mind that i'm doing anything other than riding a bike. I also design my ebikes to not stick out. No duct tape, little to no exposed wiring, controller tucked in a bag or otherwise hidden, etc.

My speeds have to do with the poor design of the streets where i live. I am a commuter and we have bicycle lanes that randomly appear and disappear. Or people park in them. Or people put trash cans in them. Sidewalks appear and disappear also.

In addition to this, we have basically nobody commuting by bicycle in this area. Drivers are not used to looking out for bicycles. If you follow legal bike speeds and legal riding rules, you will be constantly weaving in and out of the car lane and will put yourself in extreme danger. I know this because i've had stints of riding a non powered bike out here and each ~5 mile ride had multiple times where nobody was paying attention and i could have been killed if i wasn't looking. Everyone i've spoken to, including people at bicycle shops, tell me that the idea of commuting by bike here is insane. :lol: I suppose i agree.

My solution is to have a bicycle that is capable of occasionally maintaining the top speed of surface streets, and that's 45mph. Meaning that when the bike lane is about to disappear, i've already flipped a speed switch and decided i'm a motorcycle until i have a bike lane again. And apart from the occasional scream to "get off the road", cars treat me as a motorcycle when i'm traveling at the speeds they're going.

Then i get back in the bike lane when it's safe and putz along at 20-30mph.
The surface always needs adequate inspection, and I always want the ability to exercise whatever options I have before the moment is lost.
Does this mean you ride a bicycle without suspension and constantly scan the road for imperfections? cuz that's one thing i hate about suspensionless bikes the most. A low level anxiety intrudes into the ride at all times. Much better to have a couple inches of nicely damped ( air, oil ) travel, and not have any cares at all about the road, other than mondo potholes.

No tire can replace what a nicely damped shock can do. On a fat bike, you deflate your tires and incur a huge friction penalty, which gives you at most, 1-2 inches of undamped "suspension".

A slightly deflated fat tire will give you as good of suspension as the $10 spring on this really crappy folding bike.

Image

Which is fine if your road surfaces are consistently nice and smooth and that's all you really need, but..

Look at the MTB spring they put on this Cannondale Easy Rider. It's 3 times as long and has a damper. You can basically forget about experiencing a bump in the rear of the bike, which is great because something like 90% of your weight is resting there. :)

Image

No tire can do this.
Balmorhea wrote:
Nov 14 2019 1:35am
However, it's a surprisingly cheap hub to run. Sprockets are expensive (for sprockets), but they last a long time. And they're reversible. Fluids are infrequent to replace, and maintenance is not labor-intensive. Compared to new-hotness 1x11 and 1x12 cassettes and chains, it's very economical overall.
The problem with a very high power mid drive is not just the sprockets going out, but pretty much everything that transmits power. There isn't a single aspect of a bike drivetrain that can handle, say, 4000w. You'll destroy internal geared hub internals, derailleurs, chains, sprockets, even your right chainstay.

The problem with a very high power DD hub is..... it's heavy :lol:
"Love and compassion are necessities, not luxuries. Without them, humanity cannot survive." - Dalai Lama

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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neptronix   100 GW

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Re: Why not comfort bikes?

Post by neptronix » Nov 14 2019 10:10am

Balmorhea wrote:
Nov 14 2019 3:33am
I think suspension is no substitute for good tires and appropriate speeds. It makes a bike capable of high speed, but at the cost of making it ride lousy all the time.
I have never experienced anything other than a massively improved ride quality over a hardtail from a properly adjusted shock. I'm not sure where you are getting this from.

Even the shitty downtube folder i owned ( seen above ) with 20" wheels rode better than my 26" hardtail along broken pavement. And all it had was a horrible spring.

I have never encountered any kind of hardtail bike that rides well, other than a long cargo bike with a chromoly frame that flexes like a sketchy bridge when you hit irregularities, and also distributes your body weight more to the center of the bike. But this kind of bike has the wheelbase of a compact car and feels like piloting a bus :lol:

A 'comfort bike' that puts another 10-20% of your weight on the rear wheel trades road impacts to the wrist, shoulder, and neck, to impacts to the spine. Rear suspension mitigates the spine issue.

