Not Yet Named Reverse Trike

[HydroJim]

This is a build log documenting my design and eventually construction of a reverse trike. Construction is slated to begin in summer 2013 and I want to be done with the trike by October so I can enjoy it before the weather gets bad. This is going to be a basic build so I'm not going to have windshield wipers, defrosters, etc. Therefore, it can only be driven on nice days. Later down the road, I'd like to convert it to electric, but right now that is out of my budget.

Here is the model I'm currently working on:


I'm still trying to figure out how I want to design the front end. I want to avoid jamming a bunch of air between the vehicle body and the wheel pontoons. In it's current square state, it's very easy to build, but I'd imagine it's not as ideal aerodynamically. I want to make it smooth and flowing, but that makes it more complex to build. I guess it depends how much time I Want to spend on it.

Anyway, let me know what you see in my model or things you might change.

[brucepick]

Dang, it looks very smooth aerodynamically to me!

When you say "current square state" are you talking about the transition from the not-yet-detailed nose bubble to the area where windshield meets front side panels? If those areas, and the drawn flat tops of the wheel fairings, are the only non-tapered surfaces on the trike, you will still be way ahead of just about anything on the road, and ahead of many mpg project vehicles also.

I do see what looks like an M. C. Escher style falsehood in the horizontal top edges of the front side panels. At the front, the tops of the side panels are visibly several inches below the top of what I'll call the nose cone arch. Yet at the rear of the side panels, their tops are even with the bottom of the windshield. That is, even with the top of the nosecone arch. Something you'll work out as you fill in the details on this plan.

[pete c]

Looking at that drawing, it looks as if there is not enough leg room with the seat mounted where it is. I think it might be a good idea to more the front wheels a bit further forward and possibly even a bit outboard. This helps in a number of ways. Moving them forward and outboard gets them further way from the turbulence around the nose. Getting them outboard helps with stability

You might want to contact the Edison2 folks and see if they might sell you their front suspension. It is definitely the cleanest way to do it.

[HydroJim]

brucepick- I think you understood what I was talking about. I had a hard time describing it.

the M.C. escher-esque thing you are seeing is just an optical illusion from this angle. the square tube chassis is essentially a box and I was wondering if I should have the top edges of the box follow the contour of the F16 canopy. I believe it shouldn't affect performance much because the air has to be moved out of the way one way or another

The wheel fairings will be tapered, I just didn't feel like drawing it in because it's a lot of time and I already have it visualized well in my head.

pete c- I think you're right about the leg room. A lot of my specs are guesses so I may need to extend the passenger compartment slightly.

My budget for this build is $3000 so I was planning on using ATV parts for the front upright/spindle/hub/rotor/caliper set-up. the a-arms will be custom and I will be using civic VX wheels.

The edison2 suspension would allow me to fully fair the currently exposed suspension area so that would be nice. I guess I'll contact them and see if I could get something on the cheap.

right now my track is at 67 inches, so I'm not sure if I'd want to go much farther out

[sheepdog 44]

Will it be front or rear wheel drive, engine type, displacement? A rear engined vehicle will have better aerodynamics with naca ducts.

Here's some inspiration from my favorite vehicle, the Pulse Autocycle. My idea would be to modify this design aesthetically by moving the outriggers forward to become your outboard two front steering wheels. Getting rid of the front center wheel, and blunting the nose. That body shape over your frame with minor adjustment could follow the streamline template 100% very easily. Naca duct the rear engine, exhaust at the very end. Video side mirrors. Also using two windshield pieces like the Pulse, might be easier than a single canopy piece.

[HydroJim]

sheepdog44- that's about exactly what I had in mind except instead of a fairing around the suspension, I'll be fairing the suspension itself. the Cd won't be as good, but the frontal area will be drastically reduced resulting in a lower overall Cd.

Specs:
Donor: Kawasaki Ninja 250R(really any 250cc will do)
Engine Size: 250cc
Chassis: Mild Steel
Body: fiberglass over foam and WeatherSpotter's Wood Plastic Composite
Weight: Trying to keep the weight under 400 lbs if possible. 500 lb max. anything high and I'll need a bigger engine
Drive: Rear Wheel Drive
Cooling system: NACA ducted cooling system with the hot air being exhausted into the vehicle's small wake
Front suspension: Honda TRX 250X with custom a-arms
Steering: Strange Engineering S3437
Front Wheel/Tire: Honda Civic VX with 155/80R13
Frontal Area: 9-10 square feet
Estimated Cd: .15-.17

I think that's everything I can think of...

[sheepdog 44]

That sounds very doable! Simple, durable, cheap, reliable. I'd expect far north of 120mpg. If you go into the aerodynamic and fuel consumption calculator, you can get a idea of what mpg to expect. Freeway speeds should be no issue.

It would probably meet all the design criteria for Craig Vetter's 100mpg+ freedom machine. Considering the lower ride height and complete fairing.

[gone-ot]

...call it a TRYKE.

[HydroJim]

The spreadsheet is showing 200 mpg at 60 mph, but I'm guessing on a few of the values. I'd expect closer to 150 mpg which isn't too bad

and...it needs a cooler name than TRYKE.

[brucepick]

Call it Aerotrike.

That describes it well and also has a pretty good "ring".