How does a 2-stroke know what direction to run in?

LuckyStar64

PR Addict
So I was thinking about this... and yes, I think way too much! BUT! How does a two stroke always run in the same direction? What keeps the crank from spinning in reverse? Is it the ignition timing? Just kinda curious. Could it be timed to run backwards? --L*64
 
Actually a 2 stroke can and will run backwards, ever seen a yz250 with reverse? True story, bad CDI box. lol
 
Yes, has nothing to do with that. Bad timing will cause a 2 stroke to run backwards, you kick it and when it fires it rotates in the opposite direction. Yamahas had an issue with this, the root is the cdi box usualy. I've heard of brand new yz250's doing this after a few hours.
 
Hahahaha! Could you imagine heading to the gate, and when it drops, you head directly backwards? I've never heard of this before, but I was thinking that if you alter the timing, how would the crank really know what direction to go in? What year YZ did that? --L*64
 
02, I've heard of 14's doing it. Never hear of another brand, its really not a common issue among two strokes in general but yamaha had a cdi box issue that for rome reason they'd go bad and do it intermitantly.
 
Can happen with the flywheel being off time but usualy if you shear a key it'd be to far off to even run.
 
My Harley Golf carts run in both directions. they do it with the key switch and timing. That is how you go forward and reverse.
 
Husky's in the 80's had a bad problem with it. Ive never heard of newere Yamis doing it though! Wow!!!
 
Kawasaki Tecate quads and trikes were famous for this. On friend was climbing a hill, didn't make, Tecate quad started and was running backwards from rolling backwards. Another guy had the flywheel rebuild on his Tecate 3, and the magnets weren't placed right. He started it, pointed it at the open door, put it in gear, and ran into the back wall of his garage
 
Ever tried to ride a dirt scooter in reverse? Pretty fun after a 12 pack to try but I don't think it's possible. Lol
 
Yes they can run backwards. Had a '84 YZ125 that somehow my friend put something on wrong when he rebuilt it and started up ok, but when he let out the clutch it went backwards. We laughed like hell, then had to figure out what he did.
 
Hahaha! So if you advance or retard the timing-- it can actually run in reverse? I was checking a crank for play, and I found out that it was just as easy to push in the other direction. --L*64
 
I worked on golf carts for a local golf course and they do run both ways
Freaked me out first time I worked on one
 
Wow
reminds me of a long time back I was working on a cub cadet riding mower
Bought a used starter for it but it turned opposite direction than the one I needed because of the way it bolted on
Had a hell of a time figuring that outi
 
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