New-not sure where to start with Harley.....very long!

PaulS:

Late 02 started the fuel injection on HD's

Nope. My '97 Road King was injected, and my '01 Ultra is injected.

ah, so if this is a touring bike(i.e. big twin) it must have an ecu at least. Do you know if there's a comm protocol or just wiring?

ah, so if this is a touring bike(i.e. big twin) it must have an ecu at least.

Touring bike vs. sport bike doesn’t matter. Big twin, sporty, or 4 cylinder japanese bike doesn’t matter. If it is injected, there is a computer somewhere firing the injectors at the right time.

Do you know if there’s a comm protocol or just wiring?

There’s more than just wiring. Whether the system uses some open protocol, or not, I do not know. I do know that sometime after the '03s were released, HD changed the type of fuel injection system that they use. The injectors are the same, so it must be the ECM that changed.

PaulS, he said it had a carburetor back in the first post, so he doesn't have access to a data bus to monitor things. This is an old school bike that he wants to fancy up. EFI was an option from around 96 on, but not everyone got it. There were a lot of riders that felt uncomfortable with a machine they couldn't fix on the road. EFI is hard to fix at a freeway rest stop.

Hooch, this project is really cool. I have a Road King Classic and love it. I left carburetors behind because I was sick of having to adjust them when I changed altitude, but I totally understand your desire. Regarding the speedometer, I would use the GPS, more fun, more accurate and cool looking. For the fuel, put a voltage to it and measure the current from low to high levels. This will give you a feel for how much change there is. You can move the float by using a coat hanger wire through the fill cap. Failing that, drain the gas and check empty, then fill it back up to check full. Note though that the tank is non-linear. The position of the float doesn't truly correspond to the amount of gas left because of the shape. You can fill it, drain it into a bucket to see exactly how much it holds, then add back in increments to see what 1 gallon gives you, two gallons, etc. Then work up a table of values from there.

You can measure the voltage with a simple voltage divider. Don't need a shield for this. You want to divide the voltage down to the range an arduino pin can read and then just read it directly and multiply by the proper factor to get the voltage. RPM on a Harley is a bit weird, it gives two pulses for each revolution; the details escape me, but there are a number of sites out there that discuss this in detail. Look for web sites that discuss measuring RPM Harley. I found the details and how to overcome the problems on an old bike of mine that way.

For testing your various ideas, use the serial output. Plug your laptop into the mega(when you get it) and just output what you see in regular text. Things like, "Read 1.2 volts" or "got seven pulses" will give you what your need. Once you have it working, create whatever you want and display it to whatever cool device you use. See, this way you can change the code and reload and reread the data without doing anything special. Once it works like you want, then you can put it on a pretty display. Leave the debug code in though, you'll want that again later.

Think about an oil temperature gauge; you may want that on hot days. Heck, I would install a air pressure sensor in each tire and put the receiver in the faring to tell me when the tires went low. Never did that, and it's really pricey, but it sounds like fun.

One other thing, the pin sockets on an Arduino won't hold up under the vibration. So, just plugging in wires to figure out what to do and where to hook things is ok, but don't trust it long term. Solder this stuff on. I've tried little computers on a motorcycle a couple of times and that was my biggest hurdle. The darn stuff kept working itself loose. I have a cell phone charger on mine that gave me fits until I just gave up and soldered the darn thing in. Haven't had trouble since.

Keep the thread updated on your progress. Inquiring minds want to copy your ideas.

Thanks!! I was hoping to sink it it the electronics epoxy after its all tested. The tank is off and empty, so I'll run the sender high and low to get voltages for it. I have ohm readings but don't think that's gonna be helpful here.

For the record, fuel injection doesn't necessarily scare me, I've tuned several bikes with it, but I couldn't pass up the deal on this bike, and its built like I want it.

I'll definitely keep this updated as I go, I'm sure once it comes time to program this thing I'm gonna be lost. Again...thanks everyone for their input!!

PaulS, he said it had a carburetor back in the first post, so he doesn't have access to a data bus to monitor things.

I know that, but he also said that fuel injection was introduced in late 2002, and that wasn't true. When I commented on that, bil2009 had some questions about how fuel injection was controlled. I was trying to answer them.

This is an old school bike that he wants to fancy up.

A wrecked, but otherwise stock, 2002 is hardly old school.

I have a Road King Classic and love it.

Cool. I've had two shovelheads, a 92 softtail (100,000+ miles when I traded it for the Road King), the 97 Road King (84,000+ when I traded it in), and three Ultra Classics - '01, '03, and '10. The 01 currently has 221,000 miles on it, and I still ride it nearly every day. The '10 is for road trips. The '03 is a dust collector.

I have a cell phone charger on mine that gave me fits until I just gave up and soldered the darn thing in. Haven't had trouble since.

What? Is vibration an issue?

The cell phone charger was one of those plug-in-the-cigarette-lighter things that I stripped and repurposed. I put it in the headlamp nacelle and ran a cable out up to my windshield bag. I put the cell in there and plug it in. I have one of those Garmin 550s that bluetooths (teeths??) to my helmet so I can listen to music (seldom), answer phone calls (even more seldom) or listen to directions to some place I've never been (happens all the time). The stupid little charger kept coming apart in various ways from vibration (I think) until I fastened it firmly into the housing and soldered (not plugged) it to the 12V and ground in there. The classic doesn't have a faring (for those that don't have a clue what we're talking about), it looks like the classic motorcycle. However, I can't take on the entire Harley image, after pulling a grasshopper's leg out of my cheek where it had impaled itself and driving through a swarm of bees, I always wear a helmet. Not because they say it's safer, but to keep the bugs out of my face. I also use a windshield because, when you're riding in snow, it helps keep your jacket zipper from freezing shut.

when you're riding in snow

Brrr, I got off bikes because I couldn't handle the cold in an area that seldom got anywhere near having snow. I don't know how you northern hemisphere guys do it.

I'm back on them now but I have the opposite problem, too hot for leathers.


Rob

Hooch, I have a three page thread dealing with a similar topic for a 1985 Sabre here.

What? Is vibration an issue?

I wasn't sure if that was meant as being humorous seeing as how you own a few. Not to start a flame war, but the vibration factor on that type of V-twin is going to be a lot worse than just about anything else ridden on the street.