Oddball engines and prototypes

[Pursang]

Oddball engine - amazing story!

[F5 Dave]

I watched that day before. Very Once over lightly.

Love Speed and Loss is a ore complete story, and then is the book Kim.

[katinas]

Interesting engine upgrades of EFI 2024 KTM 250. Brand new cylinder with reduced scavenging ducts.

[katinas]

Honda NSR 500 crankcase oil slots are arranged in an interesting way.
Crankcase coud be from 88 to 90 NSR 500 (or from 91 with different left side cover) as intake side studs placment is narrower and vertical reed cage position used before BigBang.

[husaberg]

Interesting is def an earlier version with the sideways intakes ala NSR250. Lawson ish period
Those orings in place of base gaskets seem like a bloody good idea.



The later ones are very conventional.

[katinas]

Earlier versions of 112 angle from 1987 to 1991, can be recognized by under engine water pump, unit crank and vertical side by side reed cages. Only 1990 model carbs positioned in skew way. But easiest way to recognize year is the engine left side gear cover, as they all different from 1987 to 1991 (89 and 90 just different colours).

[katinas]

Since 1991, an additional lower radiator has been used, but very ineresting that one of the Garder's 87 NSR 500 was equipped with additional radiator.

[pete376403]

Stolen from Facebook - Here's an engine rarely seen since they were intended to be disposable. This is the 4 cylinder radial engine from a WWII German G7A torpedo. It ran on Decaline fuel (decahydronaphthalene), which was first burned using compressed air (stored in a tank onboard) as an oxidizer. The combustion byproducts were then passed through a device called a 'wet heater', which also introduced water (from a 57L storage tank) to produce superheated steam. This high pressure mixture of superheated steam and compressed air was finally sent through the engine to drive the pistons.
Since the entire internal combustion/steam generator system was self-contained inside the hull of the torpedo, it could run underwater. The 4 cylinder, 'X' type radial engine produced up to 350 horsepower at its maximum power setting, which was enough to push the 26' (just over 7 meters) torpedo (the length of a large Uhaul moving van here in the States for comparison purposes) along at nearly 50mph while submerged.

[husaberg]

Around 90-91 Honda changed the crank from a 90 even fire to a two up two down this was to replicated the Yamaha .It made it more rideable this was later refined to firing all under 90 degees. ie big bang . 1992? The configuration Dohan returned to when he got bored after the unleaded fuel came in was the two up. the big bang needed a balance shaft af the engine was drove through the center to the jackshaft.
even when it was reverted the two up (ie screamer) they retained the balance shafted as it lessened the gyro making it turn easier. Not sure if this was the balance shaft or the fact it reversed the engine direction but likely both

[F5 Dave]

It sure sounded good from bottom of Lukey when he span it out of there. Marvellous stuff.

[husaberg]

edit it looks like pre big bang already had a jackshaft for reduced gyro.

[jato]

88 was the 90 degree firing - it had weird sound as you would expect. watching it exiting corners it seemed to give away a bike length or two compared to the 180 degree bikes (everyone else?) does anyone know for certain when the nsr first had a backward turning crank?

[katinas]

Not sure, but try to list in short way, just the main changes through the years, without obscured test models.

1981 - 1983 NS 500 V3 112 deg. symetrical 1-3-2 firing every 120 deg. - with long jackshaft, crank turning backward.

1984 NSR 500 V4 90 deg. symetrical 1-4-3-2 firing every 90 deg. - with long jackshaft, crank turning backward.

1985 - 1986 V 90 deg. symetrical 1-2-3-4 firing every 90 deg. - without jackshaft, crank turning forward.

1987-1989 V 112 deg. symetrical 1-4-3-2 firing every 90 deg. - with long jackshaft, crank turning backward.

1989/1990-1991 V 112 deg. symetrical paired 1.2-3.4 firing every 180 deg. - with long jackshaft, crank turning backward.

1992-1996 V 112 deg. big bang paired 1.3-2.4 firing 68 deg. two cranks connected to short jackshaft from center, crank turning backward.

1997-2002 V 112 deg symetrical paired 1.3-2.4 firing every 180 deg two cranks connected to short jackshaft from center, crank turning backward.

[katinas]

Stolen from Facebook - Here's an engine rarely seen since they were intended to be disposable. This is the 4 cylinder radial engine from a WWII German G7A torpedo. It ran on Decaline fuel (decahydronaphthalene), which was first burned using compressed air (stored in a tank onboard) as an oxidizer. The combustion byproducts were then passed through a device called a 'wet heater', which also introduced water (from a 57L storage tank) to produce superheated steam. This high pressure mixture of superheated steam and compressed air was finally sent through the engine to drive the pistons.
Since the entire internal combustion/steam generator system was self-contained inside the hull of the torpedo, it could run underwater. The 4 cylinder, 'X' type radial engine produced up to 350 horsepower at its maximum power setting, which was enough to push the 26' (just over 7 meters) torpedo (the length of a large Uhaul moving van here in the States for comparison purposes) along at nearly 50mph while submerged.

Found such old drawings of a torpedo engine. Very interesting two in one valve configuration

[Pursang]

Interesting engine upgrades of EFI 2024 KTM 250. Brand new cylinder with reduced scavenging ducts.

Perhaps trying to maximize bottom end power for stadium Superenduro ???