Oilhead Tech Pages
Oilhead Tech Pages
Ken Krumm - krummk@kansas.net
In September 2001, I installed a Techlusion 83i Power Box (83i) on my 1996 R1100RT, to eliminate lean fuel surging that developed between 3000-4000 RPMs. After 4,000 miles with an 83i installed, I couldn't be happier with the results. However, the installation wasn't totally painless. Hopefully, this article will describe in a relatively painless way, how to install an 83i on an oilhead.
For the purpose of this article, I will describe only the methodology for installing an 83i in the control mode, since this is a more time consuming application. To install an 83i in the stealth mode, follow steps 1 and 2. I will also describe how to fine tune an 83i with a Digital Voltmeter (DVM).
Borrowing from my article in the February's 2002 issue of BMWON, the following information explains what a Techlusion 83i Power Box does to reduce or eliminate lean fuel delivery surging. "Drawing about 25 milliamps of power from the power side of the left fuel injector, the 83i operates by monitoring the triggering sent to the injectors. R1100 series injectors are ground-triggered devices. This means that the injectors have power supplied to them at all times. The Motronic simply turns on an internal transistor at the appropriate time to provide a momentary ground (measured in milliseconds). This causes the current to flow through the injectors, which energizes their solenoid coils, creating the magnetic fields, which lift the injector pintles to let fuel flow. The 83i box simply provides a ground circuit to continue power flow through the injector even after the Motronic has turned its transistor off. Since the 83i is extending the length of time the injector circuit has a ground, it is extending the length of time the pintle is open, therefore increasing the amount of fuel flow."
Paul Glaves wrote in the same issue of BMWON, "The Power Box can be adjusted to extend the pulse width in two regimes: one below the and one above a crossover setting. The crossover point is computed based on the percentage of total time that the injector is on. That crossover setting is adjustable using one of three small screwdriver adjustments on the device. The other two adjustments (center and right) control the length of pulse added, one for below and one for above the crossover point."To setup an 83i in the control mode, you are required to disconnect the 02 Sensor.
The Techlusion web page states, "The Control Mode is just that we default the ECU to a lean fuel map and let the 83i control both the cruise and performance aspects of the fuel curve. On the older bikes typically before 1999 this default map is attained by unplugging the O2 sensor and using the 83i to adjust the fuel curve to your personal preferences. On 1999 and newer bikes the O2 sensor is unplugged, the Cat Code plug is removed and a jumper wire is placed connecting the terminals as shown in the picture of the Cat Code receptacle. Once this is completed, you are in control of the fuel curve using the 83i. The Control Mode is the 83i's normal function mode for all other motorcycles."
To install an 83i in the control mode, follow steps 1-7. To install an 83i in the stealth mode, follow steps 1 & 2. Use the initial setting provided by the installation instructions.
1. Remove the seat, saddlebags and side covers.
2. Remove left and right mirrors and side panels.
3. Disconnect the air intake sensor on top the air cleaner cover, remove air cleaner cover, and remove the black air intake tube to the air cleaner.
1. Disconnect the battery to allow the Motronic to reset at the negative post.
2. Connect the tap connectors
to the left side fuel injector. (See diagrams below)
a. Connect the blue wire to the yellow/white
wire.
b. Connect the red wire to the green/white
wire.
c. Connect the black wire to the battery
ground wire.
Photo Reference: http://www.techlusion.com/OilHeads.htm.
Modification by Ken Krumm
3. Place the 83i fuel module out of the way in preparation for lifting the fuel tank.
1. Carefully remove the fuel tank retaining bolt on the right side of the fuel tank. This bolt is located on the right bottom corner near the battery. Caution: The bolt has a nut on the backside. After loosening, gain positive control of the nut to avoid having it drop into a hard to reach place. Set the nut and bolt aside.
2. Pull the fuel tank slightly rearward and lift up about two inches. If you tilt the tank a bit to the left, it will stay up in that position.
3. Trace the O2 sensor located on the right side of the exhaust system in front of the catalytic converter to the cannon plug under the tank and disconnect the plug. Secure the disconnected cannon plugs in place.
4. Lower the fuel tank and secure the fuel tank retaining bolt. Caution: Ensure your throttle cable on the right side returns properly into its retaining caps. By lifting the fuel tank, the cable may pull out of its seat and not properly reseat. Failure to return the cable to its seat may desynchronize your throttle bodies.
If your bike is a 1999 or older,
use your stock Cat Code Plug. If your bike is newer than a 1999, Techlusion
recommends removing the stock CAT code plug and fabricating a CAT code plug
jumper (see diagram below). After fabricating the jumper, file off the connecter
nubbins and insert into the jumper locations in accordance with photo below.
Photo Reference: http://www.techlusion.com/OilHeads.htm.
