VL flywheel truing question

[Buster]

Trying to true set of VL flywheels. I have new shafts,crank pin, and keys. When i install shafts into each side wheel and tighten to around 50-60 lbs pinion shaft is out .0025-.003 and sprocket shaft is out .001. How close a tolerance is acceptable or typical on these old wheels at shafts. I have ground the tapers lightly with old original shafts, cleaned throughly, and using new keys. How can shafts be further trued. I saw in web photos of person hitting end of shaft at taper with lead hammer, but looks like this would damage shaft. Also, according to dimensions posted in Steve Solcombe book, my flywheels are 1931 and later, however there is no timing mark. Is no timing mark common on 1931 and later wheels. Thanks!!

[T. Cotten]

Buster!

Do you mean that when the shafts are between centers, the flywheel has run-out?
Certainly the shaft remains true to itself..

Please note that flywheels that have seen extended service often bulge not only on their circumference, but on their sides, adjacent to the crankpin.
This is normal.
(Indian 101 example shown, ground slightly on emery to display the bulge.)

Please true the shaft to the best average of the flywheel's side opposite of the crankpin.
I often used anvils that supported the pin, while I applied judicious force to the flywheel. But beware cast flywheels can be very brittle.

Often tapers can be corrected by extensive lapping as described at http://virtualindian.org/10techfly.htm.

Good luck,

.....Cotten

[Buster]

Cotten!
The shafts are true. I put one shaft and flywheel into truing fixture on centers. Measurement of runout taken at machined surface of flywheel adjacent to shaft. When you put shaft on anvil, which part of shaft contacts anvil. Do you place any thing between anvil and shaft where they contact each other. Trying not to scar shaft beyond use. You then strike outer edge of flywheel with lead hammer, correct? Is lapping as you described necessary for shaft .0025-.003 out or is it possibly fixable using anvil and mallet method? Thanks!!

[T. Cotten]

Buster!

Frankly, if if you are indicating off of the side of the flywheel, a few thou is normal, and yours don't sound that bad at all; Please remember that only the run-out on the mains when both wheels are assembled is critical.
Strangely, they often true up better as a pair than either one alone.

In the VI lapping discussion, I note that you can actually see a bad wheel wobble, and when it straightens out, its as good as it gets.
The strange aspect is that the lapping procedure never seemed to sink the tapers deeper at all.

My anvils were crude, but usually used a long collar very closely fitted to the shaft diameter, such as a Caterpillar drill guide, or even aluminum billet, welded to a base like a modern rear wheel sprocket.
And I preferred a babbit hammer, but often used a screw-press to be more gentle. Something about the shock of a hammer seems to make things spring back where you don't want them.

....Cotten