I see a lot of comments about how bad the Magnetti Morelli EFI is but what is it exactly that is so bad about the system?

 

I picked up an 01 EG Classic with that system last year with 132 k klms on it and it runs great.I really don't see why they would be any different than any other system out there.I had heard that parts were hard to get but apparently they're still in business so I don't know about that.I think a lot of it is that people prefer the simplicity and cost of the old carbs.Sure is nice to start and walk away though.I picked up a 2012 Ultra near the end of the summer and while the 103 has a lot more ***** I can't really say that it runs better.JMHO.

PS I've worked on FI since it got big in cars in the 80's so maybe that why it doesn't concern me as much.

 

It's not that bad of a system. But it has gained the reputation because of resistance to change back in the day and repetition of that sentiment has become its legend.
One book that discusses the Magnetti Morelli EFI is "Donny's Unauthorized Technical Guide, Volume III: The Evolution: 1984 To 2000", by Donny Petersen.
Peterson gives a fair assessment of the MM EFI. He gives good explanations of the various sensors.

 

Well that's the thing right.The sensors are basically the same on everything that's injected.There are some differences between systems but basically all the same.

 

I have a 98 RKC (fuel injected).

The biggest weakness is the head temp sensor. It's not all that reliable and is prone to failure. I've put several in my bike over 90k+ miles. Other than that, you need to understand the system in order to work on it and tweak it just a little. There actually isn't all that much that's even adjustable. Parts are getting hard to find. The throttle position sensor is absolutely not available. Luckily, it's pretty reliable. An additional complaint is that if you want to hop up your motor, there isn't much you can do with the stock EFI. There used to be larger fuel injectors available that might help to a point but if you want super go-fast, you'll have to convert to a carb.

My bike has the stage 1 upgrade which is just a free flowing air cleaner and less restrictive mufflers. It also has an aftermarket cam (Andrews EV27). The cam is designed to give more torque at lower rpms and makes it so you don't have to downshift as much as with the stock cam. It runs great and for the most part has been a reliable bike. If more new MM EFI bike owners would take the time to llearn and understand their bikes, they wouldn't have nearly as much trouble. Usually, they give up right off the bat and put a carb on it.

carl

 

Road King classic 1998.
EV13 cam, K & N air filter.
Modified slip-on mufflers.
If you ride an older bike then you need to know or want to learn about maintenance.
Not because bike is bad but because few young mechanics will know how to service.

 

Well asked the question because I recently bought a 99 Road King Classic with EFI with only 18k on it but its been sitting for quite some time (only 1880 mies put on it since 2009 and sitting for the last 6). I have had Harleys for years and I currently have a couple muscle cars as well so I'm not afraid of wrenching at all.
Its just this is the first EFI bike I have owned and all I hear is negative comments about the MM system so wondered exactly what is the issues with it?

 

There are no issues. It is a fuel injection. All sensors need to work properly. If attention needs to be paid to it, a confident/competent technician needs to attend to it. The technician must not just throw up his hands and yell "You need to convert to a carb".

 

I've owned my 2001 Road King since 2008 and besides replacing all the leaking hoses inside and outside the tank, I've had no issues with the fuel system. It runs as well as my newer bikes. Maybe better. I think issues are with tuning if non-stock engine, and repair parts availability. I haven't had either issue, knock on wood.

 

My 2000 FLHT came with M&M. It ran fine but seemed lethargic compared to my carbed bikes. Swapped to carb. Not hard to do.