Look ma: no carbs!

Just wanted to share a bit about my recent conversion of my '82 SECA 750 to fuel injection. It still needs to have its ignition and VE maps dyno tuned, and I've got some tweaking to do for startup/warmup, but it's ridable and doing well.

Finally got rid of those #$^% Hitachis!

In case you're curious, the ECU is MicroSquirt, the fuel rail and injectors are from a '99 Hyundai Accent, the throttle body is from a '97 Ford Escort, the coils are from a '95 Saturn SC, and the fuel pump is a Bosch, marked SAAB, that's theoretically the same as those used on Harley Road Kings.

I fabricated a new ignition reluctor, but am still using the stock VR pickups.

The intake manifold I fabbed from copper pipe fittings, 1/4" copper plate, and 1/2" aluminum plate for the adaptor.

Other parts include a new 4-wire Bosch O2 sensor and a new coolant sensor (meant for I don't know what vehicle) mounted in the oil pan.







Cheers,
Paul

 

Holy crap! 8O

That's pretty cool. I'm impressed.

 

NICE!!! I'm sure you could sell numerous kits on this site alone, once you've fine tuned it!

Good Work !!!

 

I've been wondering if you were going to post that here. I've been watching your bike on the microsquirt forum, but I didn't see anymore updates.

How has going to a single throttle body affected the engine?

 

As soon as I saw this my jaw just dropped. I heard of people buying fuel injected systems from other bikes and fabing them up but I must say great job. My props to you sir

 

This site never ceases to amaze me.
It all looks very nice.
It looks like a thoughtful and careful build.
I hope it performs beyond your expectations and provides faultless Injection and performance.

I'm with those who believe that there is a market for the Fuel Injection conversion to these bikes getting rid of the finicky Hitachi's that are so difficult to bring in to maximum performance.

 

Thanks for all the feedback.

Once the dyno tuning is done (should be end of the month) I'll put together a success story on the MS forums along with more of the details, lessons learned, etc.

Personally, even as things stand now, I don't see any issue with the single throttle body. The bike pulls fine and has pretty good throttle response. I went with a single TB for a couple of reasons: one was easy availability from a local scrapyard, the other was that the TB includes an idle air valve, which I think will be important in achieving the kind of drivability I want; hooking one in with a quad TB bank would have been pretty complicated.

 

Thats pretty neat! I too think that would be cool to mass produce and sell. A video on youtube would be cool with the engine running so I can hear it

 

you are Da man! Way to go. no more carbs to sync.

 

How is the electrical system handeling the drain? Is there enough juice to keep it all running with all the lights?

 

Man, that's awesome.

I'd love to do that to my 550. Mikunis aren't as finiky as Hitachis, but every time I ride my R6 I wish the Seca was that trouble-free and responsive.

If you wouldn't mind, once you get it all tuned, I'd really like to take a look at it in person. I grew up in the Springs and live up near Boulder now.

 

i love this stuff! very clean install, interested to see how it changed the power/mileage

 

That is a cool setup, how much of an increase in mileage do you think it will get?

 

Good question about the electrical system. That is the thing that most worried me, especially since I couldn't see any easy way to upgrade the alternator on this engine.

I was most concerned about the fuel pump. I would have liked to have found a good source for a Delphi, as they make some pumps specificly designed for small engines which draw less than 1.5A. I ended up settling for a Bosch (on eBay) that was advertised as being for a Harley Road King. It's actually marked SAAB, though, and, AFAIK, SAAB doesn't OEM for Harley. This fuel pump draws 4.4A when running. It was just small enough to install in the tank through the access cutout for the fuel level sensor.

The new coils probably draw a bit less than the old ones, since they are being properly dwelled by a more intelligent control system. The injectors probably average 1 to 1.5A of draw total. I don't know how much power the oxygen sensor takes, but the ECU itself draws less than 2A.

The end result is that the system actually loses a little bit of charge at idle, but starts charging the battery at about 2K RPM... keeping it charged well enough when riding. I certainly don't have any extra capacity, but I don't really need any either.

If I have any problems with it down the road I may try harder to get a Delphi pump. Someone on the MicroSquirt forum suggested the Honda Rincon pump as being a good choice and apparently not too expensive or difficult to find. During my initial searching the only true motorcycle pump I could find new was an aftermarket one made for Harleys, but that was $500! I also found a source for Aprilla scooter pumps, but I believe those are meant for running a single direct injector, so, higher pressure and lower flow than I need.

Anyone have any tweaks for the stock alternator?

For the fuel economy, I don't know. Currently I'm getting about 40mpg, but there's a lot of tuning to do and the plugs show that I'm running rich through most of my range.

 

I'm heading out the door right now, but I think you can have the alternator rewound for more output. Anyone know anything about that? I'll have to look into it.

 

while searching for oem bits for my xj i stumbled across a few sites that sell upgraded windings for our bikes, might be worth your time to google and see what comes out of it.
once you have it all finalised i would be more than interested in knowing the performance gains and fuel economy you have achieved.
if you decide to go into production i think you will have a big selling item on your hands. trucker

 

SQL, I got to the XJChat page before I got here. Question answered! And way good on you! I would love to convert, not because the Hitachis are a problem for me (they arent) but in terms of efficiency and reduced maintenance.

 

What a fantastic piece of work you have done. I have thought about doing something like this for the longest time but I have so many other things to do I couldn't even begin to start it. It really would be nice to have an off the shelf solution but I think what you have done is way more fun and when I say fun I really mean frustrating.

How much $$$ do you think you're in to this project?

 

It's probably about $1000. If I were to do it again, though, it would be cheaper. That $1000 includes a fair number of junk yard parts I ended up not using and also some tools I wouldn't need to buy twice.

I still also need to spend another $225 on dyno tuning. This is another thing I could have done differently: I could have instead bought a wideband O2 sensor, for about the same money, and used it to autotune the bike.

Biggest expenditures are:

MicroSquirt ECU - $400

Fuel pump - $100 (for a do-over I'd probably pull a Hyundai pump from the yard for $20 or so)

Copper pipe, copper plate, and aluminum plate - $80

O2 sensor - $60

Fuel rail and injectors - $35 (another thing I'd do differently if I were to do this again; I'd instead try the fuel rail and injectors from a Suzuki Esteem - this looks to be a perfect fit, and the rail is much shorter than the Hyundai Accent one I used)

Coils - $25?

Oil temp sensor - $15

Throttle cable - $15

Throtte body with IAC - $10

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Add to that things like:

Timing light - $40

Fuel pressure gauge - $40

Two other throttle bodies I didn't use - $20

An extra fuel rail and injectors picked up for troubleshooting - $35

etc, etc, etc.....

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it would be a long drive but I've got a dyno.