Tuesday, August 25, 2015

Sportster Forty Eight EFI to Carb Conversion

I had some trouble with the forty eight a year and a half ago, ended up having to rewire the bike to stock on the side of the road after my fuel computer failed.  I decided to swap to a carb.  I got an s&s intake manifold and mounted a Mikuni VM38 carb.  I had a throttle cable and throttle grip in the garage already and used those.  

For the Ignition I reached out to Altman Micro Machines in Germany.  They make an electronic ignition module that uses your crank angle sensor and the wires from the coil to run the ignition.  There are settings for advance base setting, advance rise curve, and rev limit.  There are literally 6 wires that you need to keep from the main harness.  Then there are a ground and ignition + and you are ready to start the bike.  I ended up just gutting the harness and starting from scratch.  But the amount of wires removed was awesome.  

I had a tank with a ridge in the center that was being swapped onto various bikes.  I welded on some bungs to mount the tank, now i just need to lower the rear mount a bit so that it flows a little better... 

I still need to make an ignition coil mount, and make a battery tray, but other than those two it should be ready to ride.... I will be swapping out the stock oil tank for something else soon, and there is a seat in mind..... Still have to figure that out...