Never, NEVER use an exhaust brake with a 2 stroke. An exhaust brake works by plugging up the exhaust pipe with a butterfly valve with bypass to let some exhaust through. This works well with a 4 stroke in that it just makes it harder for the piston to push out the exhaust-hence the braking effect. On a 2 stroke-yes you would also get the braking effect, but with the over lapping of the intake and exhaust cycles, and the fact that the piston doesn't actually push the exhaust out of the cylinder, the blower is what pushes both the fresh air in and helps the exhaust also leave the combustion chamber. Hence, with a 2 stroke, all the back pressure from the exhaust brake would be absorbed or taken by the blower-most likely blowing it right off the engine. Good Luck, TomC