okay here we are with a piece of paper so we've got our piece of paper put the
square edge down into there get the joining side there here's our exhaust
port okay now I'm just going to scribe on the piece of paper there so what I
need to do is we need to hold the piece of paper in there so you can use a
sponge roll up a sponge bit of sponge like that stick it in there you can you
know you can blow up a balloon inside there put sand inside there and pack it
up you know whatever you want really let's just stick something in there to
hold the paper in there okay put the square edge like if you've cut a piece
of paper take the square edge and put it right down to the bottom of the port
because we're going to actually do two measurements here I'm going to do the
scribe the line and then I'm going to measure from the very 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 just get a fine pin and I'm gonna go over and
scribe the port here on there now you can if you like you can use some paint
but if you paint if you spray paint in the port okay what's probably going to
happen is it's gonna seep between the edges alright so what I would suggest if
you're going to go for that approach is to get yourself a little brush you know
and maybe dab some paint on it and then go into the corner and you know paint
the area also do the exhaust port from the outside if you can I know you can oh
you you can trace it from the inside but the problem is there is is that if you
do that is you've got to account for the fact that the ports are sham furred on
the inside and we don't want the outside of the
sham fat edge you know in a manner that might be a little bit greater than the
size we actually want the port size itself so here we've got our piece of
paper
okay so that's our port our exhaust port and now the next thing we want to do is
we want to take some measurements off there one thing I wanted to measure was
the to the top now I'm going to measure to the outside of that black line I've
got 23.6 so just take a piece of paper and write down you
write down your measurements okay is 23.6 is a port to deck
the deck is the top of the cylinder okay next measurement we want to take is
the total height of the port again we'll go from the outside
12.5 for the height that's the total height width of the port to 25.5 width
now you'll notice that it's got a curved top all right what we're going to do is
we're going to measure the curved top we're going to take two measurements
here and you will see in the new version of software how this is done so we've
got from the edge so we're just going to draw a line across the air and assume
that's a flat top port okay the curved edge so now what we're going
to measure is we call this part the segment okay this little part here this
is the segment alright so we want to take this segment height so the segment
height is from the inside of that line 3 millimeters for a segment height
next thing we want to measure is the radius of our segment or the radius of
our of the top of our port okay so you can use pretty much anything I've found
the old air filter rubber off the air filter you see it actually matches the
edge of it like that so that's okay so we'll just take that 57 millimeters
total so half of 57 is 28.5 so 28.5
is our segment radius SR okay so now we know the radius of the
top there then we need to get the two radii for the bottom of the port and
again just use anything round anything round shape and again anything that just
matches the the radius there in the corner it's a little on the large size
yeah that matches it I'm happy with that okay that matches it so we just measure
that and that is 9 millimeters so the radius is 4.5 millimeters
I'll just check the borel size yeah 44 millimeters I'll write that down 44
bore size okay the bore size and the the width here okay is the paper width so we
need to know the bore size as well because we've got to turn that from the
paper width this paper width into a chordal width the chordal width being
the actual width if we measured it straight across there with a set of
calipers I can do it off the paper but you know it's not very accurate and you
can just do it in the software so you've got to know is the bore size and the
width and we've got our 23.6 port to deck size with the
total height of 12.5 total width on the paper is
25.5 so I'll take that 25.5 put it into the software
take that 25.5 width put it into the software with 44r millimeter bore
and that'll give us a chordal width we'll do the conversion with okay the
next one is to do the outside face okay so on the outside face what we can do is
we can just hold that on there you can stick the paper to there if you like all
right it's the inside part that we want I've just got a piece of pencil lead
here same thing applies as the previous one we measure the the width the height
and then we put a line dissecting from the corner to the corner and then we
measure the segment height of this one okay like I explained before no need to
repeat that but we need both of these values for the inlet from the cylinder
to the exhaust port to the outlet at the flange to put into our expansion chamber
software and I will be doing that in the next video and explaining a few things
in the process of doing that that'll be a separate video I try to make those too
long because they do get a bit long and windy and boring after we've done that
we're then going to move further into the topic of porting as I explained in
the first video so the next measurement and the final measurement we've got is
the exhaust port length so we'll just put the verniers against the edge of the
port and we'll measure that all the way out just until we get center line and
they do that centerline of the port okay any finger there so I can feel it
right here 24 millimeters for the port length is 24 millimeters