96 Ultra Classic. EVO motor. Have owned it for a couple of months. First month ran great. Second month not so great. Had a temp sensor replaced and new intake gaskets installed and she still runs lousy. Went from 51 MPG to 27 MPG. Sputters at speed and Harley can't get it to replicate. Some suggested a map sensor. Also smell a lot of exhaust when riding. Plugs were also replaced. Help. I love this bike but I need it to run right. Thanks.

 

Its EFI right? And MM EFI into the bargain......it needs proper diagnostics, assuming the air filter isn't blocked or the brakes binding....or convert to carburettor and enjoy a simpler life.

 

Can I really convert it to carbs?

 

No map sensor on a MM bike. Harley sells a service ECM to replace MM ECM. Unit is actually sold to Harley from S&S. Part # 41000012A. Kit comes with CD pro tune software. Use Harley Stage 1 map that is in the software. Software has gauge functions that will make TPS and idle set up easy. No more need for diagnostic tools. Kit is direct hook up to Harley wiring harness. My bike had all your same problems. All gone now and she runs better than new.

 

Do you know if it has had any upgrades to the ecm? Here is a good info post.

https://www.hdforums.com/forum/evo-c...injection.html

Search is the key on that type of efi.

 

Thanks 92fatty. Helps a lot. I am going to pick up my machine from the dealer tomorrow. They told me that they couldn't get it to replicate. I love this bike and don't want to be soured. I have a gold wing in the garage and would much rather ride my Harley.

 

Yes here is a link to convert your tanks to carb set up

http://www.pingelonline.com/magneti_...conversion.htm

You will also have to get a new intake and carb of your choice.

Good luck

 

BAKINS, carb isn't necessarily the answer. In fact with today's fuel and future poor fuel we will be buying, a carb is the last thing I would do. Ethanol eats rubber, so this opens up a whole bunch of future problems with carb set-ups. Carb technology is old and EFI is the future. Most people on this forum do not understand EFI systems, specifically the Magneti-Marelli which is in your bike. The main problem with a MM system is the ECM. Face it the Italians sold Harley a very temperamental system back in those days. Read my previous post about the Harley replacement ECM (which is made and sold also by S&S). It is a modern windows based system that works with all your current sensors. Which your bike has six sensors plus two injectors. The program will check sensor operations on the gauge screen, so you will know if they are good are not, no need for expensive scanilizer tools. If you can download a program on a Microsoft based PC, you'll have no problem running and tuning the bike. Most HD dealer mechanics don't have a clue on MM injection, unless he's older. I know because I was one and have fixed many MM problems. Plus, MM bike can have many power upgrades and run right with or ahead of carb bikes. I'll put my EV 27 touring bike with MM up against a carb bike with the same mods. Let me know and I'll post more.

 

If you can score the above ecm that is programmable that is the route I'd take. He's right about the dealer knowledge also. I'm surprised they took in an evo for work.

 

I'm surprised as well on the EVO work. First step is to get Harley part # 41000012A. This is the same ECM as S&S cycle model VFI #55-5006 (S&S web site, click evolution, click electronics, click VFI). S&S cost is +/- $620, but Harley is only a little over $400. Get the Harley part, because the CD pro tune software will have the MM bike Stage 1 and Stage II maps. If the bike is stock us stage I map. It's a tad better (richer) than the original MM map that was in the bike originally. After you have the software on a PC, you can go to S&S's web site and download their software also, which is compatible with the ECM from Harley because its S&S. The S&S software has more adjustment parameters than the Pro Tune included with Harley kit. S&S software is a free download and has 50+ more maps. Once you have the ECM in the bike, we can get you running smoothly. If a couple of sensors are bad, you'll know it from the software. Sensors are only $80-100 bucks ea. Chances are you need two, engine temp (located in the front head) and crank sensor (notorious for going bad with higher miles). TPS and BARO sensor rarely go bad.
If you want to go with upgrades such as a cam, heads exhaust, it's easy to use STAGE II map that is included in the kit and build from there.