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Discussion Starter · #1 ·
I'm kicking around the notion of either a EV car or bike. I need a bike to be able to do 60mph and 50 miles. What would it take to build something like this in a bike? I assume regen would certainly be needed.
 

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Discussion Starter · #3 ·
Brammo's empluse is the only thing that would even fit my requirements at $14K. $14K would certainly purchase batteries, motor, and controller for a project. Plus pay for charging the bike for a while. Fabrication isn't an issue to me at all. I've built a Suzuki samurai with a VW turbo diesel, twin t-cases, and a host of other mods.
 

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Besides the obvious, (bike chassis, motor and controller) what's needed is an adequate amount of energy storage for the job. Depending on the speed at which the 50 or 60 miles will be covered, that will vary. Perhaps someone could post some motorcycle energy consumption figures to help you make the calculation. I would guess 8 kWh might be adequate.

Popular DIY batteries include Thunder Sky (now Winston Battery) and (Headway). There are a few other battery possibilities as well.
 

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energy consumption per mile..
Agni motored Aprilia sportsbike, 130kg. best 70wh/m worst 145 wh/m

Dual Agni motored TTX02 175kg. Best 100 wh/m worst 300wh/m (well, it is a race bike)

Should give you an idea.
A 7KW/H pack will give you some headroom as long as the bike isn't too powerful.


Steve
 

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What about ems's GPR-S? I think you could get Empulse performance for much less. There is a 09 left over stock in the "opportunity buys" section for $3500 that only needs batteries. Even if you go with their 72v 100ah lithium battery kit you are only adding ~$4500. Should be close to Empulse performance at a fraction of the cost, and better yet, you don't have to wait to buy it.
 

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Discussion Starter · #7 ·
What about ems's GPR-S? I think you could get Empulse performance for much less. There is a 09 left over stock in the "opportunity buys" section for $3500 that only needs batteries. Even if you go with their 72v 100ah lithium battery kit you are only adding ~$4500. Should be close to Empulse performance at a fraction of the cost, and better yet, you don't have to wait to buy it.
Honestly for $8K, I'd rather fabricate something and get better performance. I don't count my labor when it comes to stuff like this.
 

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energy consumption per mile..
Agni motored Aprilia sportsbike, 130kg. best 70wh/m worst 145 wh/m

Dual Agni motored TTX02 175kg. Best 100 wh/m worst 300wh/m (well, it is a race bike)
At what speeds? Exponential wind resistance is a bitch.

I've been looking for info on the consumption of an aerodynamic electric bike at highway speeds for a while.


The E-Tracer (electric Ecomobile / Monotracer) electric cabin bike got 123 watt hours per mile from LA to Vegas - http://peraves.wordpress.com/2010/11/01/e-tracer-at-sema-show-in-las-vegas/
Quite possibly not what patracy is looking for, though.
 

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They were min and max figures obtained from real world experience with a number of bikes, not hyperthetical figures of power draw cruising at a fixed speed.
Obviously the twin motored bikes have more power to waste and reach higher speeds in use, as well as being significantly heavier.

Speeds reached on single motor were 85mph max, twin motor maybe 110mph max, but these were peaks in normal driving circumstances, and will serve as a good baseline for bikes of similar weight/power (and efficiency of course).

Etracer is completely streamlined "velomobile" and not really a decent comparison with a regular motorcycle.
Cedric Lynch's "Velomotorbike" can achieve some 150 miles from what I believe is a 4kw/h pack, cruising at speeds over 50mph. This is around the same wh/m as an electric pushbike at 20mph!

Steve

At what speeds? Exponential wind resistance is a bitch.

I've been looking for info on the consumption of an aerodynamic electric bike at highway speeds for a while.


The E-Tracer (electric Ecomobile / Monotracer) electric cabin bike got 123 watt hours per mile from LA to Vegas - http://peraves.wordpress.com/2010/11/01/e-tracer-at-sema-show-in-las-vegas/
Quite possibly not what patracy is looking for, though.
 

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It certainly would be interesting. But seeing the design and all that CF makes me think $$$$$$ :eek:
Oh, yeah, the ICE Monotracer is crazy expensive, something like $77,000. I'm sure the E-Tracer with all the lithium ion, and A/C motor and controller, will be even more so. And I believe that's with kevlar, not carbon fiber. Uses a BMW K1200S engine.
 

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They were min and max figures obtained from real world experience with a number of bikes, not hyperthetical figures of power draw cruising at a fixed speed.
That's not very useful. For all I know, what "real world" means to you is wondering around at 20mph with no stops.

Measured consumption cruising at 65mph would probably be most useful to me.
 

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I'm kicking around the notion of either a EV car or bike. I need a bike to be able to do 60mph and 50 miles. What would it take to build something like this in a bike? I assume regen would certainly be needed.
Since it hasn't been said yet: Regen doesn't seem to be very helpful.

The team that won the main stream category of the Automotive X-Prize competition decided that they would be able to get better efficiency out of gas than electric partially due to the lack of usefulness of regen at the low weight of their vehicles.
 

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That's not very useful. For all I know, what "real world" means to you is wondering around at 20mph with no stops.
:D Jozzer has had a big hand in building and maintaining the TTXGP bikes. He may have been limited to 20 mph in the pits, but the rest of the time the average speeds were a little faster than that.

For what it's worth, my 130 kg Cagiva gets anything from 70 to 120 Wh/mile in much more sedate city riding.
 

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My Series wound DC motor in a 1986 Honda VFR at 50mph was between 90 and 100 wh/mile. Estimate about 100-125 for a build at 60mph.

If you have doubts, there is a nice calculation sheet on Lennon Roger's Electric motorcycle website, and it has been pretty dead on with what people are getting, and it matches what the Brammo Enertia uses per mile.
 
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