Jock itch (tinea cruris) is a fungus, the same one that causes athlete's foot and scalp ringworm. The groin area is the perfect place for the fungi to grow and cause a fungal infection because it is moist, warm and dark.
The camshaft lift is the resultant net rise of the valve from its seat. The farther the valve rises from its seat the more airflow can be provided, which is generally more beneficial. Greater lift has some limitations.
The camshaft and magneto were driven by the crankshaft through a three-member train of spur gears (see Figures 9, 10 and 11). The Wright Brothers' Engines and Their Design Leonard S. Hobbs. The cam-shaft is hollow, and serves as a channel for the conveyance of lubricating oil to each of the camshaft bearings.