125-200cc Husky 125 intake port..

Hello all,, does anyone know what the rectangular intake port at the base(mating surface) of the cylinder is for?,can it be open'd up slightly for a performance gain.. It sits above the same type of rectangular cut in the case,,just above the reed valves... Always Tinkering..

Yes sir that's her,,that one looks like its been open'd up a tad,it looks more rounded..Kelly can i open it up a bit there and what would be the benefits?? Thanks..

I open the rear transfer up on the 165 to allow more room for welding the rear channel up on the sleeve. If you look at the profile in the cylinder of that port you will notice that it is very shallow and designed to shoot up flow up the rear of the cylinder to help push exhaust out the exhaust port. It really is more important to keep velocities high there than ultimate flow. Opening the port up will slow down the velocities. It is a trade off for the 165 of re-enforcing the sleeve vs best flow characteristics. JMO

Im with Walt on this but you could match it to the cases by laying a base gasket on there but really dont see any gains to be had

So going with the flow characteristics of the port to help excavate exhaust gas,,the tunnel effect( big to small) would'nt help flow faster??wally,,john thats what got me thinking,the gasket out line on the case and cylinder?, atleast try to match the 2 ports(cyl-case) close to make flow a bit easier.. The case port is quite a bit larger than the cylinder port..

Yes, you can open it to match the case and maintain the big to small aspect of the port. The top side needs to maintain it's high angle of about 65-70 degrees, sort of aimed toward the plug. This is a very important scavenging port and help pull transfer flows up the rear cylinder wall to purge burnt gasses.

Normally referred to as the rear boost port.