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Building a Better Motorized Bicycle
toyotaboy writes "Saw this in 'design news' magazine. It's a bicycle using an engine that looks like something pulled off of an R/C airplane. He uses a gear reduction system as well as a overrunning clutch to keep the engine running while stopped. Claims to get 20 mile range from its 1/4 gallon gas tank (80mpg). If you figure most engines like that are 30k rpm with 1:100 gear reduction, and an average bike rim is 26", you should get potentially 1,458,000 inches per hour, or 23mph! He goes on to say that similar devices in electric form (segway) fail because of their heavy 80lb weight and limited 10-15 mile range (and where do you recharge?) This thing can be filled back up at any gas station."
Can it run uphill? Small internal combustion motors have very slim power bands, and I didn't see anything about gear shifting, nor a torque assist.
Will it last? I'm no mechanical engineer, but spur gears and an overrunning clutch do not sound like overly robust components.
All in all, I wonder if a moped is a better buy.
I know a 50cc 2 stroke engine, which runs forever on on mere tea-spoonfuls of gasoline causes massive pollution. It's because of the release of so much unburned fuel into the environment (25 to 40% according to EPA estimates). Anytime you run a simple engine at such high RPM's you run into this dilemma. I've heard claims that a 2-stroke lawnmower running for 1 hour produces as many pollutatnts, (excluding CO2 of course) as 40 automobiles.
I'm sure this engine is much smaller than that, maybe 8 or 15cc's but still too much pollution for the energy created.
Who will get to 300 first, the MLB pitcher or the state of Texas?
tcd004
It seems to escape a lot of people that electrical outlets are far more plentiful than gas stations. Save for those people that work (or live) at a gas station, an electric vehicle doesn't involve any extra stops. Finally, in the amounts that an electric-assist bicycle uses, electricity is basically free (as in beer), which is less and less the case with gasoline.
If this engine isn't an emissions disaster, and isn't too loud, it may be very cool.
I have an electric power-assist (Currie) kit for my commuter bike. I use it for my 2 mile commute to work, and for running errands in a ~5 mile radius.
It's great- I can pedal hard if I want to, or take it easy and cruise at 17-18 mph if I don't want to sweat (like on my way to work in the summer). I'm not lazy- I run marathons and stuff- but I find that I use the bike more often for errands than I used to, pre-motor.
One of the only drawbacks is that the battery pack is heavy and awkward to haul up to my office to get charged every day. If I could get a kit with a *clean* gas engine, I'd be interested. But I have my doubts about this. For now, I'll stick with the clean electric (yeah, I know there are emissions associated with my bike's electricity consumption, but we're talking about 1 kWh per day).
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If this can be converted to a mini-diesel engine then it would be really attractive, Diesel gets better mileage which would increase the range and the fuel can be replaced with a biologically produced renewable resource, Bio-Diesel.
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I've been thinking about a "stepper motor" idea for a while, for a simple 21-speed bicycle where the motor *is* the front wheel.
Wow, that sounds like it would have plenty of torque.
a few UPS batteries, or even motorcycle lead-acid batteries
Check this company out for perhaps a better future battery: http://powergenixsystems.com/
War crimes, torture, lies, illegal spying... Would someone give Bush a blowjob, already, so he can be impeached?
80mi/g sucks.
Given the weight of a bike and what little it's transporting, it really shows that the engine is not very efficient.
Don't get me wrong. First, the idea is bound to be improved. Second, this combo is fabulous. You can use your bike normally. Or motorized. You get decent mileage. It's adaptable to nearly all current bikes, e.g. aftermarket part. And you probably have more access than a moped or motorcycle, although local laws vary widely.
But if anyone thinks 80mi/g is good for a bike with a motor needs their heads checked. Back in the 80s and early 90s, there were concept full-sized motorcycles that got well over that. The state of the art has gone quite a bit further along than back then too, given advances in frame design, engine efficiency, and lighter and stronger (albeit generally more expensive) materials.
I doubt, however, that people will widely adopt this. Part of the problem with bicycling these days isn't so much the effort; it's the roads. There are no separate lanes or even nice, wide lanes with decent shoulders. A lot of areas simply do not have roads conducive to safe biking, and a lot of bicycle riders don't follow the rules of the road. In Lancaster, PA, I use to ride a fair bit. I don't now. Traffic in my area increased drasticly, good driving dropped, and the weekend bicyclers had me irritated that I didn't want to be associated with the group--blowing through stop signs, riding two abreast or in the middle of the lane despite holding up traffic and having a clear smooth shoulder, etc. Drivers are typically dicks when sharing the road, but when bicyclers violate road rules, it's just all downhill from there.
