Ask Lemmy
A Fediverse community for open-ended, thought provoking questions
Rules: (interactive)
1) Be nice and; have fun
Doxxing, trolling, sealioning, racism, and toxicity are not welcomed in AskLemmy. Remember what your mother said: if you can't say something nice, don't say anything at all. In addition, the site-wide Lemmy.world terms of service also apply here. Please familiarize yourself with them
2) All posts must end with a '?'
This is sort of like Jeopardy. Please phrase all post titles in the form of a proper question ending with ?
3) No spam
Please do not flood the community with nonsense. Actual suspected spammers will be banned on site. No astroturfing.
4) NSFW is okay, within reason
Just remember to tag posts with either a content warning or a [NSFW] tag. Overtly sexual posts are not allowed, please direct them to either [email protected] or [email protected].
NSFW comments should be restricted to posts tagged [NSFW].
5) This is not a support community.
It is not a place for 'how do I?', type questions.
If you have any questions regarding the site itself or would like to report a community, please direct them to Lemmy.world Support or email [email protected]. For other questions check our partnered communities list, or use the search function.
6) No US Politics.
Please don't post about current US Politics. If you need to do this, try [email protected] or [email protected]
Reminder: The terms of service apply here too.
Partnered Communities:
Logo design credit goes to: tubbadu
view the rest of the comments
Constant velocity carburetors blew my mind when I learned how they worked, and I got the funniest introduction to them.
I had an Aprilia RS-50 motorcycle which had a slide-type carburetor. Instead of a coin-in-a-pipe throttle, this thing basically had a portcullis across the intake. Pulling on the throttle cable pulled the slide upwards making the aperture/venturi larger, allowing in more air, while also lifting a needle up out of the jet to allow more fuel in. It's a 2-stroke race bike, so you could easily bog down the engine if you opened the throttle too fast.
Then I bought a Ninja 250F, which has constant velocity carbs. Which also have a slide, AND a butterfly valve. The butterfly valve is operated by the throttle cable to control power. The slide is vacuum powered from the engine, and opens and closes the venturi to keep the air velocity through the carburetor constant, in order to keep the suction at the jet constant. It also has a needle in the main jet which it lifts along with the slide, so the needle's taper meters the fuel mixture for the amount of air going through the carb. This inherently compensates for air density; if the air is less dense the vacuum mechanism can't pull the slide open as far so the slide doesn't open as far, and neither does the needle valve. So it automatically maintains the mixture.
Which is why using constant velocity carburetors on the Rotax 912 engine is such a brilliant idea. A carbureted airplane engine with no cockpit mixture control.
RS50 is such a fun bike, and I know the pain with the carb, I have to ride mine uphill, also, just replaced the 12mm flat slide carb with a 17.5mm round slide, runs quite nice
I had one of the very few of them in North America. I don't think they ever imported them at any great scale. I bought mine used, and it was obviously used as a track bike. It had a cylinder kit that took it up to about 72cc, the damn thing could do 70.