Something else you could try:
Try re-adjusting your clutch and chain. Correct clutch adjustment done at the sprocket area, will help. Try different settings on the worm gear set screw / push rod free play. The manual suggests: backing off screw 4 a 1/4 turn, but for me, anything between 1/8 - 1/4 turn would have an impact of the 1st gear selection after a stop. Remember to hold set screw 4 while locking nut 3.
When the chain has too much slack, there were times when it was difficult to find 1st gear after a stop.There must be some slack (1") on the chain to prevent sprocket and oil seal damage.
Extract copied from manual:
1) Loosen the lock-nut 1 and turn the adjuster 2 all the way into the clutch lever assembly
2) Remove the engine sprocket cover.
3) Loosen the lock-nut 3 and turn out the adjusting screw 4 two or three rotations.
4) From that position, slowly turn the adjuster screw 3 in until it stops.
5) Turn the adjuster screw 4 out 1/4 rotation, and tighten the lock-nut 3.
6) Loosen the lock-nuts 5, turn the cable adjuster 6 between 10 - 15 mm (0.4 - 0.6 in) of free play A at the end.
7) Tighten the lock-nuts 5