Logger4Life
Good luck on your quest for a good 681 crankshaft. I am not sure that they ever built a good one. I have seen 6 of the 681's that broke the crank. The first two that I had seen had port work done and ran the 272 Husky coils. I assume that the crank couldn't take the higher rpms. The next 4 that broke were on bone stock 681's.
Solo has been good about it. When I get one with a bad crank they replace the whole saw, no age limit. I have to send them the complete old saw for replacement. They will then replace the 681 with a new 675 as they have no 681's left.
If you still want the longer stroke of the 681, I would suggest sending out your Dolmar crank and have it stroked.
Later
Dan