You may have a wheel problem due too the fact of too much difference between 26 and 32 inch wheels. It may be advisable to check the gears in the transmission to see if it is slow enough.
I think there would be no problems with working speeds due to the fact that I am working mostly in 2-nd gear during corn harvest (hydro lever in upper part of speed range). In beans combine capacity is mostly for 2 nd. gear, but working in 1 st. gear beacuse of low cutting (manual height lifting_lowering).