Fuel/Spark Effect On Engine Braking

[KurtW]

Just wondering the effects of fueling and spark on engine braking. In my limited experience I have found that more fuel, less timing minimizes engine braking. It also seems to smooth the transition from off-throttle to on-throttle.


I'm talking about high rpm motors (12-15k) and ECU without decel fuel cut.

Thanks in advance.

 

[ivymike]

well, if you're creating flywheel power then you're absorbing less.

 

[KurtW]

Thanks for the reply.

Is there a reason that the OEM has 50-70 degrees of timing in these areas? My thought was the advanced timing was to increase the volume of gas before TDC to increase engine braking.

 

[Lou Scannon]

Nothing technical stopping the employment of negative work for engine braking if that's what's desired. Seems less wasteful to employ fuel cutoff/open throttle engine braking or just let the brakes do their job.

 

[KurtW]

My goal is to have as little engine braking as possible, I have installed a back torque limiter (slipper) clutch on the bike (Aprilia SXV). Engine braking isn't a big deal on tarmac, however riding in the dirt with slicks does get a bit hairy.

 

[patprimmer]

I would have thought a throttle return stop would limit engine braking.

Regards
Pat
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