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Discussion Starter #1
so i took a long drive down to san diego this weekend....and at some points gas (regular unleaded) was topping 4 bucks....

anyway, on the drive back up i started thinking...if the biggest problem with the all electric cars is the batteries not holding enough charge for longer distances, why not just add a little (under 100cc) 4stroke electric generator to continually charge the batteries as you are driving?

it seems if you could keep the batteries charged, you could drive VERY long distances for VERY little gas....(i'm imagining the scene in dumb and dumber when they drive to aspen on the mini-bike!)

...i know there must be a good reason against this.....but i can't think of why......this way just seems to make more sense to me...the small amount of gas helping the electric, rather than the opposite which is currently considered "hybrid technology"...
 

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Go over to caferacer.ca Theres a good piece on a guy who built a hybrid. Check it out.
 

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Uhhhh....people...that's what the hybrids are that are being sold right now. They are gas/electric hybrids.
JohnnyB
 

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Discussion Starter #5
the hybrids being sold now are MOSTLY gas, with electric motors helping out, giving them slightly higher fuel economy...but what I'm thinking about is MOSTLY electric, with gas helping out...there is a big difference in terms of the amount of fuel used.

...after a bit of research I found the term PHEV, which stands for plug-in hybrid electric vehicle...this seems to be very close to what I'm thinking of...it runs the first 25-50 miles in all electric mode, then the gas engine kicks in.
 

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Believe me, that tiny gas engine, mostly electric cars are out there already, in numbers, just not popular in the US. The Prius is about a 50/50 split.
JohnnyB
 

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See my previous post. The guy built a bike just like you are talking about. And he'll be glad to talk to you about what he did.
 

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the chevy volt due out in 2009 is an electric car with a gas generator. The gasoline engine does not drive the wheels at all. It is exactly what you are thinking of. It is also not really a hybrid but an electric car. My father is really low on the list to get one (one of the first 2000) so we went to the unveiling at the NY auto show.

The current hybrids use the electric motor to drive the car, mostly in stop and go situations, and when the batteries hit a certain level the gasoline engine kicks in and drives the car while the charging system replenishes the supply of electricity. It is not a true electric vehicle (hence the term hybrid) but the electric motor is the primary means of propulsion.

to relate this to motorcycles, it is possible to build a mototrcycle in this layout but the biggest issues are space and weight.

despite what people are saying about biodiesel not being friendly ans what not, a motorcycle is probably the ideal vehicle for a diesel conversion. There are several diesel motorcycles already in production and most of them see a range of 100 miles per gallon (see cycle world from two months back). There is a site on the web where a guy shows you how to build a royal enfield that is powered by waste vegitable oil. Not a very fast bike but it is really conservative with fuel and the best part is you can build it at home.
 

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you can't get something from nothing.
hybrids are only more fuel efficient than conventional care in the city driving (stop and go) mode. that's because they are returning energy into the batteries when you slow down (instead of making brake pads and discs get hot and thus wasting it). on long highway trips, they are marginally more efficiant due to their slightly better aerodynamics. for long highway trips, there are some cool small displacement (and size) diesel cars which get 75 mph+ when driven around 50 ( not 80...drag increases with the square of the speed...) less air moved harshly, more mpg.
for bikes, there is the e-go. fully electric (plug-in) with regenerating deceleration. it's a scooter format but you can't get around these days for less $ (once you've bought it). it may be the only two wheeler i've ridden which g-to hasn't (yet).
-parks
 

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Thou shalt not abuse the laws of thermodynamics.

It takes a certain amount of horsepower for a vehicle to go a set distance in a set time, regardless of the kind of motor that's being used.

Now, electric vehicles offer higher efficiencies than comparable gasoline/diesel motors, especially for stop/go driving. All the torque an electric motor can provide is available from 0rpm to the motor max. This isn't true for gas motors, and so you lose efficiency at low rpms.

The Chevy Volt does indeed work just like you mentioned - the gasoline motor in this vehicle is efficient because it only has to run at one speed, and so therefore tuners can get the most of the motor that way.

However, work = force x distance. You need the same amount of work out of an electric motor that you'd need out of a gas motor to move your car a set distance. The difference is in the efficiency. A 100cc motor isn't going to be able to drive a generator capable of running the car at the same rate that a 3000 cc motor is. Generators take power, too. Plus, you have losses due to resistance, friction, etc.

