Does this exist? Thought I read about this somewhere.

 

Bump...I'd like to know this too

 

If it negatively affected tractability/drivability, I wouldn't want it. My only experience with LWFWs was on a Ducati where I went from a 4 lb flywheel to a 8 oz one (also lost weight with a lighter clutch basket). Throttle became a light switch and caused measurable engine braking off throttle. Truthfully the PDK car slows considerably as is off throttle which tells me the flywheel mass is quite light for the task.

A heavier flywheel would be perhaps more fun as you'd be on the power more and when you lifted the car wouldn't decelerate as rapidly, requiring more downshifting and/or braking.

I miss 2-stroke street bikes (which I grew up riding in the 70s) as they had the character of minimal deceleration off throttle. Opposite of 4-stroke engines of the day.

 

I was going to ask you why you would want it but it doesn't matter. I don't see how it would benefit anything and wonder why anyone would simply seek to spend money on changing something that is already near perfection.