1970-1979 Ski-Doo Snowmobiles Service Manual, Page 55Get this manual
48 Lug Damage Lug damage as shown in Figure 22 is caused by lack of snow lubricationRatcheting Damage Insufficient track tension is major cause of ratcheting damage to the top of the lugsSee Figure 23Ratcheting damage can also be caused by too great load and constant "jack-rabbit" startsOvertension Damage