Here is the problem, 5 speed tranny worked fine until I changed final drives from 4.25 to 4.9. We also put in new 1/2 and 3/4 forks, new syncro's on all gears. First time had problem going into third gear it would act like it wa in but when you released clutch it was not there and needed to be bumped into 3rd again for it to stay. This was only under race conditions. We tore down tranny again and did not find any issues. We installed new shift rod which tightened the complete system up. It nows seems to shift harder even considering the friction of new shift rod. Only raced 6 laps before engine failure but still had problem from 5th to 4th not getting in gear and even third was difficult. I am at a loss as to what the problem could be. Any thoughts?