There are several techniques to tune up the engine 2 stroke, the most common is re porting port design.
Re porting it too much like them are:
1 Changing the high port
2 Redirecting port window
3, Smooth channel port
4 Enlarge the size of the port
Of course, the above points should be made with the exact calculation for maximum results.
This time we will only discuss the high change port
Changing the port high mean duration of open and closed ports will change. Determining the number of high-port count is certainly have to use certain.
If a mechanic ever higher change ports on a cylinder block and the result could well be a reference to another mechanic if you want to change in the other blocks despite having a different spec.
The trick is to convert the size from mm to degrees rotating crankshaft.
example:
HRC Thailand ported determine the best height in the cylinder block NSR SP is as follows:
1 Lb Rinse: 42mm
2 Lb Primary & Secondary Transfer: 42mm
3 Lb Discard: 26mm
(Note: Deck Height NSR is 0 mm which means lips while NSR piston at TDC is a plot of the lip cylinder block or 0 mm)
So if we want to change the cylinder port block Yamaha RX King should use any number on each port if you want to refer to the HRC count ??
Surely one if we directly use the above numbers to be applied in block RX King.
We must first convert the units of degrees, after the obtained converted back into units of mm with a plus (Deck Height)
Then how to convert from mm to degrees?
The first we should first know the following data:
1 Stroke and stroke NSR RX King
2 The length of the piston Stang NSR & RX King
If the data is already known, we can draw on paper suitable data or if you want more accurately be using Auto Cad software.
For example menentuakn degrees open exhaust port on the block who want to emulate (Block NSR):
1 Create a circle with a diameter the size of a stroke NSR and describe its center point in the X and Y axis coordinates at the top point of the circle put a 0 degree crankshaft (this represents the degree rotating crankshaft)
2 Draw a vertical measuring length + stroke length with the position of the handlebar piston line through the center of the circle and the bottom end of the line to meet the bottom end of the circle. (This represents the central point of a series of cylinder + piston + crankshaft)
3 Create 0mm point at the upper end of the line (assuming the point 0 is the position of the piston when TMA)
4 Create another point (Mark with the letter B) on the vertical line was the size of a high-lb waste (in the example above is 26mm) means the distance from point 0 to point B is 26mm.
5 Use the term for that spacing aperture size of the long-term NSR piston handlebar (handlebar length represents the piston)
6 Needle term in position at point B and eye pencils coretkan to run in a circle that is able to reach the term (this represents the position of the handlebar piston in series)
7 Measure how many degrees of crankshaft position of 0 degrees to point to the last point with bususr 6 degrees.
Figures 8 degrees open exhaust port has been obtained.
Perform STEP 2 above to calculate the degree of open pit rinse and transfer.
After all found living now calculate how high the hole mm change in the block (Block RX King).
Langkah2nya are:
1 Create a circle with a diameter the size of a stroke RX King and describe its center point in the X and Y axis coordinates at the top point of the circle put a 0 degree crankshaft (this represents the degree rotating crankshaft)
2 Draw a vertical measuring length + stroke length with the position of the handlebar piston line through the center of the circle and the bottom end of the line to meet the bottom end of the circle. (This represents the central point of a series of cylinder + piston + crankshaft)
3 Create 0mm point at the upper end of the line (assuming the point 0 is the position of the piston when TMA)
4 Measure with a protractor numbers found on point No. 8 above and mark the circle and mark B.
5 Use the term for that spacing openings with long-term size of the handlebar piston Rx King (this represents the length of the handlebar piston)
6 Needle term in position at point B and eye pencils coretkan to run in a vertical line above the circle that is able to reach the term (this represents the position of the handlebar piston in series)
7 Measure the distance from the point to the new point 0mm obtained from point No. 6.
8 Distance high exhaust port RX King has been obtained.
Perform STEP 2 above to calculate hole spacing rinse and transfer.
After all we need to know the figures obtained Deck the king RX height, then measure the distance obtained after the port has been obtained respectively Deck plus its height.
Meanwhile, if you want to widen the exhaust port is a maximum of 70% of the diameter of the piston
unless the dump pit design has NSR SP poles as it can be made even wider.
Example: NSR piston diameter is 59mm, the width is the maximum exhaust lb 70% 59x = 41.3mm rounded to 42 mm, if more than 42mm then worry about the piston rings lb waste will tend to suppress excessive cylinder wall to the boundary of the cylinder will be easy to wear.
