I'm posting this to make it easy for others to find this info. It originated in this thread: http://www.thumpertalk.com/topic/976951-2012-wr450-starting-woes/page-17 Post #326 and #327 on page 17. "Can we get a part number and vendor for a hand held tool that will connect. It appears the black tool that says "yamaha" in red works? How about the special connector cable that will plug into the tool mention above and to the WR's comp ECU connector? " " I got the YAMAHA FUEL INJECTION DIAGNOSTIC TOOL part # 908900318200 from Ebay (http://www.ebay.com/...984.m1497.l2649). Here were no instructions included so I used the procedures I found on this thread. This (and I quote): I used the supplied lead with the red+black clips and the green lug. I connected the clips to the battery and the green lead up to the green connection in the airbox ( middle pin of 3 pin connector). Tester read connecting so I held down the mode button, then turned the bikes power button, next thing you know Diag mode!!! The above worked! It would have been hit or miss figuring out the last part so thanks to those who put it out there! The FI tool read the CO as 0, so I bumped it up to 9. I hit the button and it fired up immediately. It used to take a couple of revolutions to fire, now it was like a half of one. " /********************/ I can now confirm this tool part number, the source, these connection descriptions, and the initialization method ("hold down mode button...") ... is all correct and works. I ordered the same diagnostic device from eBay, and it was delivered from India two weeks later. I had to build a single green wire interface, from a round "push-in" type to a small "blade" type, for the green wire to mate from the tool to the cycle connector. 10 minutes of cutting spare wire and soldering, and it was done, and it worked. I set my CO / Idle to "8", from a baseline reading of "0", which for my cycle I had measured from a gas sniffer at the dealearship to 1.5% CO (a bit lean). So, "8" bumped it up by a small amount. The result is no change in starting (it was never a hard starting cycle to begin with), and no red header glow on idle (which I partially attribute to too lean idle conditions).