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.
RPM means rotation/revolution(s) per minute,rpm is concerned to Engine whose pistion moves in rotation inside the drum , RPM is important bcoz larger the RPM larger the force it produces whic moves the wheel of your bike , or car.