Magneti Marelli FI

[Sinker]

I read a lot about MM fuel injection units going bad. I have a 2000 Road King Classic with thia fuel injection and it seems to run ok. What is the reason people replace these? What are the reasons  behind they fail? How long do they last before people are replacing them?

[Skin]

can't get parts for them, I've got one on a '96 Ultra with 116k on it and it still runs, idle wont adjust but it runs. When they run their good but when they don't your done. I'll be doing a carb on the bike if it doesn't sell.

[Don D]

They are fine and simple. With all the conversions that happen there are a lot of used parts available. They are not a good choice for performance use but just a good running stock or mild performance 80-95" motor

[chaos901]

They are fine and simple. With all the conversions that happen there are a lot of used parts available.

Interesting point that I need to consider.  I have MM on my 2000 RG and was worried about finding parts.

[PC_Hater]

Fault-finding gets far too exciting when EFI gets old.

Swapping known good parts is the easy way but that means you need a stock of parts.

One possibly useful bit of info: If you fit the MM ECU from an EFI EVO to a Twin Cam 88 in a mild state of tune the bike will start and run!
It coughs and farts and bangs but it does run. It meant I could confirm that my problem was NOT the MM EFI but I had had enough by then, so the carb conversion got done.

[Pirsch Fire Wagon]

At the time the MM EFI was used (1995) it was a good system at the time. But, nothing remotely capable of today's abilities to control the Engine (and additional on CANBus). Today's EFI is virtually self-diagnosing in most instances. And, designed to expand an last 10x that of it's predecessors.

With that being said, what you're fighting here is not the system but age.

Example: About two years ago I tuned a MM. Finished the invoice and called the customer. When he arrived the Motorcycle would not start. After eight hours of troubleshooting (@100.00 Hr which I din't charge) I found a broken wire in the 32 wire hairless under the tank on the back bone.

Many in the industry refer to the MM and me as well as "The Marelli Factor" when working or Tuning them. They are simply archaic compared to today's systems. What took 32 wires to operate them now uses only one wire on a CANBus system to communicate the same essential information, often overtaxing the ECM. Especially when Hot or Very Cold ambient temperatures exist.

In a nutshell , the huge difference between these systems (MM (Alpha-N-1) /Delphi (Speed Density) on the MM throttle position and RPM determine the amount of fuel to deliver. An intake air temperature (IAT) sensor within the throttle body to make adjustments to the fuel mixture. A problem with the sensor in the MM system was that the measured air temperature was not an accurate reading of what the intake temp really is seeing. Relying on temperature close to a hot motor was not the best way to determine intake air temp. When the air enters the venturi of the throttle body, it speeds up, thereby changing its temperature. In addition, the throttle body, it sits right above the hot motor, compounding the problem of accurate air temperature measurement. For performance motors, the dual-plenum throttle body, with independent runners feeding each cylinder, was too small to pass the required air into the engine. An advantage of throttle-based control is that there's no dependence on intake-manifold pressure, which benefits motors with radical cams.

[Don D]

A comparison to a Delphi is apple's and peas. It is a crude system nonetheless reliable. With a few spares in the saddlebag you can travel worry free. Guys give up and dont take the few easy steps to troubleshoot them if there is an issue. Then rush to a carb fix. If I had one and was in love with it I would swap to early Delphi 2005 with closed loop and acrs. Not cheap and easy by the way.

[Scotty]

Example: About two years ago I tuned a MM. Finished the invoice and called the customer. When he arrived the Motorcycle would not start. After eight hours of troubleshooting (@100.00 Hr which I din't charge) I found a broken wire in the 32 wire hairless under the tank on the back bone.

That there is probably one of the truest statements you will ever read.
You work on a old bike and everything is now your problem 

[Scotty]

A comparison to a Delphi is apple's and peas. It is a crude system nonetheless reliable. With a few spares in the saddlebag you can travel worry free. Guys give up and dont take the few easy steps to troubleshoot them if there is an issue. Then rush to a carb fix. If I had one and was in love with it I would swap to early Delphi 2005 with closed loop and acrs. Not cheap and easy by the way.

The big "IF" though is that a lot of people don't work on or understand MM EFI anymore and the guy riding the bike may not know much either.
For you what seems easy could be so overwhelming for a normal person a carb conversion could be a good solution especially at today's labor rates to diagnose and fix faults.

[Don D]

ersonally I would have no issue with a carb either. My 2002 had a cv51 and ran well and every day. Btw the factory SM has a good description of the MM injection system for those that own them and want to take the time to learn what's going on there plus how to set the idles.

