During a recent vacation out of state, I was able to go to a local motocross race and noticed several newer style KTM's being raced. I went over and checked each one and alerted the owner on how much the ridge on the mud flap had worn a groove on the Heim bearing housing on the swingarm. One bike was a brand new KTM520 only ridden 3 times and it already had a groove cut into the bearing housing.
Cut a piece of bicycle tub and put it around the Heim bearing housing or go buy a Heim bearing guard protector to keep the mud flap from rubbing the housing. It doesn't take long for the abrasive plastic in the mud flap to completely chew through your bearing housing. Its usually the two long ridges that run up and down the mud flag that does the most damage to the back side of the housing.
Cut a piece of bicycle tub and put it around the Heim bearing housing or go buy a Heim bearing guard protector to keep the mud flap from rubbing the housing. It doesn't take long for the abrasive plastic in the mud flap to completely chew through your bearing housing. Its usually the two long ridges that run up and down the mud flag that does the most damage to the back side of the housing.