took the muffler off so you could see the clutch bell, with the 3-inch pipe welded to it. it was an older aluminum-case homelite saw,lots of cutting and grinding was done to clean it up, then it was flat-blacked.there are 2 separate hinged arms from a sit-up machine holding the motor there, one has 2 screws in the bottom of the motor, the other has 2 in the top. the 4 holes were originally there to keep the engine tight inside it's aluminum shroud/case. it had a spring for tension but it got caught on something and stretched out...i dont ride it in the cold so i havn't put another on.