Finally-a fuel injection system that really
works! Pegasus introduces the PFI-V Electronic Fuel Injection
and Ignition Control System!
Not just a replacement ECU but an ENTIRE engine
management system for any V-Twin Engine!!! Kit includes
everything you need for a turn-key system; throttle body, fuel
injectors, ECU, sensors, fuel pump, ignition coils, wiring
harness, and all mounting brackets!
What can electronic engine management do for you? By
combining both electronic fuel injection and ignition control into
a single package, you can expect: much more power, better fuel
economy, crisper throttle response, easier starts, and complete
Here are all the elements to the complete, tightly
organized Pegasus system. We didn’t use all of them due to our
Assalt Weapan, Bonneville Bike configuration.
Key Features Include:
Controls both fuel and
Sequential timed injection
Enhanced fuel atomization
Easy adjustments by rotary switch, PDA, or
Uses automotive sensors-available
Teflon coated, silver alloy wire and
Machined from billet aluminum-
huge 53mm throttle!
Easy to tune-use the spark plug method or use our closed
loop control and dyno tuning!
The PFI-V system is a self-contained engine management
system designed specifically for V-twin motorcycle engines. It is
not a “replacement” brain for a motorcycle already equipped
with fuel injection. There are just too many benefits that you see
when you switch to the PFI system to not consider it, especially
on larger engines! –
PFICOMM is our computer communication program used to
alter the files stored in the PFI brain. It will allow you to modify
parameters as well as maps, store them in a file, load them into
the brain, and save your changes on the fly!
Things to think about prior to installation.
• Poorly installed intake and exhaust manifolds can cause
air leaks, which
can lead to improper air-fuel mixtures and exhaust backfires.
you tighten fasteners to their proper torque ratings.
• Not all air filters are the same! Make sure your air filter
system is free
flowing. A large volume air system acts as a plenum and can
increase useable power. Gooseneck-style intakes actually help
tuning, as the intake manifold is much too short on most
• Most motorcycles are run for short periods of time, then
they sit. Fuel in
a float bowl can get “gummy,” leading to main jet problems.
The same is
true for fuel injection. Make sure you use a gasoline additive in
tank to clean your fuel injectors and fuel filter on a regular
Please make sure your engine is in proper mechanical state
before installing a
PFI system on your bike, as there is no point in trying to tune a
bike with a
mechanical problem. If you feel there might be a problem with
have a mechanic perform a compression test, leak-down test,
plugs, etc. before installing your PFI system.
This is the old stock configuration ignition pick-up
The PFI system consists of two hardware sub-assemblies (1)
(2) Coil assembly. The throttle assembly resembles a carburetor
except it has
the brain mounted on top of it, plus injectors on the bottom and
position sensor (TPS) on the side.
We didn’t use the standard Pegasus top
motormount/coils/fuel pump system and stashed the Fuel Pump
under the seat.
The coil assembly contains the coil, fuel pump,
electrical components, and pressure regulator. There is also a
tooth ignition pickup wheel, which replaces the stock one in the
but we use the stock ignition pickup sensor.
This pickup wheel, with its many
teeth, is the key to sequential fuel injection and single fire
The throttle assembly is designed to attach to an S&S Super
G (53 mm
diameter hole) or equivalent intake manifold. If you do not have
one on your
bike you can purchase one directly from BDL or from S&S, or
from anyone that
makes such a manifold.
We didn’t use the stock Pegasus system, but used
our stationary mounted Dyna Coils.
The coil assembly is already attached to the supplied top
engine motor mount
designed for rigid mounted engines. If you have a bike with a
engine, you can use a special adapter available from BDL.
1. ATTACHING THE THROTTLE ASSEMBLY-Using the
supplied 3/8-16 x
1.25 bolts, attach the throttle assembly to the intake manifold
included insulator block using a light film of silicone sealer.
Note: It is
imperative that you use the supplied bolts as longer ones may
the brain and locktite is recommended.
This air filter backing plate is designed for stock
applications, but I’ll make it work on a basically Shovelhead
2. ATTACHING THE THROTTLE SUPPORT PLATES-Attach the
support plate and your air filter backing plate to the front of the
Connect the filter support plates to the cylinder head breather
the stock breather bolts.
3. ATTACHING THE THROTTLE CABLES-Loosen the throttle
cables at the
throttle grip, then install the barrels at the cable ends in the
Make sure there is enough play in the system to allow the return
It is imperative you use a dual cable system as a single
cable system is not reliable. MAKE SURE THE THROTTLE OPENS
WHEN THE THROTTLE GRIP IS TURNED. In other words, do not
the throttle cables backward.
Mil installing the Pegasus timing wheel.
4. INSTALLING THE IGNITION PICKUP WHEEL-Remove the
pickup dust cover and stock pickup wheel. If you have an
ignition system you must remove it as well. Remove the engine
and rotate the engine until it is at top dead center with the
camshaft key slot
in the position shown. Install the supplied pickup wheel on the
making sure the alignment pin fits securely in the camshaft key
slot. Be sure
to use Loctite or equivalent thread locking compound on the
Throttle assembly installation is complete.
