The
Valve Adjustment Tutorial thread authored by Red2003 is posted as a "sticky" on this forum. This superb tutorial is must reading for anyone wishing to learn more about performing this procedure on single-cylinder Chinese motorcycles. Please refer to this excellent tutorial for the complete details of how to properly perform a valve adjustment.
I took the following photographs to assist fellow owners of the Zongshen Sierra 200 motorcycle who will be performing a valve adjustment for the first time.
The first photograph shows the motorcycle after removing the seat, side plastics and tank plastic. The tank plastic is held in place by four bolts that attach through holes in the right and left air louver brackets. These holes are highlighted with yellow circles in the photograph.
This photograph shows the underside of the tank plastic. The mounting holes are highlighted with black circles.
The next photograph shows the motorcycle after removing the fuel tank and exhaust pipe heat shield.
I found it easier to adjust the valves after I also removed the right air louver bracket. This bracket is attached by two bolts on the frame, circled in yellow in the next photograph. After removing this bracket you can easily remove both valve tappet covers, gaining easy access to the valve adjusting nuts and screws.
Remove the two coin-shaped covers on the left crankcase to reveal the timing mark and the flywheel bolt.
If you follow Red's instructions you should be able to wiggle the rocker arms when the piston is at top dead center (TDC) on the compression stroke. If both rocker arms are too tight to wiggle, you are probably on the exhaust stroke; rotate the flywheel one more revolution in the counter-clockwise direction.
Loosen the valve adjusting nuts with a crescent wrench. Now you can rotate the valve adjusting screws. To rotate the valve adjusting screws I recommend using the tool pictured below, which consists of a number 2 square drive screw inserted into a wire nut. Once again, the details of building and using this tool are contained in the
Valve Adjustment Tutorial thread.
The Sierra 200 Maintenance Manual specifies 0.06-0.08 mm clearance for the intake valve.
The Sierra 200 Maintenance Manual specifies 0.08-0.10 mm clearance for the exhaust valve.
After tightening the adjusting nut and removing the feeler guages, I suggest that you rotate the flywheel two more revolutions and check the valve clearance once again. If everything still checks out you are finished! Replace the valve tappet covers and reassemble the motorcyle.
Spud
