I have this same problem when i get into a field thats over 1 mile long with some minor bumps that i dont even feel it wont gain any speed in 4th or 5th gear i dont know why? I also have the same problem on hills i cant climb in third gear it just dies out i no its no the rear end bearings because i just replaced the (different problem) I need more power but i dont know what to do

 

I finally got it back from the shop!! There were two problems with it. the first one was that the vacuum passage on the side of the carb was cracked at the top. being unable to find this part from the dealer or aftermarket, we "gooped" it, and put a large wiretie around the carb to hold it against the top of the carb. The second problem was a bit harder to find. The large diaphram at the top of the carb had a fine crack in it. It could not be found until the diaphram was completely disassembled, and even then, it had to be stretched to be seen. While we were at it, all fluids were changed, and front u-joints were put in. It is like driving a new machine! More power than it has had since I have owned it. Thanks to all who responded with suggestions!

 

right on me heap of sh&t runs the same way
I will take a look at he problems you found.
I was getting there but parts are an issue.
need to buy a carb (a good one)