Who else loves two strokes?

[Megalodon]

OOH!!! Thanks Meg. That new 9.9 hp Merc hasn't been used yet! It will love you.

I'll be happy to bring it every time. Let's give the new baby a good start!

Does the owner's manual recommend any additive? Yamaha, for example recommends the use of "ring-free"; perhaps Mercury sells the same stuff under a different name?

 

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[Megalodon]

Cool, many years ago I had that same Engine in a 10 Ft. john boat

The 9.9 is a bargain among small outboards. The unusual decimal designation came about to meet regulations for some reservoirs that limited outboard size to "under 10 hp". In the old days, the only difference between the 15 and the 9.9 was the decal on the cowling. Later, some had a slightly smaller carb but the same displacement.

On a bigger boat, and with a long shaft, it is an excellent trolling motor or crab trotline runner and better than running a big outboard at low RPMs for hours at a time.

 

[Megalodon]

93 octane No ethanol is ALL Ive ever run in my baby, and a drop of Av-gas or 104 octane booster just for the Smell of it . Not that it needs it......I do View attachment 1765936

Is that a Cobra?

 

[Charlie P. (NY)]

My first motorcycle was a one-lunger Kawasaki 350cc Bighorn single cylinder. Beat the crap out of me at highway speeds, but 0 to 40 mph was before you could blink. Wish I still had it.

Now my 2-strokes are a Mercury 5Hp outboard (bulletproof), a Husqvarna 353-e chainsaw that heats my home, a Toro snowblower, a Husqvarna 28cc weed trimmer and several 26cc to 43cc engines in my R/C airplanes. This one has a 33cc Fuji 2-stroke engine (6'10" wingspan).

 

[Blak bart]

Me....I love 2xs......94ccs......36 inch bar in an alaskan chain saw mill. High RPMs and lots of saw dust = beautiful flame mahogany slabs. beautiful flame mahogany is an urban loggers dream and big $$$....treasure !!

 

[alaskaseeker]

No one....

 

[Charlie P. (NY)]

I never used ethanol gas in my boat. My mechanic said NEVER use it.

Ethanol is bad news for the older diaphragm pump carburetors and flexible fuel lines. Since 2017 or so the materials used in replacement kits can take it, but it eats the older fuel lines and synthetic "rubber" components. I get ethanol free (93 octane) at a local station for my 2-strokes and my 1956 (leaded gas) tractor. I add a shot of Marvel to the latter when I add gas.

 

[San Antone]

Flew fixed wing ultralights and powered parachutes with Rotax 2 stroke engines for years and loved them;
447, 503 and the 582 engines.

 

[Megalodon]

Ethanol is bad news for the older diaphragm pump carburetors and flexible fuel lines. Since 2017 or so the materials used in replacement kits can take it, but it eats the older fuel lines and synthetic "rubber" components. I get ethanol free (93 octane) at a local station for my 2-strokes and my 1956 (leaded gas) tractor. I add a shot of Marvel to the latter when I add gas.

The ethanol also destroys the o-rings and seals. The biggest problems I've seen are with phase separation, when the ethanol attracts water from the atmosphere. When phase separation occurs, the goo leads to corrosion in the fuel tanks. Oxidation on the inside of aluminum tanks is sloughed off the inside of the tanks and the aluminum particles are passed down to the engines. The small high-pressure fuel filters get clogged with gray aluminum particles. By the time a boater notices this (usually by poor performance leading to investigation of the cause), it is evidence that the built-in fuel tank needs to be replaced, along with all the lines. Not all boats, even the highest end models, have access panels to change the fuel tank, so the floors need to be cut out. Adding a separate fuel-water separator is a must if one has to use gasoline with ethanol. Fuel lines delaminate when exposed to the ethanol and add to the problems with the tanks. Older fiberglass fuel tanks experience breakdown of the resins when exposed to ethanol, passing the resin particles down to the engine. Such tanks get "soft" and also need to be replaced. Good quality roto-molded plastic tanks are probably best.

One reason why we have not noticed more catastrophic failures with our cars and trucks is that they are used much more often than boats that sit on trailers or on the water - with fuel tanks vented to the atmosphere. The boat tank vents were always intended to be part of safety features to reduce ignition of fuel vapors below deck, but now the vents are a route for the water in air to combine with a hygroscopic solvent such as ethanol.

I have been boating for parts of seven decades, and if I did not have access to ethanol-free fuel, I would switch to electric motors or stick to my kayaks.

