I have a 98 Road King with the Magnetti Marelli fuel injection I'd like to replace with a better fuel injection system. What are my options?

 

Check out Horsepower Inc.... https://www.horsepowerinc.net/throttle-bodies

 

S&S also has a replacement, which is more user friendly I hear.

 

What does better mean to you?
What is the need or want?
The system is serviceable and there are several forum members that are running the M & M.
For example: did someone tell you to change it just because or are you having a problem?
It could be rather wasteful to spend $1000 to $2000 USA dollars when the only problem is a loose crank position sensor connector that can be fixed for FREE.

 

This is a cut and paste that i made a while back that seems to help many folks with that ERA of bike.
Most read it and say whatever..then return to ask how to find the list when they need it.
Consider printing or taking picture of information and keeping in phone so you have information when needed.
Common problems:

1-COMMON...Two fuel hoses under tank leak after 10 years. Harley $$$$$$$ or use Goodridge HDFL005 under $160 USA dollars or LESS total for BOTH if you check google .

The Goodridge lines are less than half the price of the Harley parts and are of good quality.

2-COMMON..speedometer LCD (odometer screen bleed). requires replacement when unable to read miles ridden. Requires cutting about 12 wires. NOT PLUG AND PLAY LIKE NEWER ONES. A retrofit kit is available to make it plug and play but you still need to cut about 12 wires...new reports of a shop that fixes LCD.

3-COMMON..Cam position sensor...very difficult starting, lots of cranking but does not catch. A lot of cranking and no start then you wait a second and a quick tap to start button and it starts with very little cranking…look for visible goo (beige) leak under timer cone (right foot) at black wire exit from botton of cone…You will have plenty of warning…dozens and dozens of difficult starts.

4-CRANK position sensor by oil filter (RARE) but if you use a power commander the signal must be 100%..This is very rare.

5-(MEDIUM COMMON)Tank liner releases at middle section near fuel pump..blocks flow of fuel..loss of power, slow down and piece moves from fuel inlet so bike is OK but then becomes trapped again so cycle repeats.. FREE REPAIR..open gas tank access lid, drain fuel and clean piece out..I would carry the little bit required to remove screw..The book says you need to replace the one time use screws but if you are careful and replace in the same location it will be re-usable at least one time..

6- VERY COMMON...ENGINE TEMPERATURE SENSOR...very common, general rough riding as bike bucks from cold to hot rapidly..$100 part…I have studied this situation and it seems like a cheap resistor with 150 ohm rating could have its leads pushed into the connector plug ends in order to trick the bike into thinking it was warm or just unplug engine idle control when bike is settled but will need to hold throttle for warm-up.
7- Bikes that are pressure washed or in snow conditions with salt roads or people that added a power commander and destroyed the rubber boot at ECM..GROUNDING PIN ON ECM becomes corroded and requires cleaning.
8-The little chrome cover cap thing with the allen bolt on the starter end will get loose one time and you will chase the rattle a long time until you figure out that under the cover is two 0.15 cent nuts and one is lost.
***-The shift linkage ends SUCK on all harleys and you need to change those yesterday to heim joints look on ebay if on a budget for: Heim Joint Rod End 5/16" with bolts for Harley Davidson as they should be about $10-$15 delivered for both.
****VERY IMPORTANT...THE CRANK POSITION SENSOR USES AN INSERT TWIST AND LOCK CONNECTION. MAKE 100% sure it is tight, zip tied and secure and then tie it one more time.. Located at throttle side of frame behind the PAINTED plastic side cover by seat (remove cover) and hidden by the triangle portion of frame..connector is black and about 2 or 3 inches long and the thickness of a fat pencil.
That thing had me scratching my head for a long time trying to chase an intermittant cut-off over bumps. Side of the road frustration thing..Many shops are unable to identify the simple problem while others waste your money by replacing it when it was only loose.
THE PARTS ARE READILY AVAILABLE for this bike with the exception of the gas tank from either the dealer or aftermarket.

