We have about 1 acre at the far end of our town property that is rough and I don't mow it often. But, when I do mow I use one of the foot draggers because they are just so tough. I decided to give the sickle mower a try this time as the growth was a little out of hand.  I knew to use the small mid pto pulley and 1/2 throttle or less. My Allis-Chalmers Early B-10 will throttle way down and I enjoy listening to the 23d engine operate as slow revolutions. I should have taken a picture of the 12" growth but, if you look closely you can see the thick cutting on the ground.  The Simplicity cable lift sickle operated flawlessly at 1/3 throttle in both 1st gear when I needed extra caution, and 2nd gear in the open areas. This is an after picture 

As I finished I felt extra vibration and found one of the heim joints on the pitman to be really worn. When you consider the revolutions and speed these machines operate, there is no doubt there will be wear points.  

Not sure how it held together till I finished actually.

McMaster Carr to the rescue! I measured and ordered the part one day and took delivery the next day. That is service! 

Heim joint installed and ready for the next mow.