Seeking XB9 ECM Suggestions

[34nineteen]

I'm a carb guy from way back as well IMO the Buell DDFI2-3 fuel injection system is rock solid and still works well, but remember it was designed 20 years ago! It gets a bad rap because of poor motorcycle maintenance, *unqualified modifications, and just being old tech in the time of i-phones now.

Since the ECM was jailbroken and 10,000 rookies got to mess with "tunes" it's been a ****show. Even worse "My bike sat for 5 years and now it runs like crap when I jumped it and went WOT down the street, I need to tune the injection to fix it!". NO dammit... FIX it, THEN tune it. (Sigh)

I can't begin to explain EPA regs for clean running in this post. Simply that it's not "running lean". That would make terrible emissions as well (HC). 95% of the time your bike is running in Closed Loop "part throttle cruise" where the ECM adjusts to keep the mixture perfectly stoic many times a second. Not lean, not rich, and the pipe won't matter because its not at max power. The ECM is adjusting constantly, many times a second, and well within the ECM's adjustment parameters.

In order for an engine to run "clean" it's not about using less gas (remember, lean=bad emissions). It's about:

1) Adding/subtracting gas slowly, so that most of it is burned in the engine and not sent out the tail pipe (bad emissions).
2) Using the minimum about of gas for acceleration (and WOT), so that most of it is burned in the engine and not sent out the tail pipe (bad emissions). Less gas than max power is what "they" mean by 'running lean, EPA BS...' but it isn't technically "lean".

Of course neither of these things is good for rapid engine speed changes or maximum power, so the solution is to change the Open loop fuel map for more gas on acceleration and more gas at WFO. In carb speak, it would be a bigger accelerator pump and bigger power valve. The main jets (Closed loop/cruising) stay the same, and cruising is unaffected. You are looking for an accelerator pump and power valve Map, lol.

*Oversimplification warning!* and I should mention that some believe tuning the Closed Loop targets richer (bigger main jets) help it running. I've pulled out too many black sooty plugs to believe that, and why would you need to add too much gas when you're just cruising?

Hope that helps!

CoOter,

You have been warned about this before. Riders must purchase a special tool to determine this. Its $410.00USD+ship+sales tax.

I will grant you a pass this one time with a firm warning. No funny business or other subterfuge will be tolerated.

34nineteen
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