Help me aeromod my Vectrix

[bennelson]

Hi everyone.

I have a Vectrix electric motorcycle. I've been able to go as far as 91 miles on a single charge so far, but I want MORE. (It's a 9KWH battery pack made from 18 Nissan LEAF batteries.)
(The other cycle in the photo is a friend's, which we ALSO set up with LEAF batteries.)

The bike pulls substantially more current at top speed (about 64 mph, electronically governed,) than it does at 35-45 mph.

Obviously, motorcycles are NOT aerodynamic, and have nots of room for improvement. Motorcycle riders are even less aerodynamic. I'm 6 foot tall and nearly 200 pounds.

Here's a view of me on the motorcycle.



As a "mega-scooter", it has a very comfortable seat, and a very upright riding position. This is great for a view of the road, and looking right over a lot of cars, but not great for aero.

In this photo, the back body of cycle was removed, as is the trunk cover/passenger seat. I was looking at how everything on the back attaches. I noticed that the entire body is aluminum, but the back area, (pretty much everything in black) is steel tubing around the trunk. That whole thing is mounted to the rest of the cycle with only 4 bolts - two on either side. You can see them clearly in the photo.

So, there is very little stopping me from taking the entire back off, and replacing it with some sort of custom aerodynamic tail.

Here's a few images from the aerodynamics tool here on Ecomodder, and of course, it doesn't fit to the cycle well at all - I'm way too tall!




Way back when, I was reading about what Craig Vetter was doing with his Helix, and I always thought those were pretty cool. When I took my motorcycle class, another student there had a Reflex, which I really liked too. Now that I got this Vectrix, I see some similarities (although the seat on the Helix always looked SO LOW!)

More recently, I was looking at some of the work done on Terry Hershner's modified Zero.

I think that a bulkhead right behind me streamlining back to a fishtail, combined with a nosecone that would enclose the front tire would be very slick.

I was also thinking about doing something like adding a pair of Elcon PFC2500 chargers. Those can run on 120v OR 240V and can do 15 amps at 240V, so the pair of them would be 30A/240V which maxes of most public J1772 charging stations. It would also mean that I would have a recharge time of about an hour and 15 minutes. Higher current charging AND aerodynamics could make this into a real road-trip vehicle!

I have very little experience with fiberglass. I'm good at cutting and drilling aluminum, and flattening and welding conduit. I've worked with coroplast a fair amount. My dad built a cedar-strip canoe, which is amazingly light and beautiful. Building a fairing in the same style would be gorgeous, but probably beyond my skill/experience level.

I don't have a budget for buying a Vetter Fairing, although it is possible that I might do some fund-raising as part of a documentary. In which case, I MAY have money for a Vetter fairing.

I'm also hoping to make it out to Ohio in July to check out the Vetter Challenge there, and look at some streamlined cycles.

Motorcycles have different aerodynamic challenges than cans. The biggest being that they are taller, don't have doors, they tilt as they turn, and you need to stick your feet on the ground while stopped.

One big thing that I noticed on Terry Hershner's cycle is that when they re-modified the back end of his cycle, they really lowered the seat. On the Vectrix, the seat is right over the battery box. The cover of the battery box is sort of a stair-step shape, higher in the back than the front. This originally had fans in it for an air-cooling system for the NiMH batteries. Since I upgraded to the Nissan LEAF cells, I removed those fans. I may be able to cut the lid, but something custom, and lower the seat a few inches, but the motor controller is also in that area, and not easily movable.

So, let me know your thoughts! What's the best way to make this thing more aerodynamic?

[spacemanspif]

Fair the front wheel, extend the fairing as far back as you can to comfortably enter/exit the bike and make a boat tail/backrest for you. Extending the windshield would increase fronatl area but at that rake it may not be that big of a deal, dropping the seat would keep frontal area the same and get you out of the air flow. Keeping tucked behind the windshield would do the same but not be as comfortable for you to ride long distances. Im no motorbike expert but I think that those are the pieces to drop aero drag on a bike. Unless you want to make doors and leave the bottom open for your feet.

[cRiPpLe_rOoStEr]

If you could get the seat lowered, or even a recumbent riding position, that would make it way easier. Would you feel confident to do some frame mods?

[bennelson]

I don't want to mod the frame on this. The bulk of the frame is just an aluminum box that holds the batteries, anyways.

