I converted a 1998 Road King EFI from Magnetti Marelli to S&S VFI. It was quite expensive but it was a nice system and user friendly. Replaced every sensor on the bike also. Was it worth it? Hell no. Leave it alone or get a newer bike.

 

The old Magnetti Marelli system was not a terrible system. All the weaknesses have been pointed out already.

Being an older simpler EFI system....you can still fix the system yourself without all the computer stuff. Hot and cold idle are annoying at times....but it’s just a quirk that is tolerated.

What will stop the EFI EVO bike....is the engine temperature sensor. Harley is the only one that has that sensor. I’ve looked and tried to cross reference with no luck whatsoever. When Harley decides to discontinue the sensor.....I’ll be switching to carburetor. Or if I decide to take long trips far away from home....I’ll switch to carburetor for simplicity.

I recommend keeping the system as long as it’s working well and parts are available.

 

Correct answer...

 

I love it when an old thread comes back around.

I've tried to locate that sensor too. I thought maybe Standard motor products made it but couldn't find anything in their catalog. I was told that the MMI may have come from an Italian bike manufacturer but still no luck. The sensor is still available but prices vary wildly. I keep a spare in the shop for when the old one shorts out. When I can't get a replacement is when I'll be doing something else.


Carl

 

ok I have the opportunity to buy a 1 owner 2001 road king classic with 4500 miles on it, has not been riden in many years, had a battery tender hooked up to it so ignition switch illuminated speedo for mileage i did not try to start it as it isn't mine.....yet? any way this is a fuel injected bike, what are the pros and the cons on the bike? and what are the fixes/ expenses involved? can the older systems be converted to carb without alot of problems or? are parts available? any way I might be bale to get it for cheap, I think they stopped riding due to their age ( in their mid 80s now bought it new)not bike problems, any help i would appreciate atomdoug@gmail.com

 

Just so you know you are looking at a Twincam and asking in the EVO forum.
You will probably get better answers if you ask in the touring forum.

 

Since this thread is back around I've got a question, has anyone had any luck pulling an old head temp sensor apart and trying to fix it? I'm curious if it's even possible.

 

I have not pulled an old one apart, however, I have a THEORY that if you have a good one to measure, or maybe the FSM if the spec is in it, you can buy a thermistor from one of the big suppliers and use that. Cost probably under a buck, buy you'll have to buy like $20 worth of them at a time. That's what I would do. I'm using two thermistors like that now on the Sportster, one in the intake (IAT) and one epoxied to a ring terminal under the motor mount bolt (CHT).

 

Thanks, how could you mount one in the EVO head that would be protected from the heat and any moisture from riding in some rain. I have an old temp sensor I could pull apart but was hoping someone else had destroyed one first.

 

The thermistor is just a little component, not unlike a resistor, capacitor or diode. Two leads coming out of a small blob. Epoxy it inside something, solder wires to the leads, mount it how the original was. Water/rain? Big deal. That's what shrinkwrap is for.

If that's a good one, then do this: Get an accurate multimeter and infrared pyrometer. Measure the temp and resistance. Change the temp (oven, freezer, etc.) and record the temp and resistance. Then we can fit the curve to an easily available thermistor and you can use that.