The Body panels on the bike

Since a good portion of the frame has been cut away to make room for the engine, those parts will all have to be replaced or new parts fabricated to bring the structural stability back into the bike. There is also a big consideration for safety, such as the addition of scatter shields should there be a turbine or compressor wheel failure.

Scatter shields

The scatter shields will play a big role in the structure of the bike. There is simply no need to use smaller material to connect the frame pieces and then lay a shield over it. The 1/4 inch steel plate that is being used directly over the turbine and compressor should be more than adequate to strengthen the frame, and provide a little protection from flying debris in the event that something goes awry. While I don't plan on any accidents, it doesn't hurt to be safe when you are sitting directly over hot metal rotating at high velocity!

Air flow

I decided to make the shields also act as an air tunnel to help in cooling the oil and pumps which will be mounted under the tank. The tank has a large void underneath in which the original air breather for the bike was situated. The air will flow in through the front of the bike and pass through the oil cooler. It will then pass under the tank, over the pumps, and out from the sides as depicted by the blue arrows in the photo above.

Oil Cooler

The oil cooler will be using a "pull" type fan behind it, which will pull the cooling air through the plates. The fan is going to be a large muffin type fan, similar in design to the ones used on computer power supplies.

Air diverter

So that the fan will operate at maximum efficiency, air diverters were fabricated to fit behind the oil cooler. They will act as a sort of shroud to make sure that the air can only be puled in through the cooler, and not take an alternate route.

Air shroud

The idea is to keep the air flowing through the system as fluidly as possible. The more air we can keep flowing over the cooler, the better it will perform. To fill in the spaces around the oil cooler, a flexible rubber foam gasket will be used, which is capable of standing up to the high temperatures which can reach up to 400 degrees F for short times.

Air path

The photo above gives a good view of the configuration of the scatter shields, and oil cooler air flow. The fan will mount in the opening right behind the oil cooler, and will lay in a horizontal position so that air is drawn up through it into the higher area under the tank. A special cooling system will also be mounted here to further increase efficiency of the whole system. Further shielding and supports will be added to the frame once the exhaust has been fitted to the bike. A special note here, the shock mount will be getting removed completely and the bike will become a rigid tail. Although it is possible to route the exhaust gasses past the shock, the tighter bends required in the exhaust tubing would lead to losses in the system. Having a straight through passage for the exhaust will keep things cleaner, and also provide more room for the plumbing and additional components. Struts will be fabricated soon to extend from the upper frame down to the swingarm.

Engine mounted in bike

With enough work done on the engine to mount it in the bike, we needed to see if everything would fit. The combustion chamber was bolted to our old turbo which is in the bike for mock up purposes.

Engine angled up

One of the problems with mounting the combustion chamber in the new position has been ground clearance. There is plenty of clearance beneath the bike, but as a right turn is made and the bike leans it could cause the combustor to drag. To give more ground clearance, the combustor will have to be angled up slightly on the outside edge.

Engine in the bike

With the engine in a perfectly horizontal position, there would be enough clearance for a 45 degree lean in a right hand corner. While this might seem to be more than enough, it does not take into account the bike sitting lower when the front forks are at the bottom of their compression range. By slightly raising the outside edge, enough ground clearance can be made up to eliminate the problem.

Too much angle

As the engine is raised on the outside, the turbine section of the turbo rotates along with it. The combustion chamber could be made to stand straight up and down on the side of the bike if needed. Since the turbine flange is offset to the center of rotation, the further up you lift the outside of the combustor, the further is sticks out the right side of the bike.

Up too far

With some adjustments, it was determined that the combustor would sit almost horizontal under the bike. The outside edge would have just a slight lift to it making it about 1/2 inch higher than the inside. This would give the additional ground clearance to keep the 45 degree lean ability of the bike even with the forks fully compressed. The picture above shows the combustor still angled up about 2 inches.

Sticks out too far!

Again, the photo above shows the combustor angled too steeply. The lift is about 2 inches on the outside and would provide ground clearance, but at the same time the engine sticks out further. Now that the minute angle has been settled on, brackets will be welded in place to hold the combustor the the frame once the entire engine is completed and mounted to the new turbo.

Body panels on the bike

We really needed to test fit the body panels on the bike to see how the fit would be in relation to all the new components. With the body panels on, the bike starts to look more like its big brothers.

Fairing on right side

Looking closely at the picture above, you can see the exhaust manifold for the engine still mounted in place at the bottom of the bike. The fairings will have to be cut away to make room for the engine on the right hand side. The cutouts will follow the shape of the engine, and will leave as much of the original body as possible.

Front of the bike

From the front, the bike sure does look different from other YSR's! I am positive that this is the first time that one of these bikes has ever had a jet engine cradled inside of its frame. The leaf blower for starting will have to go straight in through the front forks. I may fabricate an air inlet duct to get the inlet air over the front tire more efficiently, and also to help keep out debris.

The drivers view

From the drivers seat the bike starts to feel a bit more flushed out. The body panels are wider than the frame, and stick out of both sides by about 3.5 inches. The additional clearance inside of the fairings will give lots more room for things like batteries and pumps. We will be using every bit of that room I assure you!

Front fairings

The area in the front fairing also provides a handy place to put things such as the engine ECU. The original mounts on the front fairing brace for the speedo and dash panel will be cut away to make room for the ECU, and possibly an additional battery pack or two.

Turbo to body clearance

A slight part of the body will also have to be removed to allow clearance for the outlet of the turbo compressor. Once again, we will only remove enough material to make room for the parts so that the bike will retain a stock appearance. Well, if that is possible with a big combustion chamber sticking out the side and an afterburner sticking out the back!

Room for the oil tank

Without the original combustion chamber sitting under the compressor, there is plenty of room to have the oil tank mounted right up front. This will also keep the cool parts (the compressor and tank) up front in the airstream, and away from the hot parts (the turbine and exhaust).

Hot air exhaust under tank

The air that flows through the oil cooler and under the tank will eventually exit right here from the sides of the tank. It is a nice convenient place to get the hot air out, but will make things a bit warm against the legs of the rider! Hopefully the temperature won't be too bad.

Under the seat

With the rear shock strut removed completely, there will be a lot more room under the frame to route the exhaust. Additional bracing will be required under here once the final exhaust path is chosen.

Place for a battery?

This side view of the front fairing area seen above, shows that there is some room in there for a battery or other goodies. Somehow, we will make use of this space!

Rear of the bike

Finally, bringing up the rear is, well, the rear of the bike. Trust me when I say that this seat was not made for a 6 foot tall person! You can fit, but it is a tight fit to be sure. There may be some room under the rear seat area originally used as the battery compartment. The only way to know for sure is to check the temperatures under there with the engine mounted and running through the afterburner. I just don't know how hot it will get yet. Once we know, it will either be sealed off, or used for batteries or other components.

Well, that's it for this time around. Plenty more updates to come as well as the test firing of the new engine! Thanks to all of our supporters, and remember to keep helping out to support the site so we can bring you more great builds. Visiting our advertisers whose products interest you is a great way to help us. Look for the ads on our pages and be sure to read this if you need more info on how our advertisements work for us. See you soon!

Russ W. Moore
Bad Brothers Racing

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