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[evdjerome]

My neighbor from a couple blocks away has an identical Zero as mine. Except he's done some modifications to his as can be seen in the photos below. He's heading to the Vetter Fuel Economy Challenge.

[protomech]

That's Dr. Goff, right? He competed in the Vetter challenges last year too.

http://craigvetter.com/pages/2013-Challenges/2013-Vintage-Days-Challenge.html

[evdjerome]

Yep, that's Dr. Goff. I forgot to mention he says he is seeing a 17% increase in range since doing his Vetter mod.

[trikester]

Looks well streamlined for good mileage, just don't get caught in a strong crosswind!

Trikester

[protomech]

I would expect a little more of a range increase than that - though I hear the tail section is more important. I'm also curious about how much exactly the frontal area increases vs a naked bike w/ a rider.

[Doug S]

I agree with protomech, I'd expect more of an improvement with a full fairing like that. The range on my SR improved by an honest 20% (maybe even closer to 25%) when I added my Slipstreamer.

Maybe we're talking about different speeds? My informal testing was done on my commute, almost all of which is at freeway speeds. Certainly there's not as much to be gained at lower speeds by cleaning up the aerodynamics. Maybe he's cruising slower than I am, where improvements are harder to come by?

[ColoPaul]

I agree with protomech, I'd expect more of an improvement with a full fairing like that. The range on my SR improved by an honest 20% (maybe even closer to 25%) when I added my Slipstreamer.

Isn't a Slipstreamer just a big plastic windscreen?

[Doug S]

Isn't a Slipstreamer just a big plastic windscreen?

Yep.

[evdjerome]

I agree with protomech, I'd expect more of an improvement with a full fairing like that. The range on my SR improved by an honest 20% (maybe even closer to 25%) when I added my Slipstreamer.

Maybe we're talking about different speeds? My informal testing was done on my commute, almost all of which is at freeway speeds. Certainly there's not as much to be gained at lower speeds by cleaning up the aerodynamics. Maybe he's cruising slower than I am, where improvements are harder to come by?

Could be Doug. I don't know what speeds he got the 17% from. I think he mainly rides around town which is probably averaging around 35 mph.

[ColoPaul]

The range on my SR improved by an honest 20% (maybe even closer to 25%) when I added my Slipstreamer.
Isn't a Slipstreamer just a big plastic windscreen?
Yep.

20% is hard to believe.  Here's why I think that:  If Zero could get 20% improved range (170 miles is now 200+) by shipping the bike with $150 (retail) $30 (wholesale) fairing, why wouldn't they?  In the EV game where range means so much, what's $30? 
2kWh in batteries to get the same 20% range increase would add thousands to the cost of the bike.

[Doug S]

20% is hard to believe.

I had trouble believing it, too, but it's true. I have no reason to lie about it. Granted, it was a very unscientific experiment, but the aerodynamics of un-faired motorcycles are known to be very poor.

Zero DOES offer windshields. They're an extra-cost option. I didn't go with one of theirs because I wanted the biggest handlebar-attached one I could find that wouldn't add a lot of weight.

[Burton]

Shouldn't be hard to prove.

On the same day around the same time try this.

Remove the Slipstreamer and go out for a ride.
Pick a flat level area where you can go your highway speed long enough to get an wh/hr average.
Pick a "check point" and check the wattage and go home.

Put the Slipstreamer back on and repeat.

I plan on doing this a lot when I get my Vetter stuff on the bike. But it has to be done close together on the same day to remove other variables.

[Doug S]

Shouldn't be hard to prove.

I've thought a lot about doing the best controlled experiment I can rig up, but I can't really come up with a good reason to do so. I'm an EE, not a REAL scientist. It'd be nice to verify the real number, I guess, but I guess I'm not that big on the niceties.

What I CAN tell you, for sure, is that I used to limit my top cruising speed to 65 mph on the freeway, to keep from getting home with less than 20% charge after my commute (which Google maps says is 45 miles but my odometer says is 50). Since I installed the windscreen, I can now cruise as high as 75 mph on the freeway and I'm averaging 35% when I get home, assuming I don't make any side trips. Of course my commute isn't 100% freeway, and traffic prevents me from maintaining 75 mph the entire time I am on the freeway, but that's still a BIG difference, and I don't feel like everyone's trying to find a way to get around me any more.

[aelwero]

The range on my SR improved by an honest 20% (maybe even closer to 25%) when I added my Slipstreamer.
Isn't a Slipstreamer just a big plastic windscreen?
Yep.

20% is hard to believe.  Here's why I think that:  If Zero could get 20% improved range (170 miles is now 200+) by shipping the bike with $150 (retail) $30 (wholesale) fairing, why wouldn't they?  In the EV game where range means so much, what's $30? 
2kWh in batteries to get the same 20% range increase would add thousands to the cost of the bike.

I think this is a realistic estimate personally...  I made a small windscreen, basically an upside down triangle with the sides rounded to make it rigid, and that single square foot of plexi diverting air upwards off my chest made an actual noticeable difference at freeway speeds.  not only is it "growling" at higher speed, but the temp indicator takes around 30% more distance at max speed to turn on. 

As far as why zero doesn't ship with fairings, I totally agree with you that it doesn't add up.  It could be a marketing thing...  more folks might be amenable to buying them if they look more like a normal motorcycle.  Appearances are a big thing for vehicles.  hard to say for sure though

[Doug S]

As far as why zero doesn't ship with fairings, I totally agree with you that it doesn't add up.

My guess is that 1) the list price of the bike is already very high, and they didn't want to drive it any higher by including any hardware they didn't have to, and 2) if they offer the fairings as options, you can ride without one or pick the smaller or larger version. Owner's choice.