CBR250R Vetter style aero mods

[sendler]

I had initially planned to just make a simple boat tail solo trunk to take the place of the rack on the passenger seat that I am now using to carry a 30 liter duffel bag but have decided that this wouldn't be big enough. I was hesitant to make the commitment of relocating any of the stock locations of my lights but after buying my camping gear I can see that the most roomy and aero way to carry it all will be a Vetter style tail so I am going to build one for my CBR250R. The front half at least, back to include some storage behind the rear wheel like Allen has. Craig has the whole thing dialed in quite well with his latest build but I had a slightly different idea for the construction where the floor of the storage area will be the full width and length and dictate the shape of the plan view of the tail and provide the strength and mounting points. I would make this part out of 3/8 marine ply and attach the front and rear bulkheads to it. A cut out in the back like a pumpkin lid will allow access to the lower storage behind the wheel for light items like my sleeping bag and pad. I am going to stay with the head forward riding position for now as I am very comfortable and enjoy the handling performance riding this way. And I can keep a smaller frontal area. I should need only 18-19 inches of width for the tail to cover my hips and shoulders and a height of only slightly higher than the stock windscreen. Eventually I could see building with some other donor for a low seat/ feet forward design with the real Vetter nose and turret.

[low&slow]

Great minds must think alike! When I visited Craig, I looked more critically at my current tail and it's too small. I need to make it taller and longer with more storage space so that it can hold the mandatory 4 bags of groceries. I might start on it in the next 2 weeks. Keep us posted , your Honda will benefit a lot with a tail in my opinion.
all the best, l&s

[FXSTi]

It sounds like a great plan. Is it possible that 3/8th plywood is a bit of overkill? Quarter inch would carry any load that you would carry on a bike, it's not like you are spanning a great distance.

Have you done any drawings or Photoshops so we can see? This sounds cool.

Kirk

[sendler]

I like the idea of the high ply count and weather survival of the marine ply and 3/8 will take a small screw in from the side. It is only one piece for the back bone of the design so will only add a couple pounds over using all aluminum.

[sendler]

I am having trouble finding the coated paper that Vetter is using for his aero tail/ trunk so I am considering some alternatives. I could use .020" aluminum at $3/ square foot but it will be prone to dent. I wonder if Coroplast would work well or if the open core would be a problem with water in freezing temps. I see they also make signs out of Lexan which I can get in .020 which is supposedly possible to be cut with scissors and should be flexible enough. Will it crack around screw holes?

[bschloop]

Are you going to be at the Ohio challenge? with a head forward design, you might want to look at putting two bags either side of the rear wheel, and two behind. this would reduce the height of your tail. that is how I have decided to go. it would likely make for a smaller frontal area, and less susceptibility to side wind.

[sendler]

I hope to get to Ohio but can't say for sure If I will be able to get away. 430 miles from my house is easily rideable in a day. The more I read and think about what Craig is doing with this, the more it seems like the ground floor of a revolution. It would be an honor to be pictured with these guys.
"Bags" on the side of the rear wheel is relative. There is some (wasted?) room on the sides of a tail that could be use for thin items like books and maps but might be more trouble than it is worth to skin and waterproof. I should have plenty of room if I use the space behind the rear wheel instead which is free air and beneficial to cd. My overall height will be much lower than Alan's as well as I plan to only come up as high as my shoulders when tucked and only need 19" wide to cover my hips. I expect to add nearly zero frontal area and make a slight improvement in cd while adding 80 liters of lockable storage. Actual side bags will add frontal area and increase cd but the more important thing is to do whatever it takes to have enough luggage room to ride when and where you may want to instead of taking the car. The first step is to just get more small bikes on the road to increase acceptance. And then to stream line them. I would hope that everyone with any kind of fuel efficient motorcycle, groceries or not, who has their heart in the right place would be welcome to show up to ride along and contribute comparative data for the event. It would really serve to drive home the advantages of stream lining to have some stock Ninjas ride along to show their stock 65mpg next to Allen's 100. Maybe then someday Honda would take note and make something ready made for us that looks like Craig's drawing.

[low&slow]

Sendler, I just finished skinning my new tail section today and I used coroplast panels on the sides and plasticized sign papers for the rounded top. The coroplast is very easy to work with and pretty rigid in line with the tubes. I built my framework with 3/8" and 1/4" plywood bulkheads, light wood and sheetrock edging stringers. The coroplast is very light and provides additional stiffness to tailsection. The more I use coroplast the better I like it. I'm not sure about the lexan but I think it's too brittle to be a good siding material.

[low&slow]

Sendler, I just finished skinning my new tail section today and I used coroplast panels on the sides and plasticized sign paper for the rounded top. The coroplast is very easy to work with and pretty rigid in line with the tubes. I built my framework with 3/8" and 1/4" plywood bulkheads, light wood and sheetrock edging stringers. The coroplast is very light and provides additional stiffness to the tailsection. The more I use coroplast the better I like it. Plus if you are an election sign harvester like me its free!

I'm not sure about the lexan but I think it's too brittle to be a good siding material.

[sendler]

Originally Posted by low&slow

Sendler, I just finished skinning my new tail section today and I used coroplast panels on the sides and plasticized sign paper for the rounded top.

You didn't want to use the coroplast for the top too? Post some pics over on your thread when you get a chance. I'm interested in the stringers too. I was going to use 1/16 aluminum angle with one leg sunk straight into plywood bulkheads but the sheetrock corners could be cut with scissors and tacked on with no slotting and routing of the wood. And is way cheaper. Sounds great!