advice on shortening two stroke intake?

GoldenMotor.com

motor_bike_fanatic

New Member
Jul 26, 2011
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Pennsylvania
I have heard some people suggest that a straight intake improves port matching. so if I cut the intake where it is angled, will that improve low end power and torque for better hill climbing ability?
 

biknut

Well-Known Member
Sep 28, 2010
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Dallas
I have a MM shorty manifold, and I can't tell if by itself it makes more power, but I can tell it doesn't make any less.
 

wheelbender6

Well-Known Member
Sep 4, 2008
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In a general, long, gently curving intakes boost low end power while short intakes boost higher end power. There are exceptions to every rule.
One of the better ways to boost low end power in a two stroke is to add a reed valve to the intake. You will need to adapt one from another small engine like a chain saw.
 

wheelbender6

Well-Known Member
Sep 4, 2008
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A reed valve is little more than a check valve. It allows things to flow only in one direction. To my understanding, reed valve prevents spent exhaust gases from contaminating the fuel/air mixture from the carb.
I bought a reed for a chainsaw from ebay for around $10. I am working on building a housing from aluminum stock.
 

ducedave

Member
Apr 17, 2011
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Mentone Ca.
A reed valve is little more than a check valve. It allows things to flow only in one direction. To my understanding, reed valve prevents spent exhaust gases from contaminating the fuel/air mixture from the carb.
I bought a reed for a chainsaw from ebay for around $10. I am working on building a housing from aluminum stock.
a reed valve gos between the carb and cylinder and block air fuel load from exiting the motor HT are piston port blocking so with a reed you MUST cut or drill a pass through in the skirt of the piston and yes they work vary well I had a hard time sealing mine a stack of aluminum plates tried paper, rubber and 2 part epoxy what worked for me? leather
 
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