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Old 15-04-2010, 08:50 PM
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Barry Boy Barry Boy is offline
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Magneti Marelli EFI to Carburetor Conversion

Now before anyone tells me that EFI is great and that it’s the way to go let me tell you about my experiences with it. Having had two previous carb fed Harleys which ran great the M&M EFI system on my 1996 Electra Glide was a pain with its only good point being cold starting and fuel consumption.

I’m sure the new TC and aftermarket systems do a fine job but the poor old M&M was too complicated for the DIY workshop but too simple to work properly.

I wasn’t the only one to have problems mind, I had someone else with an identical bike to mine who told me he never had any issues in traffic with his bike and then proceeded to pull away with the bike pinking so hard it sounded like a steel band warming up and a couple at Hogging the Bridge last year who didn’t realise their bike shouldn’t really be ticking over at 2,500 rpm when stopped at a set of lights after a very long and very slow ride over the bridge and with an engine so hot it was blistering the paint on shop fronts as it went by!

In an attempt to get the bike to play I fitted a DFO, replaced sensors, put a later 98 processor in it and had it tuned by a respected independent and a main dealer. In the end when ridden hard it went well, but no one could cure the poor thing of its wandering tick over, extremely high heat when in traffic and going to a high tick over for a few seconds when starting. As an engineer by trade I felt the bike’s pain.

I know what your thinking, intake leaks, so did I, but I changed the manifold seals twice and both the above shops changed them as a matter of course. I even Non Destructive Tested the injector manifold looking for cracks!

The advice of mates was to sell it and get something else, but I liked the bike and anyway I don’t like being beaten by an inanimate lump of metal.

The final straw came on a ride to West Wales last autumn. Stuck in traffic next to a mate’s 99 Softail which gently plodded away at about 850 rpm and mine sounding more like an R1 than a 1340.

I had already thought about what would be needed for a conversion but as most conversions you see on the web are TC88’s so I wasn’t completely sure. Then as luck would have it Kiwi posted on the forum about an unrelated problem but mentioned that his mate Martin had done the conversion with a 98. A few e-mail’s later and Martin had filled in all the blanks.

My ideal set up would have been a 42mm HSR carb and a Crane Hi-4 single fire ignition set, but as I’m tight, sorry careful it was back to rummaging in the spares box and several other peoples come to think of it! The final set up being a 40mm CV fitted with an SE air filter and S&S jet kit. Evo manifold with the restrictor removed and SE ignition unit, leads and coil. The only new items being VOES switch, leads and the coil which came from Jersey HD.

All the old bits were removed which did away with so much wiring it now look’s quite bare under the seat. A new ignition wiring loom was made up using the diagram for the carb model in the service manual, I bought one new Deutsche plug but re-used one off the end of the now removed EFI loom, did I mention I was tight.

Module now lives where the CPU did with the new ignition loom protected with Spiral Wrap.

The ignition timing cup needed changing for the carb models, the EFI ignition/cam pick up works but the cup is totally different.

The only fiddle was cutting the welded-in steel pipes in the fuel tank. The return line can be left alone as it only runs over the saddle in the tank and is blanked later on but the pressure line needs to be cut off fairly flush with the bottom of the tank as that’s the one the fuel tap will use. Careful use of a pad saw removed the pipe and its brackets, leaving the welded in threaded boss. Both the non return valves were removed by using a pair of needle pliers rather than the HD tool. The flutes of a drill were gagged with tape to protect the threads and the boss was carefully drilled out leaving just a threaded tube. This unfortunately also has to be cut down as you would end up with about a gallon left in the tank and no reserve. Working from outside the tank using a combination of rotary files and abrasive discs the tube length was reduced to about 5mm.

Original return line with the cut down feed ready for the Pingel adaptor and tap.

During the cutting and grinding I positioned a small magnet near to the boss which caught most of the debris.

Hair Bear Bunch.

Now for the expensive part, well to me anyway. Unless you’re handy with a lath and some stainless steel bar you will need a Pingle EFI to Carb adaptor kit which consists of a blank for the rear port and an adaptor to take a fuel tap in the front port where you have removed the boss. Please note that there are different kits for both Evo’s and TC’s so make sure you order the correct one, see the Pingle site.

If you want to use a cheaper aftermarket tap you will have to remove the filter screen and fit an inline filter as the hole in the adaptor is too small or you can bite the bullet as I did and buy a Pingle tap. I have to say the Pingle kit is beautifully made and works a treat.

Just about done.

The rest was simple, I guess timed the ignition, put the jets and needles in as recommended by the S&S instructions, fuel in, ignition on and she fired straight up even settling into a nice even tick over. To say I was shocked and pleased was an under statement!!

Well how has it worked I hear you ask? “Bloody brilliant is my reply”. Whilst the bike no longer starts like a modern car and she burns a bit more fuel, every other aspect has shown a marked improvement. She ran well straight away once the ignition timing was adjusted and as I have played with the jetting the performance has got better and better.

