Dear Mr. Stotland,

 

I'm interested in modifying my '85 K100RT as you describe in the IBMWR article (http://www.ibmwr.org/ktech/k100-heat.html ).

 

The overall process looks straightforward. However, the frame-fairing mods aren't clear to me. Here's what I'm referring to:

 

"My main goal was to get the heat flow escaping from between the fairing and the engine under control. This seemed to be the biggest culprit in making my life miserable. With the tank back in place, by applying cut pieces of foam in judicious locations, I was able to accomplish this about 99.99%. The right side was the worst. It took several pieces, a couple around the air pick up tube and between the frame rail and tank, and a couple applied w/double-sided foam tape to the right fairing half itself. Also jammed a couple between the tank and the frame rails. I found that the correct approach was to try to guide as much of the airflow as possible through the vents on each side, and not let it out between the fairing and the engine."

 

 

Any photos and/or further clarification would be most appreciated, as I start preparing for my 5th Atlanta summer...

 

Thanks again, and good riding!

 

Sincerely,

 

Jim

 

 

 

Jim,


Here’s a little more detail.  Each fairing side has two vent openings to exhaust the radiator blow-by.  Each opening has a small fin that extends inward a short distance.  You can reach through from the outside and feel the gap on the rear-most vent that extends between the end of the fin and the side of the engine/frame.  This opening to the rear of the fairing allows hot air to move to the rear and “escape” below the pads on either side, exposing the rider to that burning sensation.  Take a look here;

 

  

 

 

This shows the inside of the right fairing with one of the already-split-with-closure-tape pieces stuck on the inner edge of the vent lip.  It’s unfortunately hard to see that the foam piece has been cut in a “C”.  The pieces lying on the floor are jammed in to the crevasse that exists between the fairing and the frame.  The left side has a completely different air path, so that took a slightly different design.

 

I even went after the little stuff, like the opening above the intake/filter chamber.  Here’s a shot of the left side;

 

 

 

 

And one of the right side.  Here I’m sealing the gap behind the air intake elbow.  This is one of the two pieces that were lying on the floor.  The second piece is above my hand, and is jammed up in the gap also.  It follows the contours of the fairing and you “guide” it into place as you install the fairing.

 

 

 

 

The goal is to plug up everything “south” of the rearmost vent, so that ALL of the airflow is deflected THROUGH the vent, and not around the INSIDE of the fairing.  BMW uses a rubber seal, much like the seal on a VW between the motor and engine compartment, which reduces but doesn’t eliminate the unwanted airflow.  It took me two tries to “get it right”, and things get rearranged somewhat each time I remove the cover (fortunately few and far-between), but once you attend to every “miss-sealed point, things get a LOT cooler.

 

The key here is to look closely at the point-of-(no) contact between the vent openings on the fairing and the engine/frame, and try to visualize the gaps, then plug them.  Since the foam was so cheap, 

 

I mentioned the fuel-vent hose mod.  Here’s of shot of that inside and out

 

 

 

 

 

This helped tremendously in cooling the gas tank.  At least for awhile… That’s how I really noticed.  Where before, the tank would always heat up in minutes, since the mods were all done, it now stays cool until I pull 6K RPMs for a while.

 

Hope you got the embedded pictures OK.  If not, let me know and I’ll send this back as a word.doc w/separate JPG files.