What would it take to go from EFi to Carb

Mastiff Rider64

Mastiff Rider64

Well-Known Member
I'm already thinking of next winters project. I'm thinking of taking my 2009 Bulldog Bagger from EFi to Carb. But not sure what all I would have to do because of the VFI and ECH and installing a ignition module. I know I would need a new intake manifold, gaskets, I'd have to install a petcock plate in the gas tank, gas line, I'd have to install a Carb. But what all would be needed to do this? I searched for a forum that I once saw on here of someone discussing doing this but I couldn't find it.

The reason for this is because I continue to have issues with the set up on the bagger, check engine light coming on and going into limp mode, but checking codes and no codes, I crank the bike the engine light is off, having to have it dyno tuned several times because it doesn't seem to keep the crank and idle settings, spitting and sputtering after cranking sometimes others times I sometimes crank the bike and its rough idling and when I give it gas it revs up to 3500 RPM and just stays there till I cut the bike off, then the next time I crank the bike it may start just fine, seems that sometimes I'm still running extremely hot, with dual oil coolers on an 80 degree day in red light to red light traffic. I got in touch with S&S and they say they can get me a basic tune, but can't say that will fix the problems I'm having.

The local custom motorcycle shop here that was a bigdog service center up till 2011 that has been thru this bike over and over has run out of ideas. And the mechanic there is S&S certified and protune certified, but he even admits that he doesn't use protune enough to know all the in and outs of the software and he says that S&S has discontinued continuous education for mechanics on the software.

If anyone has any ideas I'd appreciate them greatly.
 
S

Sven

Well-Known Member
You'll need a Y intake manifold, a single carb or a swap meet Harley carb, an ignition plate for the cone, a cup for the ign plate. The Harley ignition box, a VOES sensor, a tapped nipple hole for the intake manifold for the VOES vacuum hose, or you'll code the box to run a 10° to 55°, not the more linear 10-40-55° ign curve. The petcock like you said, and maybe cables for the carb.

That takes out the EFI box, and now home make a wire harness for the lights, one brake light, no high beam wire but just swap it if the low burns out, swap the wire off the low to hot the high beam. Use hand signals and no need to add more wire to the winker setup. Ignition key moves to the hot coil wire side, and/or headlights with a second key turn [if applies],
 
awg

awg

Guru
Well people my 2009 bagger has this check engine light on most of the time. As soon as it's running, the light pops on. Never had a running problem with it though. It may be because when I purchased the bike it has, and still does, have a wire plus installed. Runs great with or without the light on. I think maybe it has some thing to do with the wire plus.
 
mleach72

mleach72

Well-Known Member
I am certainly not an auto electrician, but could it be as simple as installing a carb ehc and ignition module and disconnecting the efi stuff (sensors, fuel pump, etc.)? I would imagine the commonly shared stuff like lights, starter, etc. probably use the same circuitry. You would have to cross reference the outputs on the ehc. Maybe it's way more difficult than this, but worth looking into. Maybe talk to Curtis. I'm with ya on EFI. Great when working, but frustrating and expensive when something goes wrong. If you need an ignition module, I have a working stock module you can have. Of course, you would need the obvious stuff (carb, manifold, petcock).
 
S

Sven

Well-Known Member
Chopper wire harness = Basically strip down just to the basics. Solder male/female ends not crimp = Bulletproof harness. Ask me how I know, times 5 chopper builds from the ground up.

Simple trick is to think wire to ground, then the wire of the component's ground. Mount component, then hot wire to key switch/ toggle switch. Takes the confusion out of wiring. So it's one wire group for the running lights/brake light. One wire loop for the ign box to key switch. The pin-out of the spark box is easy to figure out if you have an OEM wire diagram and not any color wires being used.

Swap meet Harley wire harness in FI so you have more colors to group with, matching OE's colored wire to component. You'll forget what color when where if you found a japanese harness, then wire/color your own harness on a sheet of paper and save that for down the road, meaning.