As a 1340 Electraglide her performance is never going to set the word on fire but with the two into one Supertrapp and the bolt in cam previously fitted the change to carb has made the bike feel re-born, my only regret is that I didn’t do the conversion on the second day of ownership.

The cost of the conversion was about 225 of which 100 was the Pingle tap and adaptors.

I just want to thank Kiwi, Martin, Matt’s Machine Shop, friends Mike and Andy and Blenk from Jersey HD.

Now where did I put that old bottle of winter additive?
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Old 15-04-2010, 09:08 PM
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devon.john devon.john is offline
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Re: Magneti Marelli EFI to Carburetor Conversion

well done mate, i converted my bike two years ago twin cam efi to carb
a little more expensive than you but a darn sight easier!!!
theres a thread i put on here when i did it (injection to carb )
i used the German ignition module p3 this is a very simple way to conv.

but you've managed to do it on the cheap to me that Evan better!!!

are you going to TALGARTH it would be great to see your bike and meet you.

(old iron ass)
FXDX 1550 played with the fast one
Royal enfield winter hack
1980 FLH80 the old one
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Old 15-04-2010, 09:20 PM
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Barry Boy Barry Boy is offline
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Re: Magneti Marelli EFI to Carburetor Conversion

Hi John

I'll be there, flicking burgers and pulling pints.

I did read your thread, very good. You are the only person who has reported back with long term findings. I've done about a 1000 miles since the conversion but so far so good.
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Old 16-04-2010, 04:01 AM
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kiwidave kiwidave is offline
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Re: Magneti Marelli EFI to Carburetor Conversion

that's a GREAT post and a potential big help to those ''forgotten few'', late 1990s Evo riders with fuel injection.

Brilliant work!

I would suggest this gets transferred to Tech Tips for posterity.
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Old 18-04-2010, 06:21 AM
Scotty Scotty is offline
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Re: Magneti Marelli EFI to Carburetor Conversion

Well done mate

Funny you should mention this right now but i just converted my XR1200 to carb the other day

Used the same ignition unit as devon.john

Was a bit of a challenge coz i had to work my way round getting rid of the oil cooling to the cylinder heads ( i dont need it any more as the bike runs a damn sight cooler with the carb) Another bonus is i got rid of about ten pieces of electronic widgets and thinymabobs that can all stick a finger up your arse when you least expect it.

Must admit, i took great pleasure in removing that ferkin witchcraft from my bike

Now its gonna be far easier to tune the motor when i chuck some decent cams in there along with some fettled heads and up the compression.

And as you can see my softail in the background doesn't suffer from the evil EFI infliction either!

Last edited by Scotty; 18-04-2010 at 06:40 AM.
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Old 18-04-2010, 12:26 PM
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Barry Boy Barry Boy is offline
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Re: Magneti Marelli EFI to Carburetor Conversion

Hi Scotty

Agree with you completely. The bike seems to run better but it's hard to say why, just seems happier? maybe it's just in my head? But it does run much cooler, I can feel that and the sound is a lot different, back to its old loping best with no random tick over in traffic.

The early efi bikes seem to be simply carb models with the injection system grafted on. Now the removed bits are living in the shed in two cardboard boxes, best place for them.

The hardest job you must have is deciding which bike to ride, now let's see what sort of mood am I in to day, LOL. Nice Super Trapps.
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Old 21-04-2010, 04:14 PM
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Spice Spice is offline
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Re: Magneti Marelli EFI to Carburetor Conversion

I`m sure your right and a carb is much more, versatile jet sizes etc etc but my 98 evo, has the first type of Magneti Marrelli fuel injection, which everyone has warned me about and apart from the high tickover speed which after a while settles down. and I am also informed is better for oil pump circulation when the engine needs it most at start up warming period ,it runs good as gold, last year fitted a Kitech performance module piggy backed onto the injectors, which just slings more petrol in at every squirt, this has had the effect of upping me fuel usage but has stopped the throttle lag that was a bit of a pain, and the top end seems to have an extra ten MPH. so ,so far touch wood its
the good old Italian EFI for me......... till it goes wrong of course..
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Old 21-04-2010, 05:03 PM
grbrown grbrown is offline
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Cool Re: Magneti Marelli EFI to Carburetor Conversion

I can understand wanting to ditch the earlier EFI system, but I must say my Buell runs very well. I think I can keep my hands off that!

Being a bit of a dynosaur myself my old Glide has accumulated more electrickery over the years than easily fits in it and that is just to do things to it I want!
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Old 30-04-2010, 11:25 PM
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Simon Simon is offline
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Re: Magneti Marelli EFI to Carburetor Conversion

Andrew, Scotty,
Kudos to the pair of you. Very impressive stuff.
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Old 01-05-2010, 12:34 PM
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Barry Boy Barry Boy is offline
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Re: Magneti Marelli EFI to Carburetor Conversion

Hi Simon.

Thanks for that, my efforts are small beer compaired with what you have achieved whith your Dyna.

It sounded sweet going up the hill out of the field at Talgarth by the way.
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