A suspensionless semi recumbent bike is actually an improvement over the comfort bike for your spine. The lawnchair style seat distributes your body's weight much better, and generally they come with a very fat padded seat, and the rear of the seat also has some elasticity in it.

You can put a super fat padded seat on any upright bike, but generally the problem is that the more padding, the more your pants will rub on it and you'll turn your pants into a maintenance item. Not a problem on a recumbent or semi recumbent bike, because your legs are facing forwards, not down.
"Love and compassion are necessities, not luxuries. Without them, humanity cannot survive." - Dalai Lama

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

donn   1 kW

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Re: Why not comfort bikes?

Post by donn » Nov 14 2019 11:32am

I'm not so sure a lot of padding is what you need down there, though. You need enough and no more, like a good motorcycle seat. My favorite is actually one with no padding at all, it's just a sling, kind of classic lawn chair style.

I guess really this whole discussion is kind of silly if it doesn't take into account the differences we see in bicycling. Would a classic racing bicycle be better off with fat tires or suspension? Ha ha, no. Mountain bikes, recumbents ... seats, tires, suspension, motors, gearing ... no answer that works for all. For me, in particular the game changed with respect to suspension when my average speed went up by only about a 5mph, but that's riding in a particular urban area. If I'd been riding on rougher roads, would have happened sooner I imagine. If I'd been riding an upright bike where I could absorb shock with my legs, maybe that would have made a difference ... or maybe not. At higher speeds, it's nice to have somewhat consistent contact with the road, and suspension does that better than occasionally riding out bumps by standing. I gather fat tires do that too, improve road contact, and when riding at the speeds some of us are talking about here, it's worth a look at what kind of rubber motorcycles wear.

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Re: Why not comfort bikes?

Post by Balmorhea » Nov 14 2019 3:14pm

neptronix wrote:
Nov 14 2019 10:10am
Balmorhea wrote:
Nov 14 2019 3:33am
I think suspension is no substitute for good tires and appropriate speeds. It makes a bike capable of high speed, but at the cost of making it ride lousy all the time.
I have never experienced anything other than a massively improved ride quality over a hardtail from a properly adjusted shock. I'm not sure where you are getting this from.
When you introduce all the mush, slop, geometry change, flex, and pedal bob of suspension, a bicycle no longer feels like a bicycle. At that point it's just a flimsy little motorcycle. Comfortable, maybe, but not so much as a car. And it's no longer doing what the bicycle does best: using the minimum to yield the maximum.

Like I asked elsewhere, where are your linkage suspension shoes, if this stuff is so good?

I often observe that a bicycle is a machine, but it's also like a musical instrument, sensitive to subtleties of setup and the user's technique. So if a regular bike is like a guitar, a suspension bike is like a laptop with Garage Band installed. Easier, maybe. But less satisfactory in pretty much every way that matters.

For the sake of a bigger performance envelope, I'm willing to accept the compromises of adding a motor and battery. But those things mess up a bike less than suspension does.

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neptronix   100 GW

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Re: Why not comfort bikes?

Post by neptronix » Nov 14 2019 3:43pm

Yeah there's a lot of variability in our physical needs and riding conditions. So of course there's never much agreement on here. :)

if you have flattish roads and a crappy road is only a random occurrence, I get why suspension would be an afterthought.
I did live in an area like that and had an ebike that did up to 30mph. I rarely took it to that speed, but exceeded that speed going downhill a few times. There were a few times where i'd hit a bump going downhill and my front or rear tire would lift into the air and land in a place i didn't expect. So if suspension is not a comfort issue, it may be a safety issue.

I've lived all over the United States by now and Utah is absolutely the worst place to commute on a bike, period.