Keyway, not shown, must be oriented at 8 o’clock when
is at TDC. If keyway is at 2 o’clock when TDC mark is visible,
you must rotate
crank one complete revolution.
Pickup wheel installed, set screw positioned in cam keyway
Thread fastening compound must be used on the center bolt.
5. INSTALLING THE COIL ASSEMBLY-On to the coil
YOUR top engine motor mount and ignition coils. Replace it with
coil assembly while making sure to connect the 6-pin
electrical connector between the throttle assembly and the coil
Before removing your coil(s) mark the electrical wire (power wire)
power the coils, as this is the wire that turns on the PFI system.
More on this
High pressure fuel filter.
6. CONNECTING THE FUEL SYSTEM-The PFI kit contains a
mounted on the motor-mount bracket, with three high-
pressure fuel lines and
a special fuel filter. You CANNOT use a low-pressure fuel filter
or stock fuel
lines with this fuel injection system!! The kit comes with a
You can’t see it much, but the special Pegasus
Petcock is on the left. It affords a performance outlet and
completely separate return.
Start by draining the gas from the tank, then remove the old
petcock; install ours. Connect the first fuel line between the
petcock and the
top of the fuel pump.
Here’s a short course in hydraulic brake line fab, using the
finest tools. First the clean cut.
Here’s the order of assembly.
Work this collar over the braid until it’s fully seated. Don’t
This is the master’s tool to lock and press the coupling
These mandrels hold the braided line and collar perfectly
still for pressing.
The operation was underway.
Connect the second fuel line (#3 AN braided line)
between the fuel pump outlet and the fuel rail inlet fitting. Now,
last line (fuel return) from the bottom of the fuel rail to the
sure all the fuel lines are TIGHT!!
This shows the rubber return line to the tank and
the high pressure braided line from the fuel pump.
You can now install the bolts holding the
coil assembly bracket to the engine, as well as the top motor
mount (not shown).
7. BATTERY/SWITCH CONNECTIONS-Now you are ready to
make the rest
of the electrical connections. Note there are only three wires to
battery power (POSITIVE, RED/WHITE), the battery ground
BLACK), and ignition/run power (POSITIVE, RED AND LABELED
These wires MUST be connected DIRECTLY
positive and negative terminals of the battery and the
ignition/run switch and
nowhere else. Do not connect the three-pin connector to the
at this time. Connect the six pin Detuch connector between the
assemblies, then tighten all bolts to the required torque
specifications, as the
motor mount controls the upper vibration of the engine.
8. SPARK PLUG WIRES-We have included special anti-EMI
spark plug wires.....use only these wires. Other wires, especially
do not suppress electromagnetic signals and can interfere with
9. A QUICK TEST-At this point, most of the installation is
complete. If all
wires are connected properly: Flip on the main power switch.
hear the fuel pump “whirr” for four seconds...then turn off. This
as the fuel pump only runs when the engine is running. Now
look at the
brain. The red LED should be on. If not, go to troubleshooting.
10. CONNECTING THE IGNITION PICKUP-If the pump runs
and the red
LED turned on, all is well. Turn off the main switch. It is time to
ignition pickup and set the base timing. First, thread the three
wires of the
supplied ignition pickup through the hole in EVO nose cone.
Press the wires
into the supplied DEUSTCH connector as shown below while
to place wire #1 in position 1, wire #2 in position 2, and wire #3
in position 3.
Refer to the included timing diagram if needed. Then connect
to the mating 3-pin connector on the brain. DO NOT INSTALL
INCORRECTLY AS THIS MAY RESULT A IN DIRECT SHORT!!
11. SETTING THE BASE TIMING-Is the engine still at top
dead center? It has
to be to perform the next step. Install the ignition pickup
loosely. Turn the
pickup COUNTER- CLOCKWISE as far as it can go. Turn the main
on. The green LED on the brain should be on. Now rotate the
CLOCKWISE (slowly) until the green LED on the brain turns off,
rotating the pickup clockwise until it turns on again. The engine
statically timed at 0 DBTC. With a pencil, put a mark on the
degree line on
the pickup and the inside of the cone. Rotate the pickup 10
CLOCKWISE and lock it down (marks are visible on the ignition
plate). The engine is now statically timed. Hardware installation
12. BLEEDING THE FUEL PUMP-The fuel pump may have air
at this point
and will require bleeding. This is accomplished by loosening the
line on the fuel rail and turning on the ignition switch. The
pump will run
and force air out. When done properly, the fuel pump will rotate
with a high
pitched “whirring” sound.
13. THE FINAL TEST-Now you are ready to start the engine!
Turn off the
ignition switch, then turn it on again after 5 seconds. The red
LED will turn
on. The green LED may or may not turn on, depending on the
the engine. You should hear the fuel pump whir, then stop.
throttle grip to 45 degrees with your hand, and you should hear
“clicking.” This feature, which is used to prime the engine,
injectors are functioning properly. Only leave the throttle in this
around 2 seconds, then return it back to zero. Now depress the
button, just as you would normally to start the bike. You should
here it fire
or even possibly start. If so, turn off the engine and perform a
system check to verify there are no fuel or electrical problems.
