Building and adding the Streamlined Tail Kit to the Body
Alan has been driving his Ninja 250 around with the Body Kit in place, but no Tail Kit.
"I filled up the Ninja 250 this afternoon. I was running errands so I filled it up. Hey the rear body really comes in handy to haul stuff! Of course you already knew that. Gas mileage, 88.617 MPG. That included the ride down to your house with no tail. So that gas tank is inconclusive. Actually we might not see the real improvement until the tail is installed. I finally check the aluminum panels around the mufflers right after I got off the freeway. It was at air temperature. Not even warm."
|So much for the "Kamm" effect...|
"I noticed that the white foam pressed into place at the rear of the body gets pushed forward when I am riding on the freeway. I guess the Kamm Effect has some drawbacks."
Craig comments: Back in the 30s, Wunibald Kamm said that you could cut off the long tail without adding too much drag.
Why would I want to add any drag?
Look at the above picture. It is essentually a "Kamm" cut. Air curling around from the sides - caused by incomplete streamlining - has turned 180 degrees to push the foam forward out of place.
Obviously, this is power-robbing drag.
Alan continued: "Riding in heavy rush hour traffic at 60-70 MPH I get a some buffeting. This could be from the enclosed front wheel. I have not ridden the Ninja 250 with the new rear body enough to fill the gas tank yet. With my observations the body might not show improvement until the tail is installed."
Craig continues: Alan's observations are very important. He knows his bike!
Visiting our Milk Carton Paper supplier
|Back in April, the folks at Salinas Wax Paper supplied me with the Milk Carton Paper to skin my streamliner. It has been for six months and I wanted to show them the results of thousands of miles of real use. As you can see, everybody was interested in seeing how it held up. |
Obviously, it is holding up quite well. 36" wide paper would reduce the number of seams. They believe they can find what we need. Better yet, they think they told me about a special version of Milk Carton Paper that could be even more attractive. We'll see!
Some of you have said that you are having trouble finding this paper. We can make it available to you in the kit.
Installing the streamliner skin with Banana Tacks
Our first Kit of Banana Tacks
These can be painted. The Streamlined body on Alan's Ninja took 86 Banana Tacks. The Tail took 36 more.
Punch a hole in Milk Carton Paper
We pre-drilled the aluminum with 1/4" holes and shined a light from the inside to see where to punch
Enlarge it with a taper
Press Banana Tack in. Done.
To remove them, press them out from the inside
It is time to finish the Tail Kit for the Ninja 250
|Alan adds the stringers to generate the tail.||I figure out how to add in a LED Tail Light|
|Al;an has been riding with the Streamlined Body Kit only. It is time to finish it with the Tail Kit. Up until now, I just assumed that we would be making the Tail as a separate piece, held on with bungee cords, as on my Streamlined Helix. Alan and I discussed the fact that I actually never remove the tail. It was going to take a lot of time to solve a problem that is not a problem. We decided to make the Body and Tail one piece and save some time. |
In a few minutes, Alan had pushed out the Banana Tacks and removed the skin.
To continue the aluminum bottom, I decided to use the much lighter printing plates from the local newspaper:
Streamlining with recycled aluminum printing plates
These thin sheets of aluminum, .006" thick, can be cut with scissors. The holes can punched the same as the Milk Carton Paper. Best of all, these sheets of aluminum are usually free. Put the printed side in, shiny side out.
|When the thin recycled printer sheet stock curved, it becomes enormously strong.||We decided it was time to weigh the combined Body and Tail.|
33 pounds of Streamlined Body and Tail
|Alan figures that the two, 10 pound C-clamps make it seem to weigh 33 pounds. |
Actually, it looks like the thickness of the aluminum can be reduced almost everywhere without any loss in strength. This can take significant weight out.
We decided to weigh the original Ninja parts Alan removed along the way:
17 pounds of removed Ninja pieces
We figure the Streamlined rear Bodywork, when completed, will add around 20 pounds to the weight of the stock Ninja.
Net gain: 15 pounds, so far
"Bag - O - Ninja Parts"
Do you remember this man from Chapter 10?
It was my friend, Don Ask who ran for County Supervisor. After the election was over, he gave me all his Coroplast signs.
We need a rear bulkhead to keep things from falling too far back. Coroplast is flat, lightweight, durable and best of all: free.
Elections are coming up. Recycle those old Coroplast political signs.
|The first Vetter Streamliner Kit is light, strong, holds four bags of groceries and can be made with simple tools. The whole thing goes on or off with (3) bolts. |
One reader asked how we get access to the rear storage: "Good question. The Ninja 250 is very small and the rear storage sump is not that far back. Before we settled upon this design, we made sure it was easy to get to. We can easily reach all the way into every corner.