[Moparnut72]

Magneti Marelli was owned by Fiat. They just recently sold that company but i don't know to whom. I just bought a new Moto Guzzi and they use an EFI by that manufacturer. It works as well if not better than the Harley I owned.
kk

[Pirsch Fire Wagon]

Magneti Marelli was owned by Fiat. They just recently sold that company but i don't know to whom. I just bought a new Moto Guzzi and they use an EFI by that manufacturer. It works as well if not better than the Harley I owned.
kk

CK Holdings Co., Ltd. owns Magneti- Marelli

Magneti- Marelli is perhaps the Number One in the field of E.F.I. And, has been for eons. Just about every Europien and Asian Motor-vehicle has a MM. They are used elusively in many Race Circuits.

As for the MM of H-D, they were as capable as any in their time-frame. The HD's are just obsolete. And, pretty much anything else from that time-frame also.

On the other hand, I have a 7.3L DIT Diesel which I wouldn't trade for the $100,000 Truck sold today because of EPA Standards. There are many reasons to keep and maintain an older system.

[Pirsch Fire Wagon]

A comparison to a Delphi is apple's and peas. It is a crude system nonetheless reliable. With a few spares in the saddlebag you can travel worry free. Guys give up and dont take the few easy steps to troubleshoot them if there is an issue. Then rush to a carb fix. If I had one and was in love with it I would swap to early Delphi 2005 with closed loop and acrs. Not cheap and easy by the way.

The big "IF" though is that a lot of people don't work on or understand MM EFI anymore and the guy riding the bike may not know much either.
For you what seems easy could be so overwhelming for a normal person a carb conversion could be a good solution especially at today's labor rates to diagnose and fix faults.

Many Harley-Davidson Dealerships will do everything possible to avoid them. Many won't work on them - period. I have been referred by a few, as well as after market shops. And, the only reason is that I was alive and breathing working for HD when they were the only EFI.

The sad part is I have to buy just about everything as NOS or eBay or Used Cycle Sites. With the exception of the Fuel Pump (and it may have been obsoleted since the last one i purchased), juts about everything is Obsoleted by the MoCo. As with anything that ages. Myself included.

They're not difficult by any means. The problem's with many, not all, is you can't plug a computer in and say for certainty "that's the problem". I'm NOT knocking Technicians. But, to some extent, that's the newest generation working in Shops.

Harley-Davidson just completed a very in-depth study of all their Divisions. Currently, the national average of turn-over in Dealership Technician's is 41% annually. Sure there are many reasons, but, regardless of the Training - the real training is Hands-On with someone as your "Go to Guy". I've been doing it for 32+ years and I still have my go-to-guys when I'm stumped. MMI and others do a good job of getting the Students up-to-speed and in most cases, employment.

The technoresearch centurion super pro is actually better than a Snanalyzer (I haven't used mine in a decade - just takes up space) or DT-II IMO for PID's.

Ultimately, knowing how to work a DVOM with some specific accessories as well as the Parts Specifications is a must.

[BVHOG]

100 percent done with servicing or tuning the MM injection. Too hard to find parts, throttle shafts worn making proper adjustments impossible and basically making your life hell while trying to sort them out along with a 20 year old wiring harness. Carb swaps make them a better bike then they ever were even when they were new.   
A friend of mine who is a service writer at a dealer was asking about the Techno research stuff and I told him it was the same guy who developed the MM for the moco. His response was "that guy must wear a nut cup 24/7"

[Hossamania]

One good thing to come out of the MM was the shorter primary gearing. Works great in my '01 carbed King.

[Pirsch Fire Wagon]

A friend of mine who is a service writer at a dealer was asking about the Techno research stuff and I told him it was the same guy who developed the MM for the moco. His response was "that guy must wear a nut cup 24/7"

I'm pretty sure the Founder was an Automotive Engineer. In fact, I'm certain of it. I don't know who his partners were. They may have been MM People. I know one worked for a Major Motorsports Division, don't know which one, perhaps Polaris. Just a guess.

For the Money (I have the whole system) you can't beat TR. I can do anything I could do at a Dealership. I don't know of any similar systems.

It is comparable to the DT-II. They're always improving it. What impressed me was; I was Tuning a Bike (Delphi), and there was an issue with VE/MAP. When I called I got immediate service and the Technician remotes in on the computer, changed some settings and said change a sensor (I forget which one). When I did, it tuned flawlessly.

By far, it's the absolute best and most user friendly. Much easier than DT-II and you can use it and by-pass other ECM's like Zippers to program the BCM and Radio Function. I also like you can choose Narrow or Wide band as well as Analyzers in Direct Tune or Auto Tune. There is another company in Europe or the UK which has a similar system. But 2x the price.

The only draw back is in Auto Tune, the VCM only stores about 20 minutes. But, speaking with them, they're looking to increase that to 60 minutes. Dynojet has more storage but has a dedicated Computer. You don't need to dedicate an entire computer with TR. With Bluetooth and Android OS will work as well.

BTW: Their training program (3 Days) in Mississippi was great - Hands on Tuning and Diagnostics. Classroom was only about two hours daily. The rest was actually doing it with instructors. $1,400 for everything except transportation. Hotel, Food, Classroom, Books, etc., all included.

For an aftermarket shop - it's the way to go.

Now that I have written all this, they'll go under!!

[FSG]

BTW: Their training program (3 Days) in Mississippi was great - Hands on Tuning and Diagnostics. Classroom was only about two hours daily. The rest was actually doing it with instructors. $1,400 for everything except transportation. Hotel, Food, Classroom, Books, etc., all included.

I've done various courses (no EFI stuff) around the world, a lot in Houston, some in Tulsa and some in New Orleans just to mention some of the USA ones and $1400 for 3 days excluding transportation is IMO a steal.

[BVHOG]

A friend of mine who is a service writer at a dealer was asking about the Techno research stuff and I told him it was the same guy who developed the MM for the moco. His response was "that guy must wear a nut cup 24/7"

I'm pretty sure the Founder was an Automotive Engineer. In fact, I'm certain of it. I don't know who his partners were. They may have been MM People. I know one worked for a Major Motorsports Division, don't know which one, perhaps Polaris. Just a guess.

For the Money (I have the whole system) you can't beat TR. I can do anything I could do at a Dealership. I don't know of any similar systems.

It is comparable to the DT-II. They're always improving it. What impressed me was; I was Tuning a Bike (Delphi), and there was an issue with VE/MAP. When I called I got immediate service and the Technician remotes in on the computer, changed some settings and said change a sensor (I forget which one). When I did, it tuned flawlessly.

By far, it's the absolute best and most user friendly. Much easier than DT-II and you can use it and by-pass other ECM's like Zippers to program the BCM and Radio Function. I also like you can choose Narrow or Wide band as well as Analyzers in Direct Tune or Auto Tune. There is another company in Europe or the UK which has a similar system. But 2x the price.

The only draw back is in Auto Tune, the VCM only stores about 20 minutes. But, speaking with them, they're looking to increase that to 60 minutes. Dynojet has more storage but has a dedicated Computer. You don't need to dedicate an entire computer with TR. With Bluetooth and Android OS will work as well.

BTW: Their training program (3 Days) in Mississippi was great - Hands on Tuning and Diagnostics. Classroom was only about two hours daily. The rest was actually doing it with instructors. $1,400 for everything except transportation. Hotel, Food, Classroom, Books, etc., all included.

For an aftermarket shop - it's the way to go.



Now that I have written all this, they'll go under!!

If Sandro was teaching the class I would be there in a heartbeat, the other guy no thanks.  And what are  you going to do with the mm system when you need a new ecm?  The S&S stuff doesn't work with the Techno stuff

[Pirsch Fire Wagon]

The "Techno Stuff" has nothing to do with it. S&S (as many) has proprietary Software for their Units.

There are a couple options:
1. Zippers sells a replacement ECM currently ($895)
2. Zippers also sells a complete conversion to their EFI System ($2,500 depending on options) I have done both systems with success.
3. S&S No longer produces the VFI Domestically (uses S&S Software). These were Harley-Davidson replacements. Some NOS is still available across the pond. eBay is always an option.
4. If you have an MM and want to keep it, the best idea would be to be start stocking up now.
5. Convert to a Carb System
6. There is a company who produces a Hybrid System. Although, their names escape me.

[BVHOG]

The "Techno Stuff" has nothing to do with it. S&S (as many) has proprietary Software for their Units.

There are a couple options:
1. Zippers sells a replacement ECM currently ($895)
2. Zippers also sells a complete conversion to their EFI System ($2,500 depending on options) I have done both systems with success.
3. S&S No longer produces the VFI Domestically (uses S&S Software). These were Harley-Davidson replacements. Some NOS is still available across the pond. eBay is always an option.
4. If you have an MM and want to keep it, the best idea would be to be start stocking up now.
5. Convert to a Carb System
6. There is a company who produces a Hybrid System. Although, their names escape me.

7. Convert to Delphi with parts from Dan Thayer.  Oh, and well aware of the S&S systems and did the classes there for VFI years ago.

[kink04fxd]

One good thing to come out of the MM was the shorter primary gearing. Works great in my '01 carbed King.

This is true.

[booker49]

have one one my 2000 rk. every year i take off the air filter, spray carb/fuel injecter cleaner with the thin red hose, in every hole thats there. i do this a few times, leaning the bike over with the throttle open (not running) this cleans it out and with 130,000 miles, it runs like new.