Originally Posted by boxerotto
I wonder if the flywheel and crankshaft are balanced together or balanced Independently.
My goal is to reduce the flywheel mass as much as possible by using the post 80's clutch and "flywheel".
Personally, if I rode a pre-'81 model swapping over to a late model clutch would be the first thing I would do to it. Well, that and converting my snowflakes to tubeless. Swapping over to a simplex timing chain would be a close third. The '81 on clutch is light years ahead IMO both in weight AND function. They can easily handle way more than stock power unlike the earlier units. The earlier units have enough trouble holding stock power!
They are balanced independently. They can be balanced as a unit but I see almost no advantage to it.
I have never shortened an input shaft and clutch rod. I have swapped many input shafts. That includes the later cover plate, clutch rod, lever, the whole deal from cable end to clutch. I recommend someone with experience if you swap shafts. Remember that with modifications supposedly most all transmissions interchange but their parts do not. They will fit together and work for a few thousand miles but then you will have a mess on your hands. Don't make the mistake of thinking that the changed helical gear pressure face angle is the angle of the helical. That is the same for both PFA's. The difference is in the shape of each individual tooth and it is hard to see just by looking.