What the Volt does is make the driving process more efficient: it charges up overnight in your garage, and moves the cost of gas to your electric bill instead. Since this is much cheaper, you save cash. Then, because electric motors are much better at stop-and-go driving (more efficient, less loss) you save energy driving around town.

However, on long-distance drives without stop-and-go driving, where you're not able to charge the battery overnight, you won't save much more on gas than you would have with a comparably-designed car with an efficient gas motor.

EDIT: You know, I bet if you drove the Volt hard enough, you'd be able to drain the battery faster than the generator can charge it. Wonder what the electric controller in the Volt does then? Does that generator have the power for full-demand driving? I bet not.
 

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Geeto - awesome link.

Take a good look at that link, you dirtbike guys out there - that right there is the future for all off-road bikes. We're losing ground all the time to development and noise, and the EPA.
 

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what is so very comical is that these currently available "green friendly" hybrids have been proven to have a larger carbon foot print than full size SUVs

over their entire lifespan

also comical and insulting is that for years....... not sure if currently

if you bought a gas hog SUV or truck with a 7000 pound GVRW or higher

Uncle Sam would allow you to write off, 100%

the entire purchase or lease price in one year's tax filing

however....... if you buy a hybrid

you are only allowed to write off or deduct the price difference between it...... and the standard base model

in the case of the Honda Hybrid which does indeed have a larger carbon foot print than the gas hogs and the base model

but is ignorantly viewed as environmentally beneficial

about 2000 bucks

whereas if you bought a loaded Surburban or whatever

30, 40, 50K plus

bizarre huh?

btw........ daytona and colorado just passed noise laws banning LOUD motorcycles

not just loud vehicles period........not loud factories........ not loud duallys with 4-5 inch open exhausts

loud bikes

very discriminatory

reality is that fuel efficient motorcycles should be offered tax incentives for riders and owners

what the heck is wrong with the masses and our idiot politicians?
 

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Marketing to the guilt-ridden is a lucrative scheme.

Give me a good little turbo-diesel, I'll have great mileage, low cost, and good reliability. Volkswagen and Honda are finally bringing clean diesels stateside, which is great news. I'll take one of those over a Prius any day.
 

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FWIW, Volvo and Saab have partnered with a couple other Swedish technology firms to develop and offer a new series of PHEVs, starting with the C30. They do have prototypes driving around now. They are in fact fully driven by electric motors, at each wheel. I can't remember now, but aside from the obvious advantage of AWD, I think they use the motors for braking too, which makes sense to me. The engine is a generator, but I'm sure it's more than 100cc's.
You can read more about it here;

http://www.greencarcongress.com/2007/09/volvo-to-show-f.html


FR
 

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you can also think about locomotives. They use diesel power as their generators to power the electric driven wheels. The thing that is different is that the throttle on a locomotive revs up the diesel engine which provides enough juice to propel the cars. GE is one of the leaders in rail transportation...im guessing they would have some info about their set ups online, since they have commercials touting how clean their trains are...
 

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When you include electrical transmission losses in the calculations then any vehicle you have to plug into a socket is less efficient overall than a high mileage car like a civic. Remember, when you plug in and start charging from the coal powered generating plant 100 miles away, numerous substations and transformers you lose about 20% efficiency right there.
But then it's not about reducing pollution, it's about MOVING the pollution away from tree hugging voters and into the sparcely populated areas where rednecks live...cause they deserve to die anyway.
JohnnyB
 

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Many years ago when I worked for a large computer company, a few employees tried to start a project study (1985 era) with exact concept of a small engine/generator driving electric motors on all wheels. The concept was to eliminate brakes and a transmission from the car design and ultimately reduce the number of moving parts under computer control. I was one of those employees on that design study group.

We were unsuccessful in getting the company to invest in this technology study and turn it into a real project. Part of our failure was were where all junior employees and lacked the knowledge to convince the upper management the value of this project. Of-course no-one at that time could foresee the value of creating a more efficient auto. - This computer company is no longer around and we now are paying upwards of 4 dollars per gallon.

As of today, we still have a bunch of dipsticks for politicians and the US is so far behind the curve on this technology that we are now depending on some foreign country to build and sell us this technology.
 
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