Slashdot Mirror
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."
But what about the sound - When I'm riding my bike, I don't want to listen to the constant loud, annoying drone of a motor.
Your Silence speaks more than words ever could.
We have motorized bikes here in England.
They're called 'Motorbikes'. We even have mini versions for teenagers called 'mopeds'. Clever, eh?
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.