Fuel Injection

[Shuriken]

I haven't been through carb hell for a many months. I suppose after bandaging my fingers the next time I'll be ready to try the FI!

I must admit that the CV carbs on the XS are really amazing. Considering the age of the bikes and how the fuel metering works even to this day is amazing.

Ben

[Bill__Woods]

I have been an ASE Certifed Auto mechanic forfor the last 13 years, including my L1 Advanced Engine Performance certification.
Here is my 2 Cents worth.

Fuel injection is a fuel management system, carburetion is calibrated fuel leak.
On my cars i would much rather have a nice reliable fuel injection system (like chryslers), than a carburetor. I would rather have a Quadrajet or a Dualjet Carburator any day over GMs Multec F/I system ( anyone on the list has any 2,8 and 3.1 liter GM injectors go bad?) or GMs troublesome poppet valve Vortec f/i system
On my XS1100 I am very happy with the mikuni CV carbs. just keep them clean and synched. And don't mess with jetting you don't understand (you know who you are!). Leave the stock jets in it, or just up a size or 2 on the mains.

Check this out.
.Linder Technical Services - Jim Linder "the injector guru"

[Bill__Woods]

I have been an ASE Certifed Auto mechanic forfor the last 13 years, including my L1 Advanced Engine Performance certification.
Here is my 2 Cents worth.

Fuel injection is a fuel management system, carburetion is calibrated fuel leak.
On my cars i would much rather have a nice reliable fuel injection system (like chryslers), than a carburetor. I would rather have a Quadrajet or a Dualjet Carburator any day over GMs Multec F/I system ( anyone on the list has any 2,8 and 3.1 liter GM injectors go bad?) or GMs troublesome poppet valve Vortec f/i system
On my XS1100 I am very happy with the mikuni CV carbs. They have proven to be very reliable over the test of time. just keep them clean and synched. And don't mess with jetting you don't understand (you know who you are!). Leave the stock jets in it, or just up a size or 2 on the mains. And they should be much easier to work on on the side of the road than a F/I setup!

Just my 2 cents....

Check this out.
.Linder Technical Services - Jim Linder "the injector guru"

[Shuriken]

Well said Bill. That's one for my quote book ... "calibrated fuel leak."

[ratbyk]

GM TPI

Hi there Jim Woods. I have an 1988 Trans Am GTA that I have owned for years. Like more than 12. Powered by a 350 TPI engine. It has about 240 km on it. Over the years I have replaced one in tank electric fuel pump and a couple of sensors. Other than that I'm very pleased with the engine. No other engine problems, no other fuel problems. It just keeps perking along quite smartly. Kind of like my XS. Both of them just keep on trucking. Both haul ass very well.
Anyway, with all your F1 experience on GM, what should I be looking for or expecting in the future. Love the car. Certainly looks different then present day jelly beans. Love my XS, certainly looks different then present day zip splats.
I definitely agree with you on the Mikuni's on the XS. Keep them clear, synched and doing there fuel leakage thing and all is smiles.
Ken/Sooke
78E Ratbyk
82 FT500 "lilRat"

[Snow]

Throttle response. Mileage. Power. Extreme ease of adjustment. Emissions.

That about sums up why I am doing it.

A Hebrew national all-beef hot-dog is a beautiful thing...but why stop there? Why not load it up with chili and cheese and get what you really want out of life?

[Bill__Woods]

Oops...sorry about the above duplicate post.

Hey Ken/Sooke,
It is Bill Woods, Not Jim Woods. Must have confused me with Jim Linder that i put the link to.

the one thing I can highly recommend for any fuel injected car is having a Motorvac or Snap CarbonClean fue system service. The machine flushs the fuel rail thru the regulator with high pressure for like 10 minutes, which cleans the Inlet screens on the fuel injector itself and the fuel rail. Then you run the car with the machine seeding the fuel cleaner. not only does this clean the inside of the injector and the pintle, but it removes carbon from your combustion chamber and valves. Carbon restricts airflow, and in some cases fuel atomization. If you have 100,000 miles on you car and have a MotorVac or CarbonClean service done, you will feel the improvement while driving. It will make your car run smoother and feel "peppier".
As far as your Trans AM, replace the fuel filter every 15,000 miles or so. That may seem frequent, but it is not -and "F" body GM cars are a pain to put a fuel pump in. I replace GM fuel pumps all the time. Most of the time the filter is restricted and the pump is burnt up. If the filter restricts the pump works Much harder to get fuel to the engine. GM makes the Worst fuel pump in history, OR the Best fuel filter in the world.

