Thunderbike Engineering

Fitting Instructions
Bonneville/Twin - Air Injection Removal Kit (EFI Models)

Please Note: Read all these instructions before starting - there's more than one way to skin this cat!
  1. Remove seat bolts and remove the seat. (5mm allen key)
  2. Remove the negative wire from the battery's negative terminal.
  3. Lift rear of tank (8mm socket) Remove fuel hose from under tank by sliding the orange sleeve to the side then compressing the tabs in the gap uncovered then sliding the hose off. Don't force it. On the left hand side disconnect the fuel pump connector. On the right hand side remove the breather hose. Remove the tank.
  4. Disconnect the hose running into the airbox and blank the hole in the airbox with the supplied plug. A little RTV silicon will ensure an air tight seal.
  5. Disconnect the hoses to the air injectors.
  6. Remove the air injectors with a 13mm deep well socket or dog leg ring spanner.
      Note: It's a tight fit with minimal clearance so you may need to modify a tool to suit. If the injector is difficult to remove BE PATIENT. Try soaking the base of the injector with penetrating oil.
  7. Install the stainless steel AI Bolts using the supplied copper washers. Torque to 15-20 ft/lbs or "snug" if no torque wrench is available. DO NOT OVERTIGHTEN. Note: Place a couple drops of anti-seize on the threads as this will aid in the removal later if necessary.

    At this point you have 3 choices:
    1. Disconnect air valve (the silver one) and hoses and leave the air solenoid (the black one) connected to the wiring loom. You will need to cable tie the solenoid in place on its spigots once all the hoses have been removed. This option is the easiest if you don’t want to get into engine management software or additional wiring.
    2. Disconnect the air solenoid from the wiring loom. Remove the air valve, solenoid and bracket from the frame. (8mm socket, T25 torx bit) Replace the solenoid with a suitable sized resistor. Use the cable guide to hold the resistor mod in place. This option is tidy and negates any engine management software needs but is a bit of extra work for not much advantage over leaving the solenoid connected.
    3. Disconnect the air solenoid from the wiring loom. Remove the air valve, solenoid and bracket from the frame. (8mm socket, T25 torx bit) Use the cable guide to hold the now redundant solenoid connector. Tape the open connector end to avoid dirt ingress incase of future use. Use the free TuneECU software to disable the SAI and extinguish the check lamp on your instruments caused by the missing resistance of the solenoid. This is the best option for the purist if you want all the unnecessary gubbins gone.
  8. Re-install the fuel tank and re-connect the hoses and fuel pump connector.
  9. Re-connect the battery negative terminal. Job done for options A & B!
  10. For options A and B - replace the seat and relax, job done! For Option C skip this and continue:
  11. Download TuneECU and install it on a computer that can be operated close to your bike.
  12. Buy a suitable diagnostic cable.
  13. Disconnect the headlamp and connect battery to a suitable battery charger. Note: if you decide not to disconnect your headlamp you will need a charger capable of delivering a constant 12-15A during the operation. Small trickle chargers like Optimates will not suffice. With the headlamp disconnected and a good condition battery a trickle charger may suffice but keep an eye on your battery state at all times. Connecting via a separate leisure/truck/car battery is a good idea.
  14. Connect the cable to the bike and computer and start TuneECU.
  15. Turn on ignition.
  16. In TuneECU select Menu > ECU > Read Map
  17. Wait… It will take some time for TuneECU to read the map from your ECU. BING… Map read.
  18. Select Menu > File > Save Map File. Now Repeat this and give your map a new name eg add nosai to the tune number. You should now have 2 map files. Both containing the original file but with different file names.
  19. At the bottom left hand side of the TuneECU screen find the menu + Devices section and uncheck the SAI check box (ie no tick in the box next to SAI)
  20. Select Menu > File > Save Map File to save the change. Now you have 2 map files. One with the original map and one with the SAI checkbox unticked.
  21. Select Menu > ECU > Download
  22. Wait… BING Download complete.
  23. Select Menu > ECU > Erase Error Codes
  24. Go to the diagnostics screen (tabs at top right) and double check for error codes.
  25. All good? Select Menu > ECU > Disconnect
  26. Switch off ignition and disconnect the cable.
  27. Replace the headlamp and disconnect charger, replace the seat and relax, job done!
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