Changes in Flywheel Weight?

[allanrps]

So I am in the process of updating my bike to a pma charging system, and when removing the stator from the crankshaft I noticed that it is much heavier than the flywheel I plan to put on. My memory thinks it must have been at least twice as heavy. Does anybody have any experience or guesses on how this might affect my bike's performance? I've done my reading on the effects of flywheel weight, and I understand them, but since I have no experience with this I don't know the scale of the effects. I already find this bike prone to stalling, with it's low idle power and very small friction zone, and I'm not so sure I can tolerate it being too much more so. Also, I really like the even throttle response accelerating and decelerating and don't want that to be too negatively affected. Does anybody have any ideas?

Thanks,
Allan

 

[Wolfe_11B]

The rear tire will 'see' more hp most likely. It will rev faster. But you'll lose some stored energy, and you'll probably get a lot more vibration. I took a pound off mine but haven't run it yet so can't say for sure what it will feel like, but from past projects I can guess.

 

[16VGTIDave]

Reducing the mass of the rotating components will, as you know, make the engine easier to stall. It will also rev up or down much faster. And any slight changes in the throttle will be noticed. Engine braking will be stronger.

I put a lightened flywheel and clutch in my street/track VW GTI a decade or so ago. After a few months I stopped driving it on the street. It was too sensitive. The idle shook the entire car, you could feel every power stroke. The engine had to be revved and clutch slipped to get moving or risk stalling, and every bump that caused my foot to nudge the throttle had the engine reacting. Made for a rough ride when trying to hold a steady speed. It was pure hell in town or in stop-and-go traffic. But it was a lot of fun on the track!

 

[allanrps]

Thank you both for your input. Its especially enlightening to hear about your experience with your car Dave. Hopefully the difference isn't quite as dramatic on my bike... There might be some room to add some weight onto the flywheel, I don't know. I'd definitely like to hear about how that flywheel works out for you Wolfe.

 

[xschris]

If you remove the e-starter clutch from the fly wheel that will be almost 2lbs. alone.

 

[allanrps]

I'm not trying to lose weight on the flywheel, I'm just upgrading the charging system, and the flywheel for my new charging system is already substantially lighter than stock. I'm actually hoping it ight be possible to add weight. Doesn't the e-starter clutch not rotate with the flywheel when not under load from the estart motor, and therefore not contribute to the rotating mass? Or do you mean remove the bits inside the rotor?

 

[xschris]

I am talking about the part that bolts to the fly wheel.

 

[allanrps]

Ah I see! Sorry, I forgot that part was bolted on.