I would imagine you have the service book or will get the service book for this bike from Harley 99483-98 . Finally if needed you get the book read chapter 9. You can review check engine codes with no tools by following a simple sequence.

I would review the fuel lines. If you do NOT have the goodridge lines HDFL005 then I would consider carrying some in your saddle bag. Rarely does a dealer stock the Harley ones.

Consider using regular Dyno oil as the synthetics are too good at locating leaks.

Check the allen bolt at the transmission shift lever. The shift lever that attaches to the transmission spline/shaft. People forget to check that allen/hex bolt and then the splines on the lever get chewed.

Shaft is harder than lever so the lever will strip. Major labor to remove the outer primary, inner primary, and clutch hub just to replace the lever on that year of bike just because someone did not inspect that allen/hex bolt.

 

How to read codes:
1-turn ignition key switch to ignition and then turn off 1 second after fuel pump stops.
2.repeat #1 again..remember 1 second after pump stops
3.turn ignition key switch to ignition and wait about 8 seconds for a bunch of flashing of the check engine light
it will then stop for 2 seconds..get ready... these are the codes you must count:
it will slowly flash 1,2,3,5....there is NO 4....this is the first digit of the 2 digit code ..so it can only be 1,2,3,5 __ __
then a 2 second pause...then you will get second digit of the 2 digit code..it can only be 1,2,3,4,5,6
remember after the complete 2 digit code is given you will go back to the rapid flash sequence..
there are a total of 15 codes available with this procedure
examples
52,53,54,55 bad news ECM replacement
56 crank/cam sensor
11 throttle sensor
12 barometric

14 engine temp. sensor

15 intake temp sensor
23 and 32 are injectors front/rear
24 coil
33 fuel pump relay--in this case you would not hear the pump but instead waited 3 seconds after the on / off sequence

update: Code 35 on Magnetti-Marelli EFI Systems
Normally a code 35 is set when there is a problem in the tachometer circuit. We
have identified another possible cause for a code 35 not specifically covered in the
Service Manuals. It pertains to a current or recurring historic code 35 (Tachometer)
on 1995-2001 EFI Touring models including Road Kings not normally equipped with
a tachometer. This code may be accompanied by codes 41, 42 or 56 and perhaps
even hard starting, poor cold idle and driveability issues. The ECM is functional
because it still has Key On power at pin 26.
Diagnosing this possible condition is relatively easy. Using the Scanalyzer, look for
consistent battery voltage in the data monitor mode (you may have to perform a
wiggle test while monitoring) because the Scanalyzer is monitoring voltage at pin 35
of the ECM (not battery voltage across the battery terminals). Closely inspect every
connection from the Main Circuit breaker to the ECM for loose crimps or
connections. Even a loose ECM fuse or intermittent ECM relay can cause this
condition.

 

It was my understanding parts are hard to find and the M&M is hard to tune or find someone to tune it. Isn't it common knowledge the M&M can be problematic?
No problems now, but I am not going to carb when the time comes so trying to identify my options in advance.

 

I don't have an MMI bike but do have two later EFI bikes, I've also owned Harleys a very long time. Unfortunately some owners are, to be blunt, dynosaurs, and will make a fuss about anything they don't like, especially if it involves electronics, so some of the anti-MMI stuff is just rhetoric. Never mind that H-D introduced electronics long before BMW did and have used it since before many members were born! By contrast in im above we have a member who knows and understands MMI, so be guided by him - he is genuinely one of our experts.

 

I run a Megasquirt based system on the Sportster. I will eventually do my bike and probably the chopper.

 

Parts are readily available. The only adjustments that can be made to the M&M system are the hot and cold idles, and the throttle position sensor. Everything else is fixed. Finding someone who knows anything about it can be a problem. The best thing to do is learn how to work on it yourself.

One thing to keep in mind is that the M&M system does not like for you to change the cam. Leave the bike stock except for mufflers and intake and it will be happy. With a cam change you will need a programmable computer.

carl
M&M Road King