Unlocking the secrets of 2 stroke porting, part 2 - How to trace and measure ports.

Well, here we are with a piece of paper, so we have our piece of paper. We put the square edge down, take the joining side. Here is our exhaust port. Okay, now I'm just going to write on the piece of paper. What I have to do is hold the piece of paper there so you can use a sponge. Roll up a sponge. A little sponge like that. Stick it there. You know, you can blow up a balloon inside. Put sand inside. there and pack it in, you know, whatever you want, really, let's just stick something in there to hold the paper, okay, put the square edge like you cut a piece of paper, take the square edge and put it all the way down. of the port because we are actually going to make two

measure

ments here.

I'm going to draw the line and then I'm going to

measure

from the top of the port to the top of the cylinder for another purpose which I'll explain later, now all I'm going to do is get a thin pin and I'm going to write the port here and beyond. You can use a little paint if you want, but if you paint, you spray. paint on the port, okay, what's probably going to happen is it's going to seep in between the edges, so what I would suggest if you're going to go with that approach is get a little paintbrush, you know, and maybe apply a little bit of paint to it and then go to the corner and you know, paint the area and also make the exhaust port from the outside if you can.

I know you can, oh, you can track it from the inside, but the problem is if you do, it's you. We have to take into account the fact that the

ports

have a fake lining on the inside and we don't want the outside of the fake thick edge, you know, in a way that might be a little bit larger than the size that we actually want for the size of the port. So here we have our piece of paper, okay, that's our port, our exhaust port, and now the next thing we want to do is take some measurements there.

One thing I wanted to measure was to the top. I'm going to measure to the outside of that black line. I'm 23.6, so just grab a piece of paper and write, write down your measurements. Okay, 23.6 is a deck port. The cover is the top

part

of the cylinder. Okay, next. The measurement we want to take is the total height of the port again, we will go from the outside 12.5 for the height which is the total height of the port at 25.5 wide. Now you will notice that it has a curved top. What we're going to do is measure the curved top, we're going to take two measurements here and you'll see in the new version of the software how this is done, so we have it from the edge, so we're just going to draw a line in the air and assume which is a flat top port, okay, the curved edge, so now what we're going to measure is we're going to call this

part

the segment.

Okay, this little part here, this is the segment. Okay, so we want to take the height of this segment so that the height of the segment is from the inside of that line 3 millimeters for a segment height the next thing we want to measure is the radius of our segment or the radius of the top of our port, okay, so you can pretty much use Almost anything I found was the old air filter rubber from the air filter. You see it actually matches the edge like this, so okay, so we'll take those 57 millimeters total, so half of 57 is 28.5, so 28.5 is our segment.

SR radius okay, now we know the radius of the top there, so we need to get the two radii for the bottom of the port and again use anything round, any round shape and again anything that matches the radius there in the corner . a little on the large size, yes, that matches. I'm happy with that, okay, that matches, so we just measured that and it's 9 millimeters, so the radius is 4.5 millimeters. I'll just check the hole size. Yes, 44 millimeters. write that 44 hole size okay hole size and width here okay it's the width of the paper so we also need to know the hole size because we have to convert that from paper width to a string width .

The width of the rope is the actual width, if we measure it in a straight line with a set of gauges, I can do it without paper, but you know it's not very accurate and you can do it in software, so you should know what the actual width is . hole size and width and we have our port to deck size of 23.6 with an overall height of 12.5. The total width on the paper is 25.5, so I'll take that 25.5 and put it into the software. I'll take that 25.5 width and put it into the software. with a diameter of 44r millimeter and that will give us a chord width, we will do the conversion, okay, the next one is to do the outer face, okay, so on the outer face what we can do is just hold that there. stick the paper there if you want, okay, it's the inside we want.

I only have a piece of pencil lead here. The same applies as above. We measure the width, the height and then we put a line that dissects from corner to corner and then we measure the height of the segment of this, okay, as I explained before, we don't need to repeat that, but we need both values ​​for the input from the cylinder to the exhaust port and the outlet on the flange to fit. in our expansion chamber software and I'll do it in the next video and explain some things in the process of doing it, that will be a separate video.

I try to make them too long because they get a little long and windy and boring, after we've done that we'll get further into the portability thing like I explained in the first video, so the next measurement and the final measurement we have is the length of the exhaust port, so we'll just put the vernier calipers against the edge of the port and measure it all the way to the center line and they make that center line of the port, okay, any finger there, so I can feel it right here. 24 millimeters for port length. 24 millimeters