Hi,

I found this engine with a few other engines, from its looks It looks the same as a GX31.

It came with a gear reduction unit attached and an electric starter, I put a fuel tank on it and attached the wires of the starter to a 12v battery and it started right up! I would guess it was on a bike or scooter or something, but it looks barely used.

it runs pretty sweet, but the only thing with it is that it has a fin missing off the flywheel, so I've got second thoughts about putting an adapter on it and spinning a big prop.

Do you think its ok to still run a prop on it? I was also thinking of electronic ignition, but Ihave no idea how to go about it.

I see it has a wedge shaped piece missing from the flywheel

With the gear reductin, you could run a REALLY big prop!! I am sure CH could advise you on an electronic ignition, as can others. Good luck.

The gear reduction makes the ratio 5:1, but it weighs 900 grams. So I don't think it would be too great to use, although I could be wrong.

Is it alright to cut the portions off the flywheel that I've shown in the pic? This would be the only thing I can do with the flywheel becuase of the chunk thats missing, I would guess that it was dropped by its previous owner.

Probably yes. I'd leave the inner round part/dome intact - don't cut in too far. Need to cut further than the crack goes in though. Fins can be removed on the flywheel at the same time

Yes defo balance it when you've done it.

Well, you could do it, but I would consider it a "bomb waiting to explode" until you had a bunch of time on it for testing. Better to use electronic ignition if you want to get rid of the magneto weight. You can use a regular two stroke ignition system; it doesn't matter that the spark will fire both near TDC compression and TDC exhaust. Trust me, I've done it.

Try www.ch-ignitions.com

AV8TOR

I'd think with that gearbox on there, you could easily sell or trade that to a moto-bike guy for a real GX31, or at least one of the Hua Sheng clones. Something to consider, at least. If that gearbox comes off and you end up not wanting, I'd be interested in it.

The gear box only fits this adapter plate that fits onto the engine, but if its still of use to you let me know,

I reattached the electric starter on the engine and started it up again, and while running a tiny peice fell off the flywheel! so I'm definitly not going to be running that flywheel.

I have no idea how to do to whole electronic ignition thing, how would I go about it? and is there a significant difference between a $100 system and a $50 system?
I am trying to keep this as low budget as possible, for the meantime anyway...

Well, basically all you need is a hub with a magnet in it, and a place (adjustable) to mount a sensor. Some people have the ability/tools to make these items themselves, and some do not. Best to give them a call at www.ch-ignitions.com. They have worked with the Honda, and are very helpful. I believe www.carrprecision.com also sells kits for converting the Honda(s).

There are only two easily obtained and fairly inexpensive ignition systems that I recommend; the CH Ignitions unit, and the RCEXL system. There have been various problems with some of the other cheaper ones you can buy from overseas.

Sorry, I don't have any better pictures of this one that I converted, as I sold the plane and engine.

Good luck,
AV8TOR

<span style="font-family: 'Times New Roman'; font-size: medium; "><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; padding-top: 0px; padding-right: 0px; padding-bottom: 0px; padding-left: 0px; background-image: initial; background-attachment: initial; background-origin: initial; background-clip: initial; background-color: rgb(255, 255, 255); font-family: Arial; font-size: 12px; background-position: initial initial; background-repeat: initial initial; ">I'm interested in that gearbox, I'm sure I can make an adapter plate if I need to, but how bad will shipping be from AU to Canada, I wonder? My postal code is R2C4G2, if you want to check. My best efforts on the australia post website indicate $50-60 shipping slow boat style, which would be a deal killer for sure.</div></span>