i need to know how to make a 2 stroke run backward?

i am converting a pocket rocket from electric to run on a weed wacker engine but, the engine rotates the wrong way. any advice on how to get it to run the other way. i am most confused on how to change the timing to fire at the right time going backward. thanks

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rickharris7 years ago
Crankshaft may have been intended  - Actually it is a function of the port timing.

Some 2 strokes will run as well backwards as forwards if you change the starting mechanism  - electric motor, Cord pull etc to mke the engine turn backwards.

Some - especially those optimised for power or fuel consumption will only run one way see above.
yah, cause, unlike 4 strokes, there's likely no valves, just holes in the cylinder wall. the magic of making a 2 stroke like that run backwards, is taking the up/down piston actuated valving into up/down piston actuated valving.

with those cheap 2stroke bike motors, you just install them backward, change the timing of the ignition magnet/points, and they run backward perfectly. personally, i'd get something like the TIM-4 made up for it.
kelseymh7 years ago
Gears.  Forward is defined by the way the pistons are connected to the camshaft.  You need an appropriate transmission to get reverse.
dude 2 strokes dont have camshafts
dude, he miss-spoke.  He meant to say (type) crankshaft.
ya i figured that lol
lemonie7 years ago
I'd arrange the transmission so that you get the right result. Messing with the timing may be tricky, the compact casings can obstruct you moving things.

seandogue7 years ago
At the risk of being obvious, could you turn the motor around 180 degrees and drive the load from the other side? (or is the shaft vertically oriented?)