My rides doin the same thing,Itll be in first or 2nd gear and it feels like 5th for a couple seconds then it kicks back in after it jerks.
First thing i thought of was Fuel system.
Im replacing my Fuel filter and pump,im thinkin its getting choked off.
Also a burnt clutch would grind.
Im having to replace my throw out bearing and my 2nd gear synchronizer.