4 ms·

If they can keep the size/weight, go to 5 HP AND make it cheap, this would be perfect for chainsaws, brush cutters/trimmers, blowers, and lots of other portable

If they can keep the size/weight, go to 5 HP AND make it cheap, this would be perfect for chainsaws, brush cutters/trimmers, blowers, and lots of other portable gas-powered tools... Hell, even small portable generators. The problem I see is that existing engines are already good enough and cheap, so it could be a hard sell for manufacturers.

Shivetya 10y ago
I wonder how loud it is compared to traditional engines
- karmakaze 10y ago
  "the X2 engine is exceptionally quiet because it burns all of its fuel. In current ICE engines, an alarming amount of fuel goes out the tailpipe. This not only cuts down on fuel efficiency and pollutes the air, it also makes the engine noisy. Since the X2 engine burns its fuel completely, there’s no need for complicated silencing apparatus. (Update: The engine runs quietly due to not needing poppet valves.)"[0] [0] http://www.gizmag.com/liquidpistol-rotary/24623/ http://www.gizmag.com/liquidpistol-rotary/24623/
  - DrScump 10y ago
    If true, that would also cut emissions significantly compared to a conventional 2-stroke.
  - ChuckMcM 10y ago
    The challenge with that comment from 2012, is that the go cart video from 2016 is pretty noisy. Easily 90 to 100db from the sound on the video. https://vimeo.com/170502635 https://vimeo.com/170502635
  - userbinator 10y ago
    In current ICE engines, an alarming amount of fuel goes out the tailpipe. This not only cuts down on fuel efficiency and pollutes the air, it also makes the engine noisy. The "an alarming amount of fuel goes out the tailpipe" is reminiscent of the wording associated with various fuel-saver scam gadgets. In practice, this is measured in HC emissions, which are usually in the low tens of PPM range on a properly tuned engine. Disregarding mechanical sources, engine noise is largely caused by the high-pressure gases flowing out the exhaust with pulsations on each power stroke. The distinctive beating of a low-cylinder-count engine e.g. a motorcycle is entirely this phenomenon. To attribute the noise of a properly functioning (i.e. not backfiring) engine to "unburned fuel" is completely wrong.
    - karmakaze 10y ago
      I questioned whether should edit part of that out. Somewhere it does mention over-expansion to near 1 atmosphere in its cycle. So the theory is quiet, the go kart audio not withstanding.
    - kbob 10y ago
      A four-stroke engine fires every other crankshaft revolution. Each cylinder creates its own pulses. The exhaust manifold tries, with varying success, to blend those into a single higher-frequency pulse train. The Liquid rotary fires thrice per revolution, or six times faster. The go-kart engine is designed for 10,000 RPM. That puts its fundamental frequency at a less objectionable 500 Hz. But the go-kart video did not sound like 500 Hz -- it sounded like about 100 Hz. As for the "alarming amount of fuel out the tailpipe" line, maybe they're comparing a two-stroke engine. I don't really know how unburned fuel affects a two-stroke's sound.
sunstone 10y ago
The weight of smallish outboard motors (9.9hhp in particular) is really irritating. Making these a lot lighter for the same power would find a customer with me.
Obi_Juan_Kenobi 10y ago
Based on their video (last on this page), that certainly looks like their target: http://liquidpiston.com/technology/x-mini-gasoline/ http://liquidpiston.com/technology/x-mini-gasoline/ If these are indeed quieter, then I could see them commanding a significant premium for lawn tools, generators, etc.

Shivetya 10y ago

I wonder how loud it is compared to traditional engines

karmakaze 10y ago
"the X2 engine is exceptionally quiet because it burns all of its fuel. In current ICE engines, an alarming amount of fuel goes out the tailpipe. This not only cuts down on fuel efficiency and pollutes the air, it also makes the engine noisy. Since the X2 engine burns its fuel completely, there’s no need for complicated silencing apparatus. (Update: The engine runs quietly due to not needing poppet valves.)"[0] [0] http://www.gizmag.com/liquidpistol-rotary/24623/ http://www.gizmag.com/liquidpistol-rotary/24623/
- DrScump 10y ago
  If true, that would also cut emissions significantly compared to a conventional 2-stroke.
- ChuckMcM 10y ago
  The challenge with that comment from 2012, is that the go cart video from 2016 is pretty noisy. Easily 90 to 100db from the sound on the video. https://vimeo.com/170502635 https://vimeo.com/170502635
- userbinator 10y ago
  In current ICE engines, an alarming amount of fuel goes out the tailpipe. This not only cuts down on fuel efficiency and pollutes the air, it also makes the engine noisy. The "an alarming amount of fuel goes out the tailpipe" is reminiscent of the wording associated with various fuel-saver scam gadgets. In practice, this is measured in HC emissions, which are usually in the low tens of PPM range on a properly tuned engine. Disregarding mechanical sources, engine noise is largely caused by the high-pressure gases flowing out the exhaust with pulsations on each power stroke. The distinctive beating of a low-cylinder-count engine e.g. a motorcycle is entirely this phenomenon. To attribute the noise of a properly functioning (i.e. not backfiring) engine to "unburned fuel" is completely wrong.
  - karmakaze 10y ago
    I questioned whether should edit part of that out. Somewhere it does mention over-expansion to near 1 atmosphere in its cycle. So the theory is quiet, the go kart audio not withstanding.
  - kbob 10y ago
    A four-stroke engine fires every other crankshaft revolution. Each cylinder creates its own pulses. The exhaust manifold tries, with varying success, to blend those into a single higher-frequency pulse train. The Liquid rotary fires thrice per revolution, or six times faster. The go-kart engine is designed for 10,000 RPM. That puts its fundamental frequency at a less objectionable 500 Hz. But the go-kart video did not sound like 500 Hz -- it sounded like about 100 Hz. As for the "alarming amount of fuel out the tailpipe" line, maybe they're comparing a two-stroke engine. I don't really know how unburned fuel affects a two-stroke's sound.

sunstone 10y ago

The weight of smallish outboard motors (9.9hhp in particular) is really irritating. Making these a lot lighter for the same power would find a customer with me.

Obi_Juan_Kenobi 10y ago

Based on their video (last on this page), that certainly looks like their target: http://liquidpiston.com/technology/x-mini-gasoline/ http://liquidpiston.com/technology/x-mini-gasoline/ If these are indeed quieter, then I could see them commanding a significant premium for lawn tools, generators, etc.