Anyone know where I might be able to buy a small (like 50cc) clockwise turning two stroke? I have looked and can’t really seem to find a place that sells them. Alternatively I could run a counter-clockwise two stroke backwards but ideally it shouldn’t have to come to that. Any thoughts? A website or brand name is helpful as well. Thanks
Clockwise two stroke
- Thread starter Barîb
- Start date
Denny
Canned Monster
You could just turn the engine around.
No that’s the issue, I’m modding a little razor electric dirt bike and I am going to put a 50cc weed eater engine in it. It fits in the frame the drive side is on the right side (If you are sitting in the bike) and cannot be changed. If I run the engine on that side it will run in reverse. I have heard you can run a two stroke in reverse, is that possible? Or where could I find one that runs clockwise.
madprofessor
"Loose Cannon Creations"
HVACR reciprocating compressors with reed valves and without an oil pump, that run on 3-phase electricity, can run either direction. I've snatched loose quite a few that had seized up by reversing 2 of the leads. But I've never heard of any fossil-fueled motor capable of that due to the timing of the valves, even of a 2-stroke rotary disc valve. Google it.
karl
Well-known member
Sure is, my west bend is set up so changing the flywheel/ recoil determines what direction it runs.
2 cycles do not have valves or camshafts, and the ports do not know or care what direction the crank is turning.
All the ports see is a piston moving up and down.
Lets do it!
Oh.
Anyway back on topic, I would start by turning the motor over to top dead, and looking at the flywheel magnet
in relation to the coil. Then lap the flywheel to the crank so no key is needed, then put it back on the crank
so the offset of the magnet to the coil is on the opposite side. Make sense? That should get you close enough , a couple degrees of timing is
not going to make or break it.
Now all that's left is the recoil, little bit more difficult. You could just remove it and use a manual
recoil cup, wind the rope around it for every pull.
madprofessor
"Loose Cannon Creations"
Good stuff to know (after all these years finally). Can only remember back to '72 Kawasaki Bighorn 350, my last 2-stroke. My first thumper, and that's all it took to wean me off of weinie bikes. All single-banger 4-stroke thumpers after that all the way up to 650cc.
anderkart
Moderator
You could install the engine backwards and use a jackshaft:
I must admit, I do not understand. All I was planning to do was reverse the pull start to wind it the other way. What I don't understand is the "lap the key to the flywheel crank so no key is needed". I'm new to two strokes, could you explain further, my "expertise" is not in engines yet. The engine below is probably pretty close to what I would use, and then I'd throw on a little sprocket for the clutch.
I have been considering this, and it may help with spacing with foot pegs, I just don’t feel like buying one haha. Will probably end up going with this, just wanted to know what y’all thought about running a two stroke backwards. Like is it practical, how to do it (which I addressed earlier I don’t understand), etc. Anyways any info anyone can bring is helpful.
Basic 2 strokes can run either way.
As mentioned the piston doesn't know which way the crank is spinning.
I had the Polaris snowmobile electronic reverse.
Cool to watch, stop, hold the brake, push the reverse button switch.
The engine would come to a near stop and start spinning backwards.
The oil pump becomes a challenge if used
Its all based on the ignition timing before TDC
That setup used a digital CDI that manipulated ignition timing
You might be able to reposition the pickup equally to the other side of TDC
As mentioned the piston doesn't know which way the crank is spinning.
I had the Polaris snowmobile electronic reverse.
Cool to watch, stop, hold the brake, push the reverse button switch.
The engine would come to a near stop and start spinning backwards.
The oil pump becomes a challenge if used
Its all based on the ignition timing before TDC
That setup used a digital CDI that manipulated ignition timing
You might be able to reposition the pickup equally to the other side of TDC
madprofessor
"Loose Cannon Creations"
Not endorsing you doing it here, but to explain "lapping "...............The flywheel's rotational position on the shaft sets the timing for the motor. They come with that position set via a keyway in the shaft and in the flywheel, with a piece of keystock stuck in it. You can throw away the key if you want to, and change the rotational position of the flywheel on the shaft to change the timing (where the spark plug fires during the rotation of the motor). It's a friction fit flywheel he's talking about, and the nut on the shaft holds it tight on the tapered shaft in its new position, just not well enough without lapping. To "lap it in" you smear valve grinding compound on the shaft, push the flywheel onto it, and twist the flywheel back and forth until the gritty compound eats it into a perfect fit. REMOVE ALL COMPOUND!!! Clean that sucker good.