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'82 R100RS Camshaft Question

BC1100S

Left Coast Rider
Is it typical for the cam to appear offset to the tappets? I've disassembled to the engine case and it looks like only half the cam lobe contacts the tappet. Cam and tappets appear in fine condition.

Thanks in advance for your input.
 
cam off set

hi, there is some off set to cause the cam followers to rotate for various reasons ,hope this helps ,good luck ,jimmy
 
Yes. The airhead engine uses 'flat tappets' like many other engines. The base of the tappet is not actually flat but is slightly concave. Similarly, the cam lobes are not flat but have a slight taper. The combination allows the tappets to rotate and draw oil in between the tappet and cam.

If you would like to learn more or just have a healthy skepticism, Google search using the key words 'flat tappet cam design' and a wealth of information will be provided. Also, each tappet should be returned to the respective lobe when replaced. Otherwise, it is considered best to replace or regrind the tappets and break-in the camshaft again.
 
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