In the engine case. They are attached to piston rods and go up and down.
Probably not, especially if the rods were thoroughly reconditioned and the "big end" was honed back into shape.
right 45 degrees
The piston is inside an engine, under the valve cover, under cylinder head. it is the piece that transfers the explosive energy into rotating motion along with the connecting rods and the crank shaft. It all however has to go through the whole drive train to get to the wheels: the the transmission,the drive shaft, the differential, and so forth. There is also a piston inside a typical brake caliper, sometimes more than one.
No, a cocci are round and bacilli are rods.
It is when you go through the inside of the motor and replace rod bearings main bearings piston rings cam bearings and in serious cases pistons and rods and a valve job on the heads it all depends on the engines problem as to what you do.
If neither piston are moving you either have one of three problems. 1) You could have a sheared keyway between the flywheel and the crankshaft. (hopefully it is this one as it is an easy repair and very cheap) 2) Both piston rods are broken. 3) The crankshaft is broken.
If the pistons are bad it should be smoking a bright blue color out of the exhaust. Are if a piston skirt is broken it should be knocking all the time. If there is a whole burnt in the piston you will not have any compression on that cylinder. Most of the time pistons just don't go bad.
long ones are exhaust
If they weren't marked there's no way to tell which cylinder they came out of. You might get away with putting them in where ever. But it usually doesn't work out very well. Best thing to do at this point is to take the rods and caps to a machine shop and have them re-sized. Then you'll be starting off fresh and can put them in any cylinder.
pistons are flat on top. then as you go down the sides you will pass several grooves. below that are the piston skirts. they are basically just the sides of the piston
Installing a bigger piston is one way to make a 150cc go faster. There are also kits that can be purchased to modify a 150cc to make it faster.