I owned an old Gravely for a while back when I was doing the small holder dirt farmer/earth mother thing on an off-shore island. The thing was a bit of an orphan as it had too high a final drive ratio to seriously work properly for plowing. Some town councils here used Gravely tractors connected to a largish utility trailer for park maintenance and the like and I think I must've got some town council's reject. It certainly was cheap which should've told me something.
Eventually a neighbour heard on the island grapevine that I owned the Gravely and made me an offer. I was fed up with the thing by this time so I was glad to see it gone. After loading up the Gravely on his old truck he gave me the standard, 'You women don't know anything about how to operate machinery properly' speech. For my part I held my tongue and hid my grin because I knew that he wasn't going to have anymore success than me.
And I was right because that old Gravely did the rounds of nearly all the other other small holders like me I knew. It was taken to bits and put back together several times and various local 'experts' tinkered with it, but nobody had anymore luck with it than I did. It certainly ran well though and that big 'T' head engine was very seriously well made, but as I said it had the wrong final drive ratio for crop work. At the time it didn't cross my mind to put the engine in a bike frame, - I even had a couple of spare Matchless motorcycle gearboxes and clutches stashed away in the old bus I used as a storage shed, - so I suppose it wouldn't have been difficult to do. BUT with two wee kiddies and a partner who was in crisis most of the time with Bi-polar Disorder I didn't really have the time anyway.