Unconfigured Ad Widget

Collapse

Announcement

Collapse
No announcement yet.

Yamato 250

Collapse
X
Collapse
 
  • Page of 1
  • Filter
  • Time
  • Show
Clear All
new posts
Previous template Next
  • #1

    Yamato 250

    Can anyone help me with information for a Yamato 250 pistion port that I am restoring?

    Year? Tower housing? Timing setting? CC's?

    Does anyone have an old rear loading foot for it? Any and all information would be greatly appreciated.

    Thanks

    Steve Roskowski



    Tags: None
  • #2
    yamato 250

    I have tower and rear loaded foot along with 2 500 cc power heads and cranks, heads misc. parts.
    hshaw@hmausa.com

    Comment

    • #3
      The piston port RA never came with a rear loader. They had a vert. split with 172 allen head bolts. Also came stock with one water pick up that WILL plug with a stick and sieze one if not both pistons. Original allison CD ignition was crap, use NLA Motoplat. Pipe brackets and rings will break and fall in lake. You'll stick a piston. The clamp brackets will loosen up and the engine will dance around on transom. If you choose to nose dive at the same time, engine will leave a nice sized hole in the deck of boat. The two could be related. The heads will start to leak. Drill a hole in the bottom and top of the tower housing because the L/U to tower seal will leak and drive you nuts with water in the engine at the end of the strait, only to clean out after the turn. Water injection madatory. A Mazda bottle and pump work great, the late Allyn Stevens built a dyno to test water pumps. It's best to plumb in a constant water supply to the tank and run a overflow tube. You will need it sometime during the heat. Piston ports have a power band of 11275 rpm to 12005 rpm. Those orange velocity stacks will fall off. The crank retainer will fail and send needles through the engine. The nut will fall off the bottom of the pinion gear. When its "on" you will go about 95 mph. Two, if not three of those springs that hold the strait elbo to the curved header part will fall off. You'll get passed while leading at Depue and put a hole in the deck of your boat. Did I mention that you will sieze a piston? If a wrist pin breaks at 12000 rpm, better hope your wearing kevlar. You can lap the heads on the mirror of a Ford van between heats at a local event. At a major, you can replace piston, ring and remove aluminum from the cylinder wall. Those set screws that connect the carbs together will fall out. One of your three check valves will fail, thats OK. If two do, grab a tow rope. Thats all I can think of now.

      I hope you can see the humor in my post. Racing the piston port was exciting to say he least. I was lucky to always have a "tec" engine that belonged to Yamato. H. Kishimoto was a great engineer to work with. So was Dieter König, but thats another story.

      You cant back off for the corners, only "breath" the pipe. Have water injection finger ready. Sieze a piston, grab a tow rope.

      Fuzzy Dice hanging from the windshield help too. Join the "A" team of 1983.

      Eric Pugh
      1984 250cc APBA national champion- piston port Yamato..que song "Glory Days"
      " It's a sad day when you've outgrown everything"
      Art Pugh

      Comment

      • #4
        Wow Eric, how about some good news here.

        Are you going to break out the 125 at Depue this season?

        I was going through some old boxes and came across an old program from the Worlds in CA and old Germany photos.

        Comment

        • #5
          Originally posted by epugh66
          The piston port RA never came with a rear loader. They had a vert. split with 172 allen head bolts. Also came stock with one water pick up that WILL plug with a stick and sieze one if not both pistons. Original allison CD ignition was crap, use NLA Motoplat. Pipe brackets and rings will break and fall in lake. You'll stick a piston. The clamp brackets will loosen up and the engine will dance around on transom. If you choose to nose dive at the same time, engine will leave a nice sized hole in the deck of boat. The two could be related. The heads will start to leak. Drill a hole in the bottom and top of the tower housing because the L/U to tower seal will leak and drive you nuts with water in the engine at the end of the strait, only to clean out after the turn. Water injection madatory. A Mazda bottle and pump work great, the late Allyn Stevens built a dyno to test water pumps. It's best to plumb in a constant water supply to the tank and run a overflow tube. You will need it sometime during the heat. Piston ports have a power band of 11275 rpm to 12005 rpm. Those orange velocity stacks will fall off. The crank retainer will fail and send needles through the engine. The nut will fall off the bottom of the pinion gear. When its "on" you will go about 95 mph. Two, if not three of those springs that hold the strait elbo to the curved header part will fall off. You'll get passed while leading at Depue and put a hole in the deck of your boat. Did I mention that you will sieze a piston? If a wrist pin breaks at 12000 rpm, better hope your wearing kevlar. You can lap the heads on the mirror of a Ford van between heats at a local event. At a major, you can replace piston, ring and remove aluminum from the cylinder wall. Those set screws that connect the carbs together will fall out. One of your three check valves will fail, thats OK. If two do, grab a tow rope. Thats all I can think of now.

          I hope you can see the humor in my post. Racing the piston port was exciting to say he least. I was lucky to always have a "tec" engine that belonged to Yamato. H. Kishimoto was a great engineer to work with. So was Dieter König, but thats another story.

          You cant back off for the corners, only "breath" the pipe. Have water injection finger ready. Sieze a piston, grab a tow rope.

          Fuzzy Dice hanging from the windshield help too. Join the "A" team of 1983.

          Eric Pugh
          1984 250cc APBA national champion- piston port Yamato..que song "Glory Days"

          Eric,

          Quit giving us the run around and tell us how you really feel.


          j/k As I did enjoy your story.


          Mike
          Sattler Racing R-15
          350cc Pro Alcohol Hydro
          TEAM VRP
          The Original "Lunatic Fringe"

          Spokane Appraiser

          Comment

          • #6
            Eric,

            Did I miss the part about the cranks breaking or having to trick new people into starting it because it's bitten all of your normal help and they won't get anywhere near it?

            Dave
            I always thought growing up would be cool, I was wrong!
            The other day GG laughed at me because I take more pills a day than she does....

            Comment

            • #7
              Originally posted by Dave_E71
              Eric,

              Did I miss the part about the cranks breaking or having to trick new people into starting it because it's bitten all of your normal help and they won't get anywhere near it?

              Dave
              Sissy's, Real men don't get bit. Even gary isnt afraid of the 1100 Yamaha!
              real men!

              Comment

              Previous template Next
              Working...
              X