14. MAKING PFI WORK FOR YOU-Since the PFI system was
work on any V twin engine, you must load the proper file into
before testing the bike. If you are capable of doing this, proceed
to section 6
to install the proper map file.
The PFI kit comes with a base map for an 80 cubic inch
engine with an
Andrews EV-46 cam and a Supertrap. If you have any engine
other than this, you must load the proper map into the brain.
This can be done
either with a PDA or with a computer. We are assuming you
PFICOMM onto your computer. If you haven’t you must have a
running Windows® 98, or 2000 and a CD-ROM drive. Run the
to install PFICOMM our communications software.
1. Take the supplied electrical communication cable and
place the RJ45
connector into the receptacle on the brain. Connect the other
side to the
computer serial port. If you want to use your PDA instead of a
computer, you must use the PDA-brain cable/software available
2. Again, assuming you have installed the PFI
supplied in the kit on your computer, start the PFI
then turn on your system using the main switch. When
prompted to load all
brain info into your computer, reply “yes.” You can examine the
the brain directly, but don’t change anything at this time!
3. Because the PFI system was designed to be used on any V
twin motor, the
proper files that most closely fit YOUR motor must be loaded
into the brain.
Under the main menu, select “file” then “open.” Find a file that
matches your configuration. Then, again under “file” select
“send file to
ecu” and send. After a couple of okays and prompts, the file will
into your brain (ECU). Software installation is complete!
The two mad scientist behind the Pegasus marvel, Mil Blair
on the left and Dr. Stew on the right, a professor of mechanical
engineering and Cal State Northridge University.
TIME TO CRANK IT UP
At this point, the setup is pretty much complete. You have
mechanical part of the installation as well as getting the proper
maps into the
brain. The PFI system responds very similar to a carburetor in
starting/running....just better. However, it is important to
nature of the PFI system and just how it responds to your inputs.
Again, if you have downloaded a map that is perfect for
configuration, then you will be able to crank it up, and ride
away! But the PFI
system is just so powerful, you’ll want to take a crack at tuning
even if it means just turning the knob on the brain. Remember
main jets and getting gas on your hands (and searching for the
dropped)? Those days are over.
Starting Your Engine
The PFI system does not have an automatic choke and extra fuel
introduced manually when the engine is cold or below operating
This is accomplished by turning the knob on top of the brain to
the “C” or choke
position prior to starting. Please note the amount of extra fuel
can be altered (see tuning section).
You may also want to add “primer” fuel to the engine before
you start it.
Assuming the main switch is on and the fuel pump has stopped,
by turning the
throttle past the 1⁄2 point an extra spray of fuel will be
introduced into the intake
manifold (BE CAREFUL!! Leaving the throttle open for too long
engine off may flood the system). A couple of quick squirts will
do the trick, and
it’s usually only needed when cold.
With the throttle completely closed, engage the starter
button. The engine must
turn over at least two times. Slowly open the throttle until the
Then let it idle at 1500 RPM until it warms up. When warm, turn
the fuel knob
back to the “normal” position.
Running Your Engine
With the fuel knob in the “normal” position, run the bike as you
would. Check for throttle response crispness by first rolling on
the throttle, then
increasing the roll rate. Note that throttle crispness can be
changed (see tuning).
In high gear, roll into the throttle and put the engine under load
to see if it
responds. Decelerate and listen for backfires.
You can use the spark plug method to see if the engine is
running properly. In
high gear, roll on the throttle and put the engine under load up
to 5000 rpm,
then pull in the clutch and kill the engine. Coast to a stop and
check the plugs.
If the bike ran great but the plugs seem white, do not be
Fuel Injection systems have better fuel atomization and don’t
need as much fuel
to achieve power, but it you felt a “flat” spot, note the rpm at
occurred...you can fix this with a PDA or laptop. On the other
hand, if the
plugs appear to be sooty black, the fuel mixture is too rich.
You can then adjust
the internal fuel map using a computer, PDA, or you can use the
knob on top of
the brain to lean the mixture. By rotating the knob counter
“L” you can lean the mixture in 5% increments. Try one click and
spark plug test. Note that you can also richen the mixture at
any time by
rotating the knob clockwise towards “R” to richen the mixture as
well, in 5%
The famous Pegasus tuning chef.
Do you want to get good fuel economy on the open road?
When up to cruising
speed, turn the mixture knob counter clockwise towards lean
increment at a time) to increase your gas mileage. You won’t
have much power
and you must be careful not to accelerate hard under this lean
condition as you
might damage your engine. Don’t forget to turn the knob back
to the normal
position when you’re done.
Watch for more on the Pegasus Nitrous controller in the near
Call us at: (714) 398-2360
Email us: email@example.com