My needs are pretty extreme and i understand i'm basically asking for a bike that's sometimes a motorcycle with pedals, other times not. A do it all bike is kinda cool even if you don't need it though. :thumb:
When you introduce all the mush, slop, geometry change, flex, and pedal bob of suspension, a bicycle no longer feels like a bicycle. At that point it's just a flimsy little motorcycle. Comfortable, maybe, but not so much as a car. And it's no longer doing what the bicycle does best: using the minimum to yield the maximum.
You're describing a full suspension bike with a poor rear linkage design and incorrectly tuned shock. Perhaps a bike from walmart, or just a cheap or otherwise poorly maintained one?

Come over here and give my cannondale recumbent a spin. it's faster, more comfortable, and handles better ( at speed ) than anything you've ridden. It's the Mercedes Benz of bicycles. It does not have a millmeter axial of slop in the rear. It does not pedal bob or waft about. You just drop off a 4 inch curb, hear the sound of the rear tire thumping the pavement, and keep on pedaling like nothing happened. The build quality is so good that you can even feel it in how well the bolts slide in and out of the frame. Made in the USA and built to last and take a beating :thumb:

I also had a Turner 02 ( FS with air/oil dampers ) previously, originally a $4000+ bike. Paid $250 on eBay for the frame and built it up. It had a better ride quality than my luxury sedan and i tuned the bob out of the rear shock. It would roll over a pothole like nothing. I had ultra low friction 26 x 2.15 tires on it and it was a hair less quick than my roadbike. I put a 6kW motor on it and it was a blast and STILL never had any weird motion/slop in the frame. It only felt uncertain as i crossed the line past 50mph, while rolling over terrain that's uncomfortable to drive on in my luxury sedan. *that's what a good FS bike is like*.

I got my semi recumbent and never looked back and still kick myself for playing with upright bikes since.
"Love and compassion are necessities, not luxuries. Without them, humanity cannot survive." - Dalai Lama

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

donn   1 kW

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Re: Why not comfort bikes?

Post by donn » Nov 14 2019 6:48pm

Balmorhea wrote:
Nov 14 2019 3:14pm
I often observe that a bicycle is a machine, but it's also like a musical instrument, sensitive to subtleties of setup and the user's technique. So if a regular bike is like a guitar, a suspension bike is
... it's like another kind of guitar. There's small and large, steel and nylon string, archtops where the bridge operates on the soundboard in compression and flat-tops where it's under tension; some guy coincidentally was interested in my recumbent last weekend and starting telling me how he's re-inventing the guitar with tuners down at the bridge for a lighter better balanced guitar (though I think he knows it's been done.) There's 4 string tenors and 7 string Brazilian guitars that play the bass line in a choro band, baritone guitars with a long scale, and every kind of tuning, and Cuban things that may or may not be guitars. And of course there's acoustic and electric, acoustic electric and magnetic electric. Walk into a playing situation with the wrong kind, and you have a piece of junk. Get on the internet and tell someone they have the wrong kind, and ... it's hard to know what to make of that.

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Re: Why not comfort bikes?

Post by Balmorhea » Nov 14 2019 7:14pm

donn wrote:
Nov 14 2019 6:48pm
Balmorhea wrote:
Nov 14 2019 3:14pm
I often observe that a bicycle is a machine, but it's also like a musical instrument, sensitive to subtleties of setup and the user's technique. So if a regular bike is like a guitar, a suspension bike is
... it's like another kind of guitar.
Autoharp. Technically, you can make music with it, just not good music.

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MadRhino   100 GW

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Re: Why not comfort bikes?

Post by MadRhino » Nov 15 2019 1:30am

Yep. When you have a stiff frame with the best suspension components, it does ride much better than cheap motorcycles, with a fraction of the weight.

I top around 70 mph, hit 60 at least once everyday, with frequent 0-45 hard accelerations in my commute. And been doing so for many years, never less than 20 miles a day, more often 40. Lots of mileage done. Perfect ride. I wouldn’t go back to motorcycles if they were free. You need to spend a lot of time and money to build a good performance bike, but that is an investment that you never regret.
Make it fool-proof, and I will make a better fool.
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Street: https://s20.postimg.org/ewrvugywt/Session_04_2015.jpg
Dirt: https://s20.postimg.org/lbqwr55ml/IMG_0157.jpg

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