[ratbyk]

FI Service

Thank you Bill, that is the exact kind of service recommendations that I was interested in. I have been changing the fuel filter on a regular basis. That restricted fuel flow at the filter causing fuel pump failure makes good sense. I had not thought of that.
I will have to check into having the fuel rail and injectors flushed.
Changing the fuel pump on this model is a pain in the a__. I know if I ever have to do it again I will be cutting a hole in the trunk floor and not pulling the tank. First time around the car was still pretty new and I did not want to hack it up with short cuts.
Thanks for the info.
Ken/Sooke
78E Ratbyk
82 FT500 "lilRat"

[fredintoon]

Am I the only one in step?

Sold my 1988 Olds with 400,000 km on it because the rust was getting noticeable but the FI was still working great with zero maintenance.
But what I'd like on my XS11 is a manifold with just ONE simple carb on it.

[Shappers]

I have put fuel injection on my bike so I'm biased

The bottom line is that people don't really embark on this journey to get better economy or less maintenance on their bikes.

I believe that people do it as it is a technical challenge and a fascinating modification that one can do to their bike. If you love to fiddle with soldering irons, computers, and browse for bargains on ebay then having a fuel injection setup on your bike ticks all the boxes and makes a very interesting hobby.

At the end of the day, ease of maintenance, 50 mpg and a responsive engine are all plus points but the "journey" is a lot of fun as well

[psycoreefer]

I'm interested, maybe after I go back to work and get cought up on bills i'll give it a go. I just want to because it will be a fun project and because I've got a 73 Datsun 240z I want to put MS on when I get it built so the bike is a good experience builder.

[WMarshy]

Sold my 1988 Olds with 400,000 km on it because the rust was getting noticeable but the FI was still working great with zero maintenance.
But what I'd like on my XS11 is a manifold with just ONE simple carb on it.

That would be one huge carb! There is good reason to having 4 carbs on these bikes, the advantage should be evident when you crack that throttle. I just dont think one carb is sufficient for the job. Anyone agree with that?

Im really interested in going to FI, and think it would be way more efficient and reliable than the carbs. You shouldnt have any mechanical problems with a FI. I would think we could all ride our bikes for many years (forever) and never have to replace injectors or fuel pumps if equipped with FI. I have a '96 Cherokee 2.5L 4cyl and it has 180K miles and I seen them go well over 200K with no FI problems. From my race experience FI is the only way to go. Here is a pic of the race car we built this past winter.





We use a MoTeC ECU for that has custom programmable fuel mapping, then dyno tune the engine to match our custom intake/exhaust. That is a F3i Honda 600 sport bike engine makin about 85hp due to our intake restriction being 20mm. If I get the engine out of my bike and fab a jig I would have access to dyno tune and fuel mapping granted I get FI setup! Ive been looking at Optimum Power Technology so our team can use their software to do engine simulations and tune to the highest degree... I guess my point is, fuel injection is the way to go, new or old, I will be doing a FI mod some day. Right not getting through college is first on the list. I can answer any questions you have about our car and fuel system, just ask.

http://www.optimum-power.com/main.htm
http://www.motec.com.au/aboutecu/ecuoverview/

This should sum up why you want a programable ECU...If you can afford it!
"Modern Functionality
These days, aftermarket ECUs not only control injection and ignition timing, but also manage more complex functions like boost control, idle speed control, intercooler spray bars and traction control. Many ECUs provide extra auxiliary outputs that can be used to activate devices such as pumps, fans and even servo motors.

Recent engine development has led to electronic innovations like continuously variable camshaft timing and drive by wire throttle systems. This has created a need for more sensor inputs and auxiliary outputs and a higher processing speed in the ECU.

These advanced installations require several electronic devices on the vehicle to constantly exchange information using very fast communication. Currently, the most efficient method is via a CAN bus (controller area network), consisting of just two wires."

[XS1100 Newbie]

Love your mind

Nice car. I agree with the thoughts you have on FI, but for those of us that don't understand FI enough to work on it, then the carbs are the way to go. Myself, i can fix a carb on the road, but FI, sensors, ECM's, take equipment that would clutter up the baggage. Also you can make temp repairs on carbs to get you to the next town. Maybe on three carbs or less at 20 MPH, but you get there. With FI when you are down, you are down. Tow truck time.

[JustJeff]

One carb

There is only one carb on my XS....

[fredintoon]

That would be one huge carb! There is good reason to having 4 carbs on these bikes, the advantage should be evident when you crack that throttle. I just don't think one carb is sufficient for the job. Anyone agree with that? - - -

Hi Wade,
Nah, 4 carbs on a 4 cylinder engine is just a styling exercise but yeah, it'd have to be a horkin' great big one, kinda like the one on my old Ford V8. Well, not that big, that one fed a 390 cubic inch engine. How about as big as the single S.U. carb on an Ariel Square Four? And think of the maintenance advantages, time to balance? Zero. And look at how big the jets and internal passages would need to be. It'd take a huge chunk of crud to block them up and no more pulling strands from a wire brush, you could poke the jets out with welding wire.