Maybe fresh in your mind doing it, but a year/months later... good luck.

Signed,
Senior moments are a bitch
 
Jwooky

Jwooky

Well-Known Member
Sorry but its a terrible idea.

Understand you’re frustrated, but EFI is superior in every conceivable way.

We can help sort through your issues, and you will be much further ahead.

Most issues involve clogged or debris in the system due to sitting, tank liner etc.

Pump, regulator, filter and new line is ~$150.

Clean or send injectors out to be cleaned

This resolves 99% of problems
 
Mikeinjersey

Mikeinjersey

Well-Known Member
From your description it sounds like you have an intermittent electrical problem except for your engine getting stuck at 3500 rpm seems like a mechanical failure of the butterfly. I would have to assume that the mechanics have checked and cleaned all the related electrical connectors involved. I don't know if the BigDog EFI controller is known to be flaky. Have you swapped out or changed any of the sensors? TPS would be my first pick.
You could do as Jwooky suggests or at least change the filter.
My :2cents: Too expensive and problematic to change over to a carb system. Keep Troubleshooting!
 
Jersey Big Mike

Jersey Big Mike

100K mile club
An alternative plan might be to talkk with Daytona TwinTec about swapping to one of their EFI units (which with the proper harness will work with standard wide band o2 sensors (extra wires on 36pin delphi connector not wired on bdm's)

Neither route will be cheap.

Another option depending on your skill level is a Speeduino unit perhaps custom done for your bike.
Speeduino is an open source EFI setup that is quite robust actually and been around for years. This is likely my plan if my EFI goes out on my bike.
 
Mastiff Rider64

Mastiff Rider64

Well-Known Member
Jwooky said:
Sorry but its a terrible idea.

Understand you’re frustrated, but EFI is superior in every conceivable way.

We can help sort through your issues, and you will be much further ahead.

Most issues involve clogged or debris in the system due to sitting, tank liner etc.

Pump, regulator, filter and new line is ~$150.

Clean or send injectors out to be cleaned

This resolves 99% of problems
Click to expand...
I recently had both injectors replaced and it had the idling problem before and after replacement. The switching over is just an idea now. I did find a small gas leak from around the gasket at the tank for the fuel pump. Going to remove the fairings and try to take the tank off, but I've never removed this tank before. And heard it's a pain in the ass to do so. My Mastiff tank is easy to remove. So hopefully this one will be too.
 
Mastiff Rider64

Mastiff Rider64

Well-Known Member
Mikeinjersey said:
From your description it sounds like you have an intermittent electrical problem except for your engine getting stuck at 3500 rpm seems like a mechanical failure of the butterfly. I would have to assume that the mechanics have checked and cleaned all the related electrical connectors involved. I don't know if the BigDog EFI controller is known to be flaky. Have you swapped out or changed any of the sensors? TPS would be my first pick.
You could do as Jwooky suggests or at least change the filter.
My :2cents: Too expensive and problematic to change over to a carb system. Keep Troubleshooting!
Click to expand...
The TPS sensor alone is no longer available thru S&S. You have to buy a whole new Throttle Body. I actually got the last one Donna had from Erik a few years back. That is the only thing that controls the butterfly valve and also tells vfi how much gas is needed. I've thought for a while it could have gone bad that's why I checked with S&S and of course they won't tell me who their vendor is for me to go buy my own. They want to sell me a whole new unit.

I believe there is a post on here from 2 years ago or maybe a year ago. But the fuel pump, filter, injectors, fuel rail, temp sensor, map sensor, TPS sensor, intake air filter, and like 3500 dollars worth of stuff and labor was spent on this same problem I am having. The shop says that my pipes are to short allowing air to be sucked up to the O2 sensors causing the check engine light to come on and go off, but that don't explain the idling problems when starting the bike, whether a cold start or after 200 miles of riding.
 
