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[sendler]

This shows clearly that when streamlinig a truncated shape that half the improvements can be lost at the back.
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[Richard230]

Speaking of aerodynamics: last week I rode my Zero to my daughter's house, located 37 miles away, as the road turns. (1/3 freeway travel and 2/3 surface roads).  I take this route about twice a month and drive the same way each time.  The only variation is wind and traffic, but it makes very little difference to the amount of power used during my rides there and back.  Typically, it takes between 30% and 32% of my PT battery capacity to go that distance.

Last week I needed to carry a weather station over to her home and installed a Givi 37 liter top box on my bike's rack. The top box could not even be closed as I had to strap down the lid since the station was too bulky to close it and the anemometer and wind direction vane were hanging out.  To my amazement I used the least amount of power to get to her home that I have ever used in the past two years of taking that route.  Both going there and coming home, I only used 28% to go the 37 miles.  The only reason that I can think of for this improvement is the installation of the top box.  While not a major improvement, it is an improvement and it is sure a lot easier to install an off-the-shelf top box than designing, fabricating and installing a dustbin fairing.   

[sendler]

Maybe you can try it with/ without the top box a couple more times to make sure what the difference is. Can you look at Wh consumed for the trip instead of battery percentage? And make sure everything else is the same such as having the battery warm off the charger each time right before leaving.

[WoadRaider]

The ZEV LRC is a much more efficient bike, although it's peak efficiency is closer to 55mph than 75mph.
http://zelectricvehicle.com/22.html

[sendler]

The ZEV LRC is a much more efficient bike

Are they still in buisiness?

[BrianTRice@gmail.com]

The ZEV LRC is a much more efficient bike

Are they still in buisiness?

Off-topic; let's not derail this thread further.

[Killroy]

How much is energy consumption do to motor inefficiency at high speed and not aerodynamic drag.  Gearing could help that. 

[BrianTRice@gmail.com]

How much is energy consumption do to motor inefficiency at high speed and not aerodynamic drag.  Gearing could help that. 

Almost none; I think the powertrain efficiency is measured about 90%, been discussed elsewhere. Power measurements at speed easily show that aerodynamic changes drastically affect efficiency.

Is the contest on for derailment? It'd be nice to start a new thread instead.

[sendler]

How much is energy consumption do to motor inefficiency at high speed and not aerodynamic drag.  Gearing could help that. 

Almost none; I think the powertrain efficiency is measured about 90%

Electrical efficiency begins to fall away after 3,500 rpm as greater amounts of field weakening are used to extend the rpm range of the motor at the given battery voltage. It will be about 10% less at 5,000 rpm and 20% less at top speed.

[togo]

sendler- that's a nice chart.

I notice the name KAMM at the bottom- is it from the same Kamm who created the Kamm back?  His point might have been that shortening a teardrop does more harm than good, and that you are better of with sharp corners instead.  I.e. the Kamm Back seen on any fuel efficient car today.  Obviously on a car you are pushing air up and over since you are wide, and on a motorcycle the Kamm tail would go more in the side to side direction.  Vetter found that a full tail was good but that truncating the tail off square was also pretty good.

What's the source of that diagram?

[Killroy]

This shows clearly that when streamlinig a truncated shape that half the improvements can be lost at the back.
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That is hard to read, can we get a better resolution or re-create it clearly?

[gasdive]

Good luck gasdive!  I look forward to hearing what you decide!  Doing 800 km on an electric motorcycle in 24 hours is huge, and very rewarding! I can't wait to one day soon have you post that you did it!  And then of course everyone will ask you how...

Hi Terry,

I don't often get on here and didn't realise that you'd left such a detailed reply!

As it turns out I've been thinking along the same lines of more charging and modest drag reductions.

I've taken off the crash bars (it's actually a DSP so it had crash bars and siren mounts). I've cabletied an old Hyosung windshield to the handlebars because I had one and cableties are close to the limits of my mechanical skills and I've switched from big textile jacket and pants to an old leather race suit from the back of the wardrobe (which looks silly and must have shrunk a lot around the waist in the last 20 years).

I didn't check the drag for each change as they all seemed a bit to small to see but taken all together I seem to be able to ride about 10-15% faster for the same Wh/km.

I've also got one elcon (as per your previous advice) and I've just got a second one which I haven't yet used, as I still lack a Y connector. I'm trying to figure out how to mount them behind me so they don't increase my frontal area and they sit on the pillion seat which should be strong enough.

High power charging seems possible. There's a Caravan park at the 140 km mark where I can plug into 3 separate 15A 240V circuits. Another 130 km on there's a J1772 next to a 10A 240V and I've just got one of Rush's adaptors for that. Two elcons in the J1772 and the onboard in the 10A 240V. Then it's another 130 km to my Daughters, were I can plug in at the local shopping centre for a slow charge at 10A 240V (one elcon).

My first attempt at getting down there with one elcon took 13 hours! I couldn't use the J1772 so I stopped early at a private plug on Plugshare, then rode to a hotel, booked in and charged for an hour at 2.5 kW. Then because I was late for dinner I didn't end up plugging in until *after* dinner. So 3 hours in a car park in the middle of the night to get me back to the hotel at 1am. Big day and still not home.

So it's exciting times. The Y connector is the only missing bit of the puzzle (oh and how to not pass out from heatstroke in the leathers...). 

So that's where I'm at right now. I'll let you know how I get on when I finally source a Y connector.

Cheers Jason =:)

[grindz145]

I had some fun with photoshop and the Airtech DBL-1 fairing.

For 600 bucks if you can get close to 40% improvement at 60mph, It would be worth it IMO. That would earn you approximately the equivalent of $3k in additional battery pack, if not quite a bit more, even without tail section improvements.

What do you guys think about aesthetics? I honestly think it looks boss.

[BrianTRice@gmail.com]

I had some fun with photoshop and the Airtech DBL-1 fairing.

For 600 bucks if you can get close to 40% improvement at 60mph, It would be worth it IMO. That would earn you approximately the equivalent of $3k in additional battery pack, if not quite a bit more, even without tail section improvements.

What do you guys think about aesthetics? I honestly think it looks boss.

Nice! I was trying to figure out the dimensions to make sure a graphical overlay was to scale. Did you work out the scaling?

I'm kind of preferring the DBL2 so that the existing lights can stay in place and no trimming is required near the footrests.

[grindz145]

Yeah I thought the same thing about the DBL-2 except that it has unnecessary air-scoops, and it's a little smaller (plus I like the the way the DBL-1 looks)

I tried to size it up the best that I could given the cursory dimensions listed on the website, and using the wheels for scale. It's not perfect by any means, but it's roughly the right size.

It would be really nice to be able to remove it easily for non-touring situations.