• IninewCrow@lemmy.caEnglish
    20·
    13 days ago

    This is absolutely impressive and horrifying at the same time.

    How does the drive train even work on this thing? Or is it really just one engine powering the bike and then two just making noise to impress the crowd?

      • fartographer@lemmy.worldEnglish
        7·
        13 days ago

        That’s honestly a better solution than the two differentials I hoped for and achieves essentially the same results. I just figured I’d you’re trying to do something as silly as packing the power of 3 engines into one vehicle, creating a train of differentials that provide an output of (1+2)+3 would be far more amusing and mechanically overcomplicated.

        But I guess whoever built this was trying to be slightly more serious. But obviously not serious enough to buy a bigger engine.

        • IninewCrow@lemmy.caEnglish
          6·
          13 days ago

          I was imagining engine overheating issues … If you powered this thing for longer than ten minutes, you’d have to start moving forward to push the air over the motor to keep it cool enough … which wouldn’t be a problem for engine #1 at the front, but engine #2 would receive all the hot air from engine #1 and engine #3 would receive all the hot air from engines #1 and #2!

          Not to mention … how do you sync idle speeds and direct engine rotation for three different engines using a direct timing chain and no clutch system to deal with any differences in engine rotation?

          As silly as this all sounds … I would still love to see this thing turned on and driven down the road!

          • fartographer@lemmy.worldEnglish
            8·
            13 days ago

            If you powered this thing for longer than ten minutes, you’d have to start moving forward to push the air over the motor to keep it cool enough

            Easy enough to solve: use each idler to drive a fan. Also, large radiator. Where? Everywhere. The whole bike. Heat-resistant clothing mandatory and no shoelaces allowed!

            how do you sync idle speeds and direct engine rotation for three different engines using a direct timing chain and no clutch system to deal with any differences in engine rotation?

            You assume there’s no clutch system, but perhaps there’s no throttle system! When you start the bike, all three engines scream, locked at full throttle. The handle that would usually control throttle instead is directly tied to three clutches and your speed is determined by how engaged your clutches are.

            People will always know when you’re approaching: first they’ll hear you, then they’ll smell you, and then they’d see you.

            how do you sync idle speeds and direct engine rotation for three different engines using a direct timing chain and no clutch system to deal with any differences in engine rotation?

            *Spoken as Marisa Tomei* Positraction. I refuse to say more because whatever implementation your brain pictures is far better than any mental image I can paint with words.

            • officermike@lemmy.worldEnglish
              6·
              13 days ago

              Page title says it’s a drag racer, so I took the liberty of making the following guesses:

              • Engines aren’t running long enough to overheat
              • In the Swiss-cheese excavator bucket-looking cover is what I’m guessing is a clutch. It very well may be the case that this gets run wide open throttle and acceleration and speed are modulated with the clutch.

              All of this is just guessing. I have no first-hand experience with drag racing drivetrains, motorcycle or otherwise. I do seem to recall learning that there are automotive drag racing transmissions in which the clutches weld themselves closed during the race and need to be rebuilt between runs.

              • fartographer@lemmy.worldEnglish
                3·
                13 days ago

                Ew! Your speculations sound based on reason and research! I, on the other hand, was relying on pure stupidity.

                Personal anecdote about welding clutches: turns out it’s really easy to do! The clutch pedal fork in my '95 4Runner broke, so I ended up getting my entire clutch system replaced/rebuilt. As part of the rebuild, my mechanic’s parts supplier offered a deep discount on a racing clutch they recently started manufacturing. Somehow, this clutch sat incorrectly in the housing and presented a partial gap of a few micrometers, which the supplier assured us would be negligible within a few days. A couple of weeks later, I was running errands all day and suddenly smelled and heard something awful and couldn’t depress my clutch pedal, even when trying to stand on it. That was a fun day of abusing my clutch start override every time I stopped and wasn’t on a decline or had to change between forward and reverse!

      • officermike@lemmy.worldEnglish
        4·
        13 days ago

        I guess you’re not going to be very excited then. See my comment above for a link to more photos.

        • MrPistachiosOPEnglish
          5·
          13 days ago

          yeah sadly this was back when I first got my camera and I was more occupied with figuring out how it worked than with what I was taking a picture, I have like hundreds of photos from that day all from bad angles or with peoples butts in the frame

  • Geometrinen_Gepardi@sopuli.xyzEnglish
    3·
    13 days ago

    Why do the exhausts taper to tiny whistles? I get that a 2 stroke needs the backpressure but aren’t you limiting most of your power away with such drastic taper?

    • TerraRoot@sh.itjust.worksEnglish
      6·
      13 days ago

      The smaller it is, the more power, and the sooner you melt the piston from the retained heat/pressure.

      Don’t think of two stokes as three simple moving parts, they are one almighty pipe and a not that important engine.