Poor cylinder casting?

[nickaloadien]

Every kit I buy the cylinder ports always look like this so i’m starting to wonder, are these specifically casted like this with the port timings worked out or is this just bad casting? I usually port out all that inner material. I am planning on properly opening up these ports this time hopefully I don’t screw up the timing!

Also I wanna deck the head this time, what is a good amount to sand off for squish?

 

[darwin]

What you have there is cheap, AKA you get what you pay for. Molds are reused past there use date, no finishing and cheap metal. Don't feel bad this hobby is all about building a low-cost fun ride, mostly.

 

[Whitewill1412]

That's bad. Must be a real cheap one. Mine wasn't like that. How much did you pay for it? Where did you buy it?

 

[Chainlube]

Every kit I buy the cylinder ports always look like this so i’m starting to wonder, are these specifically casted like this with the port timings worked out or is this just bad casting? I usually port out all that inner material. I am planning on properly opening up these ports this time hopefully I don’t screw up the timing!

Also I wanna deck the head this time, what is a good amount to sand off for squish?

Typical Ebay, Amazon, Aliexpress off brand kits, have lots of casting flash. Just file it off and round the inner edges, you won't mess up the timing at all.

For the squish, put your piston, base gasket and cylinder on the case. Clamp it down, I use a bar clamp and very little pressure, Turn the engine over and measure the piston to the top of the cylinder clearance when at TDC. Add that number to the thickness of you head gasket, now that is your squish amount.

 

[Street Ryderz]

Every kit I buy the cylinder ports always look like this so i’m starting to wonder, are these specifically casted like this with the port timings worked out or is this just bad casting? I usually port out all that inner material. I am planning on properly opening up these ports this time hopefully I don’t screw up the timing!

Also I wanna deck the head this time, what is a good amount to sand off for squish?

Just match the outer flange area dimensions on the inside and don't take more than 1mm from the top (inside) for a best result, unless your going to through on a bigger intake, carb, pipe and stuff it's kinda pointless to go whole hog on the porting.