Modification by Ken Krumm
1. Open the 83i fuel module box by removing the two cover retaining screws.
2. With a small screwdriver, turn
the left pot fully clockwise to the 11 o'clock position. This allows
the 83i to automatic determine green (center pot) to red (right pot) changeover
based on engine load. In the control mode, this pot will never need a future
adjustment. 
Photo Reference: http://www.techlusion.com/OilHeads.htm.
Modification by Ken Krumm 3. With a small screwdriver, turn the center
and right pots fully counter-clockwise to the 1 o'clock position. This
turns off both midrange and high range pots for the initial startup.
Photo Reference: http://www.techlusion.com/OilHeads.htm.
Modification by Ken Krumm 4. Reconnect the negative battery terminal.
1. Start the bike and warm up to normal operating temperatures (five bars). Note: After restarting with the center and right pots turned off, the bike will initially have a hard time idling without engaging the choke lever. Why? With the 02 sensor disconnected, the Motronic will defaulted to a leaner map then it normally uses.
2. Disengage the choke lever.
With a small screwdriver, slowly turn the midrange center pot until it's between
the 2-3 o'clock position. This will add a small amount of fuel by extending
the opening of the fuel injectors, and the engine will smoothen out. Since
your center pot is your midrange pot, it will affect idle. So, you have two
adjustment options at this point. a. Your first option is you can adjust
the center pot to where your idle returns to your desired idle speed. BMW specification
is 1000 RPMs +150. b. Your second option is you can adjust the center pot
for best performance and readjust your idle with the brass air screws.
Photo Reference: http://www.techlusion.com/OilHeads.htm.
Modification by Ken Krumm
3. With a small screwdriver, slowly
turn the high range right pot until it was between the 2-3 o'clock position.
Since this pot activates in the control mode under load at approximately 4500-5000
RPMs, the motor idle is not affected. This is the performance pot.
Photo Reference: http://www.techlusion.com/OilHeads.htm.
Modification by Ken Krumm
Note: Techlusion does not recommend adjusting the center or right pots beyond the 3 o'clock position. Adjusting this pot past the 3 o'clock position will not damage your motor. This is a point where you've reached maximum performance. Adjusting beyond the 3 o'clock position will waste fuel without a performance return.
1. Above the three pots are three
small test point labeled Z, Y and X. The Z test point is for the left pot,
a Y test point is for the center pot, and the X test point is for the
right pot.
Photo Reference: http://www.techlusion.com/OilHeads.htm.
Modification by Ken Krumm
2. With the bike running, connect
the negative lead of the DVM to a ground or the negative battery post. With
the red positive DVM lead, touch the Y test point. At 1 o'clock (fully counter-clockwise),
the pot is off and your DVM will display 0 volts. At the 3 o'clock position,
the DVM will display approximately 2.50 volts (maximum range for control mode).
Again, more fuel is not always better. Adjust your bike to where it runs best
and is the most fuel-efficient. Each bike is different. I prefer my bike around
2.35 volts. For touring, you can turn down the pot to around 1.50 - 2.00 volts
for maximum fuel efficiency. The center pot is your primary adjustment for
midrange touring or cruising. Note: By securing the negative DVM lead to a
ground, you can adjust the center pot with a small screwdriver while watching
the DVM increase or decrease in voltage.
Photo Reference: http://www.techlusion.com/OilHeads.htm.
Modification by Ken Krumm
3. With the bike running, connect
the negative lead of the DVM to a ground or the negative battery post. With
the red positive DVM lead, touch the X test point. Again, at 1 o'clock (fully
counter-clockwise), the pot is off and your DVM will display 0 volts. However,
at the 3 o'clock position, the DVM will display approximately 1.50 volts (maximum
range for control mode). About 1.0 volt less than the center pot. The right
pot is your high range pot that activates in the control mode under load at
approximately 4500-5000 RPMs. I prefer my bike around .95 to 1.05 volts.
Photo Reference: http://www.techlusion.com/OilHeads.htm.
Modification by Ken Krumm
4. Put the cover back on the 83i fuel module box and secure it to the recommended location by Techlusion (see photo above). Retain in place.
5. Since you moved the throttle cables lifting the fuel tank, I recommend checking the throttle body synchronization before reassembly.
6. Reassembly the bike.Final Notes: If you are fine tuning with a DVM and want to test different settings, I recommend temporarily securing with Velcro the 83i fuel module box to the top of the air cleaner cover for easy adjustment.
Caution: Ensure your bike has adequate space between the air cleaner cover and seat before sitting on the bike to avoid damaging your 83i fuel module box. Since this location has a tendency to collect water during washing with a hose, I don't recommend mounting the 83i fuel module box on the air cleaner cover permanently.
When you have achieve the desired adjustment for the center and right pot, record your voltage for each pot and return the 83i fuel module box to Techlusion's recommended mounting location. During 6,000 and 12,000 mile tune-ups, check the 83i fuel module for proper adjustments.
Ken Krumm
3709 Plymouth Circle
Manhattan, KS 66503
krummk@kansas.net
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