All Bolt Patterns are Based on a Circle. What Size Head Bolts/Studs are used on the GX390? Do you put in Bigger ones for Racing?
All my 70's to 90's Old Skidoo/Rotax 2 Stroke Engines use either an 8mm Bolt/Stud and a (4 or 6) Bolt Pattern-based off either a 94mm or 100mm Bolt Circle.
The GX390 uses a (4) Bolt Pattern-based off what Circle?
Is 96mm the Largest Bore out there?
Here is a Drawing of a 110mm Bolt pattern. From photo's, it looks Larger.
All my 70's to 90's Old Skidoo/Rotax 2 Stroke Engines use either an 8mm Bolt/Stud and a (4 or 6) Bolt Pattern-based off either a 94mm or 100mm Bolt Circle.
The GX390 uses a (4) Bolt Pattern-based off what Circle?
Is 96mm the Largest Bore out there?
Here is a Drawing of a 110mm Bolt pattern. From photo's, it looks Larger.