WR450F 12+ (EFI) Gas Tank any recommendations?

I think Chu is talking about the ignition timing, not the fueling.

I would think if the spark comes later the fuel might not burn as completely.  Maybe you could cut some fuel where there's negative timing numbers.

I think Chu is talking about the ignition timing, not the fueling.

Damn, yor're right :facepalm:


My bad, I stand corrected, sorry chu, you are correct, :thumbsup:

shifting the spark way back towards "late" (negative PowerTuner numbers)  will lessen efficiency.


It was very interesting to witness back when my buddy's WR426F CDI had the microcontroller die

(no spark advance anymore) but the fallback startup circuitry still alive:

The bike would fire up a readily as ever, you could ride it at walking speed

but any decent throttle opening would be of no effect. :banghead:


The engine did ignite every combustion cycle nicely, no backfiring, stalling or surging,

but it did make absolutely no usable power. It does take really long to ride home with 15 mph :ride:


Our reasoning was the ignition did fire at the kickstart timing, w/o ever advancing.

Ingesting a suitable amount of fuel and igniting it very late, w/o producing adaequate power must indeed be very inefficient.

Edited by WRF-Rowdy

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now