Squish??

Hi,

Flame all you want, but what is this "squish" you guys are always talking about, and where do you adjust it? Any info would be great. Everytime I turn around you guys are talking about the squish. Is it important? Will it wreak your bike if not set properly?

Thanks,

When the piston is at TDC, the squish is the distance between your piston and cylinder head.

Flaming rises it's ugly head when you post a new thread about a subject which has been discussed many times before. There is the search button in the menu... I'll answer anyway Squish is the distance between the piston & the head when piston is at the top position. It should ideally be 0.5mm-0.7mm. Stock bikes have usually squish 1.5-2.5mm which is horrible. You can adjust the squish by changing the cylinder base gasket/gaskets to thinner one(s). It is quite important. When the squish is set correctly, the bike has good amount of compression which makes the bike run better & faster. Big squish doesn't brake anything.

whoops sorry. Thanks for the replies though guys. I'm still to retarded to set the squish. If I took it to a small engine repair shop would they know *** I'm talking about and how to set it? I saw one guy use a piece of solder to figure out his squish but it looked way out of my league.

I'm pretty new to pocketbikes and i adjusted my squish a while ago, it's not that hard when you read all the squish related threads here . Well, measuring the squish is a pretty simple procedure.

- Take about 5 inches of 2mm thick solder and bend it to a |_ shape. The l part is about an inch long.
- Take out your sparkplug.
- Look inside the sparkplug hole & check what position the piston is.
- If the piston is at the top of the cylinder, then pull the starter cord slowly until the piston is in the lowest position ( not that accurate really ).
- Insert the l-shaped solder wire through the sparkplug hole and make sure the end of the solder wire touches the left or right side of the cylinder wall, not the upper or lower side ( might give false readings ).
- Then just pull the starter cord once ( might be quite hard to pull but keep going until the cord gets easier to pull.
- Now gently take out the solder wire and measure the "squished" part of the wire with a digital caliper etc.

Sounds pretty difficult but it isn't really

Thanks for the step by step. That sounds a little easier to figure out.

what do you mean by the left and right sides of the cylinder wall? its a circle, it doesnt have sides.

The spark plug hole is in the middle, The solder needs to go all the way from the middle to an outer edge of the cylinder, Even round objects have left and right sides, Depending on how you are looking at it, On a clock 9:00 is on the left side, 3:00 is on the right side.

What really should be done is a straight piece of solder as wide as the piston, taped in the same direction as the wrist pin, Just above it on top of the piston, That way the piston can't move side to side and give false readings.

Nick.

OHH i see now. Sorry!