Shaft drive vs. belt drive?

Discussion in 'Lawn Mowing' started by dedgrass, Feb 11, 2003.

  1. dedgrass

    dedgrass LawnSite Member
    Messages: 19

    I have a Scag Super Z that I need to swap out and I'm looking at a Grasshopper/Woods liquid cooled gas model. What is the advantage or disadvantage of shaft vs. belt drive?
  2. Sam-Ohio

    Sam-Ohio LawnSite Senior Member
    from Ohio
    Messages: 304

    The advantages of shaft drive over belt drive are pretty much self evident.

    Shaft is a bit more efficient at transmitting power or torque with less friction loss of energy.

    Shaft is many times more reliable - virtually never breaks, or requires replacement. If there are universal joints in the shaft, our experience is that 3000 hours is usually the minimum, and you may get upward of 5000 hours before they need replacement.

    One of the problems with any type of belt drive is the belts fellow traveler - the idler pulley. Idlers cause much of the friction and are as big of a maintenance problem and expense as the belt itself is.

    There are places where the use of a shaft drive is just not practical. The drive system inside the mower deck , that drives all three blade spindles is a good example. In this application a shaft would allow no "forgiveness" and the flywheel effect of the blades would cause much damage if just one of the three blades were to hit something [like the ground] and suddenly slow down. In this case a belt would likely absorb the shock and survive it - a shaft won't absorb it at all , and something would break.

    Both systems have their place where they are most practical and reliable to use. The Grasshopper that you mentioned has used both shaft drive, and belt drive in the design of their machines , and they have a very practical and efficient system.

    Only one issue that I know of with a Grasshopper , is that they like level ground - and hills are not their Friends. Since you are in Illinois , hills may not be something you have to worry about .
  3. J&R

    J&R LawnSite Senior Member
    Messages: 835

    if you liked the Scag way not buy a Scag turf tiger they come with 27 hp water cooled Kz eng. and shaft drive.

Share This Page