This is for all Husqvarna/KTM 2 Stroke engine cases up to 300cc. The stock cases are cast aluminium and lack the steel reinforcement inserts that are often found in their 4 Strokes at the swingarm pivot point in the case halves. This omission of this insert, combined with steel frame flex causes the holes through the crankcase to become deformed over time and hard riding by the hardened steel swingarm bolt. This image of a 2016 TE 125 motor shows the stock case lacking the steel sleeve insert. This in turn allows the engine to move and vibrate causing the swingarm bolt to become loose. Which in turn forces the motor mount and swingarm bolts to be over-tightened regularly to reduce vibration. This will eventually cause the frame tabs to become deformed and over time metal fatigue will cause cracks and failure. This is in addition to the damage being done to the case. Don't allow this to happen to your 2 Stroke machine! At Zip-Ty Racing, we want you to enjoy the race tricks we use in our race bikes for your own. Our steel insert modification solves the problem! As you can see the case is machined to accept a hardened steel sleeve insert to keep everything strong and square. Another example showing how Ty never allows a problem to slow the team down and solutions lead to results.