Dave Moss on the CALmoto / Motolab / EC997 dyno project

Triumph 675 Daytona
06-12

Initial testing with Factory Pro Advance kit

Motolab in Redwood City, Ca. has done initial testing with using +4 ignition timing on the 600 Daytona. The Daytona has a stock engine, a pc3usb, tuned to Best Power on an EC997 Eddy Current dyno (not on a dj dyno, tuned to an a/f ratio).
Initial results show a substantial hp advantage after adding the +4 advance.

Track testing verifies the aprox. ~3-4 True HP improvement. Before - the rider could barely stay in draft of 750's, now he can easily stay in draft and stay close enough to "show a wheel". That's 3-4 True hp difference.

Tune optimized on our EC997 eddy current dynamometer with digital four-gas analyzer. This is TRUE HP Scale - not dynojet scale!!

Tuning to an a/f ratio will probably not provide proper fuel or ignition metering information. The possible reason why the ignition timing is so far off in the first place is that Keihin, who supplied the fuel injection system to Triumph, "tunes to an a/f ratio" in, at least, the USA. That's why Sudco bought a dyno that "tunes to an a/f ratio" - because Keihin "tuned to an a/f ratio" and Keihin suggested that they do so, too.

Well..... over the years, you can follow the mistaken path of "tuning to an a/f ratio" and Keihin, what they probably did, how they arrived there and the poor results results - and the tuning fixes.

On the Kawasaki carbureted zxr's, like the zx6r in 95-97, to most of the years of zx9's - Both of those bikes were super rich at high rpm, as delivered from Kaw.
If you were tuning, starting from scratch with blank ignition mapping, and looked simply at residual oxygen in the exhaust, you could def. end up making "a/f ratio" numbers look "right" AND be super rich at redline, while being OK at 9000 rpm.  That can happen if the ignition timing is retarded from Best Power degree setting. If the timing is retarded from what's required to fully burn the mixture, the exhaust valve will open and a quantity of unburned hydrocarbons and free oxygen (O2) will get punted out into the exhaust system, where our devious friend, the O2 sensor lives. The O2 sensor dutifully produces a voltage that indicates that there is extra oxygen in the exhaust - and the tuner obediently adds more fuel to make the amount of oxygen meet the preconceived notion of the "right" "a/f ratio. (groan......)

The real reason why there was a lot of oxygen left in the exhaust was because the ignition was retarded from Best Power. Both the 600 and 900 were between 5 and 6 degrees retarded as delivered. That's simply a huge tuning error. The 600, with correct ignition timing, gained 3-4 True, loaded hp and the 900's, generally 5-6 True, loaded hp.

Looking at a 4 gas exhaust gas analyzer's data, rather than a simple so-called "wideband" O2 sensor would have indicated that the ignition timing was too far retarded and Kawasaki - but - the point is that you can and probably will leave oodles of power lost in unknown tuning land if you use an o2 sensor and "tune to an a/f ratio", rather than a real 4 Gas EGA an Steady State tuning.

How Keihin FCR carbs came to be so rich, as delivered "prejetted" for an application, is a whole other story........ That's an O2 sensor saga and fuel delivery state and the o2 sensor errors of a whole new kind crop up...

Now that I've insulted all the engineers in 2 large Japanese companies........ (cringe)

They could just hire me..........

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