I would not make a mistake like that.
We put the storage sump in to guarantee the carrying of 4 bags of groceries. Of course, we do not always carry 4 bags of groceries, but, it is nice to have the storage space. If it was mine, I would throw lightweight stuff in there I did not have to get to very often: a bottle of oil... a qt of extra gas... rags, cold weather stuff, etc. I think I would cover it with a little sheet of aluminum trap door lid. I'd keep heavy tools stowed more forward to keep the Center of Gravity forward. It will be interesting to see how Alan uses his space.
Glad you are paying attention."
Time to fit new milk carton paper and complete the streamlining.
With the new streamlined skin in place and the seat is lowered an inch, Alan is ready to put some miles on his Streamlined Ninja.
To the right, is the way Alan put 10,000 miles on his bike over the summer of 2011. I want to know if the new streamlining feels any different.
|Thursday, Nov 3, Alan reports:|
|"The ride home today was uneventful, that is a good thing. I took the coastal route by Monterey to get home and the cross winds did not affect the completed tail on my Ninja 250. The Ninja 250 also passed the semi-truck test.Oddly riding north on highway 101 the Ninja 250 bouncing around on the freeway. The only cause seemed to come from gusting head winds.The thinner seat worked fine. After a couple of hours with the new seat my butt was getting a little sore. The fuel economy riding home was only a few miles-per-gallon above what I usually get. So more testing will be needed to verify if there is any improvement with the new tail." |
You outta see this thing in the dark! The LED lights in the tail are spectacular.
|Nov 11, 2011: Alan reports in: Since I installed the new tail I have been on vacation with my wife. I will not get to really test the new tail until I ride it to Las Vegas. |
|Some correspondence worth publishing:|
|Craig: Thanks for your tireless work and efforts!!!!!!!!!!!!!!!!!!!!!! I was in the IHPVA in the 1980s............ and believe in the cause of energy efficiency, security........... |
I am interested in your high mileage fairing kits for using with a low horse power motorcycle, hopefully recumbent. I am worried about noise from the motor in side the fairing, cooling the motor. Can you suggest anything.....? Electric motor cycle? Would like to cruise at 55mph at least and be street legal.
Thank you in advance. Craig M.
|I have made three streamliners. Lets point out pros and cons so you can decide:|
|Designed for 70 mph, into a 30 mph headwind, sitting up and comfortable |
Designed to carry 4 bags of groceries
Designed to be a bike you would really want to ride
Began the Vetter Fuel Challenges
109 mpg so far
Available in kit form
Designed to be inexpensive to build
Designed to be lightweight, and made from locally available materials
Designed to be inexpensively shipped by UPS
Designed to fit any bike.
Streamlining on Helix is limited only by tiny wheels
Way too useful to end up in a museum.
|Designed for "Luxury Touring" at 55 mph |
250 cc Kaw single
Began the Vetter Fuel Economy Contests
No intention to duplicate
Labor intensive to make
Hard to get on and off
Never was "first choice" to ride
Ended up in AMA Hall of Fame Museum
|Designed for 55 mph |
Production version of Charly Perethian's Rifle design of 1982
Designed to win contests
Designed to be duplicated. About 25 made
Won all the contests with 125-180 cc engines.
Maxed out at 477 mpg!
Originally made of ABS. Currently in fi-glass
Tooling still here; streamlined body is still available
Expensive to ship
Hard to get in and out off
Never was "first choice" to ride
Ended up in Smithsonian
|In Summary: 10-12 horsepower (125-180 cc air cooled engines) is adequate for 55 mph, sitting up and comfortable. |
At 70 mph, into headwinds and hills, you need more power. Probably 16-20 hp. (250cc) Liquid cooling seems essential.
Read the results of the 2011 Mid Ohio Vetter Challenge to see the state of electrics
|Another reader asks: |
Is there a reason for the very long tail? If the tail was going to be built non removable could this whole assembly be made shorter, say to the body kit length, or would that have a negative effect?
|The answer is very simple. Left: Me on my Helix, 3 years ago. Center: A streamlined shape just big enough to go around me and my Honda Helix. Right: Real streamlining. |
My understanding is that any shape other than this would be less streamlined.
If you make one, Mike, you can cut it off any place you want and see what it does. This is a grand adventure, you know. I am sure we are learning things nobody knows.
Come join the club.
Page posted Oct 27, 2011
Updated Nov 11, 2011