I don't fly with gasoline yet, but question the sense of conversions. With places like B+B with ready to go engines, with engines like Fuji out there ready to go for $300-$400, with a decent used market where Zenoas are selling for say $300 is it really sensable to convert ? By the time you buy an engine, even a cheap engine much less a new one or recon, do machine work, buy the conversion parts and wonder if a carb will work or the fit will really be right, it just makes me wonder. I'm not knocking conversions, just looking to justify why and if that may be a better way to go or not.
David

its all part of the hobby you build an airframe from a kit or scratch build. its the same with an engine ..... cheaper... sometimes yes sometimes no. satisfaction from flying what you salvaged from a weedy or a chainsaw...priceless.
i got my first g62 from B&B all my other engines were home built from 25cc homelites to 100cc husky saw engines. some of the husky engines can use the g62 prop hub for easy ign conversions

LETS SEE Fuji 32 magneto $300.............................................. ................Fuji 32 EI $400
New Ryobi 31 $60, Wacker mag conversion $60....................... New Ryobi 31 $60, CH ignition $120 conversion kit, Wacker Muffler and mount $43.
Garage sale Homelite 30 $10, Wacker conversion $53................Garage sale Homelite $10, CH ignition conversion and Mtr Mt $132, Wacker muffler $25
Looks like about %50 off by rolling your own. A little garage sale cruising will find lots of "broken" weedies in the $10 range.
Sorta like ARF vs Kits vs Scratch building

It all depends on what sort of person you are- i get just as much satisfaction out of the time spent late at night in my shop carving an airplane powerplant out of a raggedy chainsaw engine as I do
flying the darn thing- I'd just as soon mount the engine to a bench and run it and tune on it as I would to drag something to the field and fly. I can tinker with the engine at night- or in a spare hour here and there- flying can only happen on a weekend and involves a mini road trip- and I don't get many of them with that much spare time these days.

Conversions are for "engine guys"- period. If you don't have the deep, burning, engine-tinkering mentality- then go buy a ready made one.

It's not so much the money as the accomplishment and satisfaction- plus its not easy for me to spend $400 all at once. But- I can spend it over a period of months- on this little piece and that little piece-
you guys know how that works.

I have a small lathe and mill. I can make anything I need to within reason- I have never bought a mount, prop hub, or muffler. I am trying to get geared up to make my own ignitions.

I have been doing this for years, but just for ref- I can take a $140 poulan from Lowes, buy $120 worth of ignition parts and in my spare time build EVERYTHING else- and I end up with a sweet-running powerhouse.

Worth it???? YEAH.

If you want to save big money it won't do it . You have to want to do it just because you can because it is not going to make you money . I sell parts and mufflers and complete engines, it gives my money to buy another to convert and get more materials , I do fly my conversions but I have alot of time to kill .

i bought a homelite 25cc off ebay for 22 bucks with shipping. so far i have a total of 28 bucks in it. my dad is a tool maker so i asked him to make me some parts. had to buy a 4 dollar spark plug to cut down on interference.

It makes perfect sense to me. First I am an engine guy, so this is something new to explore. A big reason for me is to have something that isn't available. This Decathlon I am putting the honda 4 stroke on is going to be unique. IF fugi or the others later release a 4 stroke then nice, someone can now buy out of the box what I had to build. Money wise, it makes sense too, 0~$60 for a 31cc engine, $60 for the conversion kit delivered to you, and you have a power plant for $60 to $100. Should the weedie put out a little less power, you just up the CC some, if you would use a 27cc factory engine, just use a 31cc weedie. The blocks are often the same between CCs in a similar range.

fuji does now makes a four stroker http://www.fujiengines.com/engines/fjig0225.html

but i fear itll have less power than the Honda, i have on occasion heard that fuji engines are underpowered.

save money is not the only reason to convert. I have a 3W 100 in my 1/3 Extra but I feel proud of my Extra 3D with a Poulan 36 with my own electronic ignition system. Something special will be in convert engines so you can see in the workshops expensives engines near the converted ones

Retail prices.....The Fuji 34cc four stroke is $799...
A Honda GX25 is $175..
A Stihl 64.9cc four stroke is $400 .
Shindaiwa makes a 34cc now, not sure of the price..
Fear not, the Big Daddy of all four strokes is coming, an 80cc Shindaiwa....