Quote:
Originally Posted by HAHA
A heavier flywheel may give you better low end torque.
|
Actually, it won't affect torque at all. Torque is a function of the engine tuning.
Extra flywheel mass may help an engine to run smoother at low speeds, or a lighter one may give quicker acceleration, but it has no effect on the power being produced by the engine.
An engine with very light flywheel mass may have plenty of torque, but if run right at idle it could be prone to stalling if something drags the RPM down just a tiny amount. Put a heavier flywheel on that same engine and you'll find that it will chug along, and the extra mass helps it to ignore any minor changes that would have the light flywheel vehicle stalling. I've noticed that on trials bikes. My Kawasaki vintage trials bike has a fairly light flywheel (for a trials bike) and it may stall if it hits a little bump when running right at idle, where a Bultaco (with a much heavier flywheel) will keep going.
A heavier flywheel may also make the vehicle less prone to slowing down at high speeds if there's a gust of headwind. The flywheel keeps things moving. Some teams will run a heavier crankshaft/flywheel at tracks like Daytona so that gust of headwind doesn't drag the engine down out of the powerband. The Honda 6 cylinder GP bikes of the 1960s had so little flywheel that if the throttle was shut at high RPM when the transmission was in neutral they pretty much just stop running.
cheers,
Michael