Mastiff Rider64

Mastiff Rider64

Well-Known Member
Jersey Big Mike said:
An alternative plan might be to talkk with Daytona TwinTec about swapping to one of their EFI units (which with the proper harness will work with standard wide band o2 sensors (extra wires on 36pin delphi connector not wired on bdm's)

Neither route will be cheap.

Another option depending on your skill level is a Speeduino unit perhaps custom done for your bike.
Speeduino is an open source EFI setup that is quite robust actually and been around for years. This is likely my plan if my EFI goes out on my bike.
Click to expand...
From my understanding my bike has the S&S wide band O2 sensors. The ones in it now were bought by the shop that was working on it and the box from S&S they came in says Wide Band O2 Sensors, the shop gave me my old ones back in the box. And they did have to exchange the plug off my old ones and re-pin the wires of the new ones for my factory plugs to work.
 
Mastiff Rider64

Mastiff Rider64

Well-Known Member
Mastiff Rider64 said:
From my understanding my bike has the S&S wide band O2 sensors. The ones in it now were bought by the shop that was working on it and the box from S&S they came in says Wide Band O2 Sensors, the shop gave me my old ones back in the box. And they did have to exchange the plug off my old ones and re-pin the wires of the new ones for my factory plugs to work.
Click to expand...
But I will call Datonia TwinTec, my shop had mentioned them before about redoing my whole EFI system.
 
Jersey Big Mike

Jersey Big Mike

100K mile club
Mastiff Rider64 said:
From my understanding my bike has the S&S wide band O2 sensors. The ones in it now were bought by the shop that was working on it and the box from S&S they came in says Wide Band O2 Sensors, the shop gave me my old ones back in the box. And they did have to exchange the plug off my old ones and re-pin the wires of the new ones for my factory plugs to work.
Click to expand...
When I started looking at EFI in detail for what to do if
It was confusing. The original O2 sensors 4 pin was narrow band (2 heater pins and 2 sense wires) Wide band added extra wires (this are blank AFAIK in the BDM harness and are listed as NC in the schematic on the connector to the EFI). Recent model O2 sensors are now able to be wide band 4 wire from what I have read, but I would suspect need a system designed for 4 wire not 6 wide band sensors.
Confused yet
The truth of the matter is O2 sensors are not required to run, they can and in some efi systems are only used to set the bike up. (workable but less than ideal as the beauty of EFI is constant fine tuning based on current situation.)

I have one very cheap suggestion to try for you that worked for me when I was having trouble.

Go buy a set of E3 spark plugs for that bike and see if that helps. they are maybe $7/ea

Now I know that there are all the naysayers but I am only speaking as to what worked for me.
Several yrs ago I was having a lot of trouble with the bike at 3500 rpm when accelerating hard. Bike would sputter and not respond smoothly.
I was also fouling the champion plugs in 300 miles and having to change them.
While waiting to change the O2 sensor, I decided to try the E3 plug -- Damn thing ran, no sputter, no fouling in 300 miles.

The last TPS i bought was actually the one for an older Harley that worked perfectly, I'll see if I can find the part number in my notes (it's still on the K-9 after several years.)
 
S

Sven

Well-Known Member
TPS is for ignition curves, and bottom end kind of rpm loads. VOES is for heavy loads. The more wires of the 02, the faster type math to the chemical reaction. In other words, think of the definition of magnetism>>> You can't separate heat from the chemical reaction.

Like the evolution of a candle, to a bulb, to the LED. 6 wire might run off the fore and aft cat of both 02's pre-cat sniff, post-cat nip, nice little atmo. So once again, fuckit, go back to electronic curves in a box. Don't need an 02, don't need a TPS, don't need a VOES.

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Jwooky

Jwooky

Well-Known Member
Th EFI parts are all name brand and available. They are all very reliable.

There is truly no reason to change any of them other than the pump and the O2’s. They are in fact wide band, and clean everything else

No disrespect, but you need to find another Mechanic. There is too much guessing and throwing parts at it, without any proper diagnosis.

Did they even check the faults were?
 
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