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Fuel/Spark Effect On Engine Braking

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KurtW

Electrical
Joined
Nov 25, 2008
Messages
4
Location
CA
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.
 
well, if you're creating flywheel power then you're absorbing less.
 
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.
 
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.
 
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.
 
I would have thought a throttle return stop would limit engine braking.

Regards
Pat
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