How does cam timing affect cylinder pressure?
Effects of Changing the Cam Timing A camshaft that is advanced four degrees will cause each opening and closing event to occur four degrees of rotation sooner than before. This changes the cylinder’s ability to build pressure.
What is the valve clearance on a Honda V4 Cam?
Part number is 07979-MK30000, name is “V4 tappet adjust”. The service bulletin issued with this tool recommends valve clearance of .006 inches instead of .005 that the Sabre/Magna originally specified, as well as use of premium motorcycle oil, changed frequently, and avoidance of prolonged idling.
Why did my Honda V4 cam engine wear out?
Now, the history of the problem. Most of these engines, especially those driven hard, wore out cam lobes, rocker faces, and cam bearing surfaces prematurely. This was especially common in Europe where the bikes are driven harder and faster.
What was the difference between 1986 and 1987 Honda V4 cams?
There is at least one notable design difference mentioned below. The ’86-87 VFR700/750 Interceptors and the 1990+ VFR 750s (with single sided swingarm, no longer called Interceptor) are not affected because significant valve train and oil system redesign accompanied the gear driven cams.
When does the exhaust valve open on a cam?
Since the camshaft turns at half of the speed of the crank, the power stroke only sees one fourth of a turn of the cam, or 90 camshaft degrees. As we move closer to the bottom of the cylinder, a little before the piston reaches the bottom, the exhaust valve begins to open.
When does the intake valve open on a camshaft?
The intake valve opens slightly before the piston is at the top of the cylinder. As the piston moves down, air and fuel are drawn in. Shortly after the piston begins rising again, the intake valve closes for the compression cycle.
How does intake valve timing affect engine performance?
THIS IN EFFECT WILL PLACE YOUR RPMs A LITTLE HIGHER FROM PEAKING OR RUNNING OUT OF STEAM! THE REASON BEING A RETARDED CAMSHAFT WILL LET THE INTAKE VALVE STAY OPEN LONGER, TO GIVE THE COLUMN OF “INERTIA RAM” OF AIR/ FUEL TO CONTINUE FILLING THE CYLINDERS PAST BDC PISTON POSITION.
What happens when you change the camshaft timing?
Changing either affects engine performance, but a camshaft that is properly installed in an advanced position can noticeably improve performance. Four-cycle engines perform an intake, compression, power and exhaust stroke in each cycle. Each cycle requires two complete crankshaft revolutions.
How does the camshaft work in a four cycle engine?
Four-cycle engines perform an intake, compression, power and exhaust stroke in each cycle. Each cycle requires two complete crankshaft revolutions. The camshaft, which controls the action of the valves, rotates at half the crankshaft speed. The camshaft controls the movement of the engine valves.