When ethanol was mandated, it was a cynical decision to buy votes in the corn states despite known problems with adding this solvent to the nation's fuel supply. Shame on them for voting to sacrifice our fuel supply for re-election.

 

[IMAUDIGGER]

Agreed. I'm afraid they have started something that will never end due to the political cycle.

So much for capitalism.

 

[islamoradamark]

I still got my 1999 yomama ha 2 stroke on my boat lots of smoke keeps da skeeters away

 

[jewelerguy]

when I was a kid my Dad had a '73 Yamaha RD350. It was a cool bike. My first bike was a '74 Kawasaki KS 125. I loved that bike and even still miss it's on/off road ability today. Once in a while it would get a piece of carbon wedged in the spark plug gap causing it to die, so you'd have to stop and pull the plug and clean it to continue on your way. I still love motorcycles and now I ride a Kawasaki 1700 Nomad. Not a two stroke of course, but my love of riding all started from that little 125

 

[dsrtdwg1]

During the seventies I owned a series of r5/rd350/rd400 yamahas. Also rode lots of friends kaw 500/750 triples. Anyone who has ever ridden a ported/piped/larger carb 2 stroke knows the absolute thrill of a high strung FAST LIGHTWEIGHT row through the gears nonstop motorcycle. Anyone who ever owned such beasts also learned very quickly how to do top ends.

 

[Sidevalve45]

I had a 380 Suzuki and a H2 750 Kawasaki. Both two stroke triples. The Kawasaki was a rocket! I had that thing up to 115 mph once and it was still pulling hard. My favorite two stroke was a 1966 175 Bridgestone Dual Twin. It was a great running bike and was pretty quick for it's size. This is my favorite ride these days. 74 cubic inch flat head

 

[Carl-NC]

I had a 1970 Bridgestone 200 MkII, fun little bike. Then went straight to a 1973 Suzuki GT750, man that was a rocket. Dad had bought it with a locked-up engine to give me something to do, I rebuilt it and then to his regret I started riding it. It's a wonder I didn't kill myself, I was only 15.

Later in life I picked up a '75 GT750 but it just wasn't the same... the '73 had 32mm Mikuni slide needle carbs that had wicked-fast response, in later models Suzuki toned it down a bit. I'd buy another '73 if the price is right.

 

[Mudflap]

Nothing like the smell of my old RT-1, 360 with kit carb and tuned exhaust cranking 53 Hp and burning that super smellin Castrol !!! (Not too sure how I survived that bike!!!)

On the 2 stroke scene, Echo and several others warrant their equipment for 5 years, however the small print sez excluding any fuel problems.... That ethanol just flat eats the fuel systems. I find that Stabil or Stabil Marine doesn't seem to work any more. I use 100 octane and buy fuel in small quantities add the Stabil. Used to be able to use Stabil and fill tank to full to remove air and I could sit use it the next season. Not any more. Any more I just run em dry. Start W/new fuel next year.

 

[chub]

The 350 triple had fixed footpegs (yikes) and thin forks and a drum front brake.....didnt really matter what the front brake was as the front wheel wasnt on the ground that much anyway
I used almost as much oil as fuel... felt like it at times . Points and coil ignition. One time I stopped to gas up and realised that two exhaust baffles had rattled loose and shaken out. The neighbour up the road asked me to not drive past his house because it woke the baby up

I do watch twostrokestuffing on youtube. Also LOVE Hotsaws and all racing chainsaws. Also have a big soft spot for those old vintage McCullough powered 60's go karts.

Chub

 

[wainzoid]

There is one of those old yellow McCullough go kart motors in Dads Garage. He used to race almost every day of the week. Every town had a track. With the work he had done to it, I think it turned like 21,000 rpm. Once he quit racing I had alot of fun with it on the hiway. Could only ride it for 20 mins or so, then had to put it away because the cops would soon be looking for it.

 

[Carl-NC]

There is one of those old yellow McCullough go kart motors in Dads Garage.

That brings back more 2-stroke memories. My best friend had a kart with a McCulloch engine, don't recall the model. I also had a kart but with a Briggs. I wanted More Power. Dad was a McCulloch dealer and had an old Mac 15 chainsaw collecting dust, so I converted it into a kart engine. Had to turn down the saw sprocket on a lathe, then braze a #35 sprocket on the clutch drum. It worked, and worked pretty good, but not nearly the oomph my friend had in his factory kart engine. I think we could get his close to 50mph, and when you're 6" off the ground that's pretty fast.

 

[Carl-NC]

Here's my '75 GT750: