My son was looking for a bike and someone told to be careful of the fuel injection system and or fuel injectors on the 2001 touring bike he was looking at. Don’t know how many years in either direction he was talking about. Has anyone heard of this ?

 

The 2001 EFI HD's have an injection system by Magnetti & Marelli. It was available as an option from 1995 through 2001. The system does work, but there a fewer and fewer people who understand how to work on them. Parts are also becoming scarce, but still obtainable. The system can be a bit quirky, and it seems the more mods that are done the quirkier it becomes.

The field service manual has a very good diagnostic flow chart to help keep the system up to snuff. Other people will convert the EFI system to a carbureted aspiration system which can be done for somewhere in the neighborhood of $700 if you do it yourself to $1500 to have a shop do it.

Things that seem to pop up with the M&M EFI bikes are Engine Temperature Sensor, Idle Speed Control Motor, and Throttle Position Sensor failing, in that order. None of these are difficult, nor expensive fixes.

 

In 2002 HD began using The Delphi injection system which I have never had a problem with on two different bikes. Personally, I'd never buy a bike with the M&M system....you DO NOT want a bike that is not dependable.

 

Seems to me a lot of the fear about the MM system is internet hype. I put over 130,000 miles on my first 2000 Roadglide and another 80,000 on my second 2000 Roadglide without any fuel problems at all. As long as you leave it near stock you won't have any more issues than you might on any bike that is 17 or 18 years old to begin with. If you want to make big changes, that's another story.

 

Again as stated by others I believe you will really only run into problems with the Marelli ignition when you start to do significant performance upgrades. Two of the guys I ride with are on pretty much stock stage 1 Road Kings one is a '99 and the other '2000. Both have the Marelli ignitions and both are trouble free.

If the bike is a great deal and you plan on doing significant performance upgrades there are options. Zippers has a conversion kit complete with a Thundermax tuner, Delphi style throttle body and high flow air cleaner. This would allow you to run a canned tune from Zippers and Auto Tune which could save you the cost of putting your bike on the Dyno.
Over all it is pretty expensive, probably $1300 more than going with another tuner and paying for a Dyno but if the bike is a good deal it could be a wash.

http://www.zippersperformance.com/th...e-marelli.html

 

In my opinion, the Delphi injection system is as good as the MM was bad. I survived many years with the MM on my 2000 FLHCI, and I became in involuntary expert on the system. It worked because I was attentive to it, but I don't think I ever did get it right.
Add to that experience the fact that parts are now difficult if not impossible to get and the further fact that the MM EFI got worse mileage than a carb of the same year and way worse than the Delphi, the only way I'd get a bike with that system is if it were such a good deal I could economically convert it to a carb.

 

My former 01 had mm injection. I didnt know any better when i bought it. I had a reputable engine builder tell me to just go carb but the choice was mine. Knowing what i do now about tuners i wouldnt get one with anything other than delphi. Mm can be a pain in the ***.

 

Most M & M problems in my opinion are due to individuals and techs failing to read the one fuel injection chapter in the service book.
They want to "know" without reading.
You read 30 pages and gain a wealth of knowledge.
Then you learn you can read computer codes without tools through speedometer.
They are dependable bikes and there are plenty of them on the road.
Several high mileage examples on this forum and a few with engine modifications.
Their history is well known and common ailments are easily addressed.
These are bikes from 1995 to 2001..that is a long time ago for some techs that work on stuff only 1 to 3 years old..
M & M is a very simple system with very few components.
Most people forget it is a system used by high dollar vehicles.
Since it has not been used by Harley since about 2001 there are few Harley techs that will take the time to read the one chapter in the service book on fuel injection.
Techs work on book time so it is more lucrative to work on the bike they see every day and do not need to read about...so most say "oh M & M that is a problem" but are not able to clearly say why....it is because they have little knowledge but will not tell you.
They did not want to read the one chapter.
It is like taking a Harley with a carb to a newer tech...some have no idea how to change a needle or adjust carb since use stopped before their time.
Heck, there have been folks that converted from M & M to carb because they failed to catch a simple common loose connection of the crank position sensor or got frustrated and sold the bike...because they did not read the one chapter...numerous folks have come to this forum frustrated after taking the bike to a mechanic and been saved big money on this forum when the problem was explained about the engine temp sensor, a bad cam sensor, a loose crank position sensor connection, leaking gas line, trash in the tank or some other simple problem...the reason, nobody wanted to read the one chapter of about 30 pages.
Larsfum explained it well and in detail.
You should have the service book for any Harley purchased regardless of fuel injection system.
Even if you do not work on the bike yourself, the knowledge will allow you to understand and communicate how to fix it.

 

My 2000 has been relatively trouble free for 58k miles even with the engine mods at 38k dyno tuned @ 100 hp. The tech did have to tune it on the rich side to get rid of decel pop so my mileage went down from 40 to 30 but I live on an Island and never go through a full tank in one day anyway. I have a hesitation accelerating quickly from just over 2000 rpm but no where else. I am going to try the tank issues first, then sensors and then??

I posted a question a couple days ago but got no replies -

https://www.hdforums.com/forum/touri...l#post17020667

It seems the Thundermax may be a solution for about the same price as a carb conversion and a lot less hassle if nothing else works.

 

If your mileage went from 40 to 30 then the tune is way off and the mechanic was throwing fuel at a problem instead of fixing the true problem...are you running open pipes with zero back pressure?
Do not just replace sensors..test them.