I can't entirely agree with most of the objections I'm reading. I have ridden my bike a long distance to work, and can see the use for this product. Most days it's nice to glide along quietly smoothly, and environmentally friendily (if friend has an adverb form). After a long exhausting day, going home 3 hours later than normal, in the rain, all I wanted to do was get home. There was no joy in the ride; It was work that I wasn't looking forward to. To be able to get the bike up to speed and spend 25 cents in gas cruising home would have been a significant advantage. One that would inspire me to pedal the bike to work more often as the risk of an arduous ride home would be reduced.
But... If they want to sell me one of these kits they will have to be a little more fact-centric, and a little less like a Microsoft press release.
"With a quarter of a gallon of fuel, he says most bikes will have a driving range of about 20 miles."
Interesting, but what kind of mileage does the bike in the picture actually get? If you have a working prototype tell the story, and if it gets mediocre mileage tell us why, and what will be done to fix it in the version we buy.
"The problem is that it takes about 377 lbs of lead-acid batteries to equal the energy stored in a pound of gasoline"
Um, no it doesn't. At least not on my home planet. It's a shame that selling this item to the public seems to require such an obvious lie. Whatever cool formulas the chemists whip out aside, the forklifts at my client's work place use 350 lb. lead acid battery packs and run on them for 8 hour shifts. There is no forklift on the planet than can perform like they do for eight ours on 16 oz. (yes, I know that gas isn't the exact same weight as water, but it's close enough)) of gas. No way. Ain't happnin'.
"If you had to start the engine and then get on the bike, you wouldn't be able to get your balance," Katsaros says. "This gives users an easy way to get started."
Um, not so much. I started riding a motorcycle back when I had a full head of hair, and I can tell you for a fact I can reliably "start the engine, and then get on the bike." And, more usefully, other bikers and I can start the engine and engage it without duck-walking the bike up to speed so we can "get our balance." The feature of disengaging when the bike is going less than two miles an hour is there to avoid all the low-end gear + clutch crap that is necessary to to get a motorcycle going from a stop and still yield decent efficiency at normal speeds. It's a compensation for the simplicity of the design and a good trade-off in the cost/weight/functionality game. It's not a "feature for the benefit of the inept rider" any more than Code Red was a "security assurance feature for WindowsNT admins."
I sure hope Mr. Katsaros understands that selling a geeky toy means marketing to geeks, who by their nature prefer facts to hyperbole.
They say they get 80 mpg from this at up to 23 mph? Big deal. I consistently get 60 mpg from my 1100cc BMW motorcycle, with two people plus luggage, as long as I don't go over 70 mph or overtake aggressively.
Smaller engined conventional motorcycles (under 250cc) get 100+ mpg.
What I don't get is why every other "new" invention bashes electric by saying "this will tide us over till batteries get better and with gas you can fill up anywhere" I thought the whole point is to get away from gas once in for all. I have a good idea, how about spending a little more time and money on research on electric instead of fiddle farting around with glorified weed-whacker engines so we don't have to wait around. His claims of 85lbs for electric bikes are a bit off. They make NiMH electric conversions in the neighborhood of 20lbs. That's only ten pounds heavier than his "petite" 2 stroke. No gas or oil to mess with, no noise, no fumes, and nothing to have to tune up, just plug the thing in and go. I would also like to know where he rides where there is no electricity? Does he plan on using his bike for the two-hour commute into LA on the 405 during rush hour? Who would be willing to ride on a mountain bike for reasons other than sport far enough to actually run out of juice in the batteries, much less gas for his version. So range isn't really an issue since you could plug the thing in just about anywhere. This is another example of another fine product to "revolutionize" the world, as we know it. What this inventor has yet to figure out is those that are already willing to ride a bicycle to work are already doing so and that within a short period of time get in good enough shape to pedal it their damn selves, and don't need the extra weight and cost to get them up to the top of those theoretical "hills" these inventors always ramble on about as being the big determining factor as to why people don't ride bicycles. Here is a little clue for him, people who are too lazy to even pedal ten miles on a bike are certainly not going to want to even ride the same distance on a powered one. There's no heat & no AC for one, no protection from the elements, no comfortable bucket seat to park their fat ass in, no cd player, and where the hell are they going to plug in their cell phone and where are they going to put their McDonalds value meal #2 at along with all their junk they drag around with them? On top of that he hasn't even figured out the idea has already been done a thousand times, and that no one wants it. Don't take my word for it just look in the back of Popular Science or Popular Mechanics magazine you find half a dozen conversion kits "that if you order now you'll get free shipping". Aside from having no clue I do give this guy bonus points for finally containing everything in the hub instead of the ridiculous bolt on contraptions some people have come up with electric or gas.
Actually, there was a two-wheel-drive bike. I forget who made it now, possibly Honda. It had hydraulic motors on each wheel, and the engine drove a small hydraulic pump directly.
Here here. Bicycles have peddles. Use them, get healthy and see the world.