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Discussion Starter #1
Raced APBA (American Power Boat Assn.) Stock Outboard and (alky-burning) Outboard hydros in the mid-Sixties to early-Seventies.

Had an RD400C with some usual suspension upgrades which I recently gave to a pal because I had to move and was tired of packing stuff (it hasn't run in a while). The proviso was that when he/we get it running, I can borrow it back.

FWIW, i have a couple of "antique" (Fifties) chainsaws to restore (and hop-up, heh, heh, heh!!!) (for no very good reason other than this is what 2-stroke gearheads DO) (one friend never tires of telling about the day he walked into my shop and found me "porting" my brand new Sears shop-vac) (how do you like that string, parentheses fans?!!). Come on, I have TWO Foredom flex-shaft grinders; I can't help myself!!

I have a bunch of obsolete alky-burning outboard racing engines (125/250/350cc)and junk in boxes, and have a mad urge to put it together and run it. One of the big advantages of many motorsports is that old guys (in good shape) can still do it at a respectable level, even win big races. Though I suppose I could buy some state of the art equipment, my interest is to see how fast I can get my old stuff to run with modern upgrades. If I can just be "locally-fast" and finish in the top three regularly, I'll be happy. Of course, I haven't been in a raceboat in decades, and might discover that I don't personally want to go that fast anymore, in which case I'll find a driver.

You'd like my 125. The 125cc Hydro class was very small for a long time, using Konig singles. Then in the early Seventies, some guys, notably Jim Hallum, started building engines using motorcycle engine parts. My own engine is a 1973 Yamaha air-cooled reed-valve 125MX motor. I milled off almost all of the cooling fins and welded on some water jacketing, and turned a water jacketed head. Since these are outboards, we need no radiators, the coolant being supplied by lake water being rammed into an approximately 3/16" to 1/4" diameter pickup tube in the front of the streamlined racing lower unit. Any old guys here will recall that those first-generation Yamaha reed motors had little dinky reedblocks; I modified the cylinder to take a much bigger reedblock and mounted a 34mm Konig carburetor. I rolled and welded an expansion chamber. If I knew how to post pictures (someday, not now) I could demonstrate the motorcycle engine mounted on its side to the towerhousing (that clamps the engine to the transom of the boat, and connects the powerhead to the lower unit via a shaft about 10" long), the crankshaft vertical with a rope-plate on top for starting purposes. Most of the transmission case is cut off as unnecessary (we use direct-drive, no transmission), leaving only the engine crankcase mounted with one side bolted to the towerhousing.

I never did finish this project. As a stupid young guy I wasted far too much time obssesed with puss . . . , ah . . . , with trying to get dates with young ladies. Too late I learned that the harder you try, the less successful you tend to be at that particular activity. If only I knew then what I know now, as all us old codgers mournfully tell each other. So the upshot is that I have boxes of cool mechanical project in various states of semi-completion. But this is great!! I do NOT envy the retired guys who have nothing to do but golf or go shopping with their wives and arguing about whether to buy 1-minute oatmeal or 5-minute oatmeal, you know?!!

I'm gonna have many questions for y'all about current practice in 2-stroke engine tech. Looking forward to it!!

P.S. I joined another 2--stroke site for the same purpose, and I hope any of you who go there won't mind that I will copy and paste this intro over there. I do hope to find that any competition among the various 2-stroke sites is friendly . . . .
 

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Discussion Starter #3
Having joined this site, today I found an email from a "Scott Shaeffer" (I deleted it and it may have been spelled differently) to visit him at LinkedIn, about which I know nothing.

Now I recall having met a roadracer of that name (again, spelling unknown) in the Seventies. He had one of those cool little Kawasaki 250cc race-only bikes with the water-cooled tandom cylinders. Is Scott here? I tried the Search function, using different spellings of the last name, but without result.
 

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Seattle smitty: You’re sure welcome here. Folks like you make this the best site on the net. Please send your pictures.
E2S: The place to go when you need to know :Clap:
 

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There’s a wealth of information in this site, from every perspective. They are always worth a complete read, even though you may already know the answers.
JT
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