ECU Harness
As part of this build I created a separate ECU harness from the main harness. The goal was to leave a clean pathway to a full race harness—one that omits tail lights, turn signals, headlights, etc. This harness will still need minor surgery for a race-only bike because the ECU and main harness share a few signals for the street features I wanted.
This ECU harness plugs straight into the FuelTech FT550 and handles every sensor, injector, and ignition coil. Revision 1 is 100 % functional; only a few MAP-file tweaks are needed so the ECU reads the inputs correctly.
Thoughts on Construction
FT550 A & B Unterminated Harnesses
I bought FuelTech’s FT550 A & B, WB Nano Pro LSU 4.9, and SparkPRO-2 unterminated harnesses. Every wire is numbered along its entire length—huge time-saver, no chasing same-color wires. I wish FuelTech advertised that; I almost skipped the pre-made harness. Buy it. Just order spare cavity plugs for any wire you pull out on the ecu connectors.
Downside: one end is pre-crimped. When I spliced the gray ignition signals into the SparkPRO-2 harness I ended up with a fat loop. Fix: buy a second SparkPRO-2 connector, cut the factory one off, splice clean, crimp, done.
SparkPRO-2 Unterminated Harness
Skip it next time. The gray signal wires have to be spliced anyway, and the power wires are massively oversized (not TXL, definitely not Tefzel). I cut the connector off, re-ran TXL, and the harness lost 30 % bulk.
WB NanoPRO LSU 4.9 Harness
FuelTech only sells a 10 ft version—ridiculous on a bike. Both ends are pre-terminated with a proprietary 12-pin Nano connector on one end, and the LSU 4.9 on the other. (The power and ground wires are seperate to the oxygen sensor wires though, and are un terminated) Depinning the nano connector is possible but the terminals are fragile; At least I spent two hours on four wires. I bought a second connector kit for the oxygen sensor, shortened the shielded wire down and put the new LSU 4.9 connector on the end. FuelTech: If you hear me. PLEASE publish the connector part number or sell just the connector and pins!!!!
General Notes
The rest was straightforward. Every connector I could source is listed in the PDFs below. The plugs for the ecu connectors are Tyco/AMP Superseal 1.0 Series 4-1437284-3
Reference Documents
ECU Harness Gallery
Photos may show early routing; diagrams are final.