However, I did think that a good place to start was just to take the seat off. Depending on how you measure it, the seat is over four inches thick.

I took the seat off and just sat on the battery box. It sort of turns into a recumbent just by doing that. I set up my camera on a tripod and a timer and scaled that photo to the same as a previous one I took, so I could see how tall I was in the standard position versus with the seat removed.

As I was playing with these images, I just started sketching what might be a fairing over the top of it. By the time I was done, I ended up making an animation.

Hope it loads right!

1. Cycle with regular upright sitting position. (Trunk was removed in this photo, shows attachment points for a custom tail.)
2. Seat removed (becomes sort of a recumbent position. Trunk is back in place in this photo.)
3. Imaginary nose-cone added.
4. Imaginary tail added.



Removing the seat sure feels like it drops me a lot. It seems to put my shoulders solidly BELOW the top of the windshield, but my line of sight is still over the top of the windshield. I rode around the block like this. It's real easy for me to tuck all the way behind the windshield, and air pushing on my shoulders seemed like a lot less. (Even though I was just doing a little low speed through my neighborhood. Maybe tomorrow, I can put some foam under my butt and try something a little faster.)

Down that low, the handlebars are just a little far away. I'm not sure if I can adjust them or not. Adding a piece of plywood/foam/cover over the battery box would raise me up a tad, maybe just enough to make reaching the handlebars better.

[Grant-53]

I'd say you are on the right track. Sheet material can work instead of fiberglass and a mixing bowl could make a nose piece. Side panels are a bit tricky but I am going to try hinge mine at an angle along the windscreen. The cross section would be pear shaped and larger at the top.

A different handle bar may be needed. Vetter heated and bent his to fit.

[botsapper]

Something totally out of the box; frontal area reduced, lowered center of gravity, and extra passenger accommodation. Just add a boattail.

https://www.youtube.com/watch?v=h8Xe1iSu6i0

[bennelson]

I gave the scooter a test ride.

I went out on a certain section of road, went to top speed (104 kph) and then held it for a stretch down to a certain landmark (a road I could turn around at.)

I noted the current draw as I rode. It was between 60 an 70 amps northbound and between 70-80 amps southbound. (Guess it wasn't as flat as it looked!)

I then took the seat off, put my bedroom pillow there in its place, sat on the pillow with my feet in a more forward sort of recumbent position, and repeated the same route.

It's hard to tell exactly, as the ammeter dust jump around a bit, and it was gusty winds today too.

The north-bound trip with the lowered seat didn't seem like it was much of a difference in current, although I could certainly feel less wind on my chest than in the standard seating position.

On the south-bound trip with the low seat position, current draw was closer to the 60-70 amps range.

It's hard to say for sure, as I don't have a real-time log, and wind always makes things more challenging, but it appears that the lower seating position has the potential to drop 80A use down to 70A use. That's about 15%

I'd take 15% extra range!

[aerohead]

Originally Posted by botsapper

Something totally out of the box; frontal area reduced, lowered center of gravity, and extra passenger accommodation. Just add a boattail.

[aerohead]

Originally Posted by bennelson

I gave the scooter a test ride.

I went out on a certain section of road, went to top speed (104 kph) and then held it for a stretch down to a certain landmark (a road I could turn around at.)

I noted the current draw as I rode. It was between 60 an 70 amps northbound and between 70-80 amps southbound. (Guess it wasn't as flat as it looked!)

I then took the seat off, put my bedroom pillow there in its place, sat on the pillow with my feet in a more forward sort of recumbent position, and repeated the same route.

It's hard to tell exactly, as the ammeter dust jump around a bit, and it was gusty winds today too.

The north-bound trip with the lowered seat didn't seem like it was much of a difference in current, although I could certainly feel less wind on my chest than in the standard seating position.

On the south-bound trip with the low seat position, current draw was closer to the 60-70 amps range.

It's hard to say for sure, as I don't have a real-time log, and wind always makes things more challenging, but it appears that the lower seating position has the potential to drop 80A use down to 70A use. That's about 15%

I'd take 15% extra range!

Maybe you're experiencing same Cd, only with reduced frontal .

[drees]

Ben, I presume you've seen Electric Terry's Zero and his Vetter fairings? Just Google it if not, you'll find tons of pictures.