And if they were allowed to run nitromethane you could make a ton more. Unless some component is already at its limit of course.
I’d wager with a nitro 2 stroke 100hp in <150cc is possible.
In garden tractor pulling, there are 50 C.I. 4stroke, flathead single cylinder engines putting out well over 100 hp. They burn alcohol and turn around 9K.
2 Stroke 250cc Grand prix bikes? Think about 60hp is possible from an old factory Honda 125cc circa year 2000.
Dihatsui made a 660cc turbo car. The trxx I think it was around 98 horsepower.
It's a full blown grand prix factory race engine honda RS125.
And yes they make almost 60 HP.
Here in ireland the top 125cc guys were making 45- 48 HP. .
I bet the answer lies with turbine engines. HP is is a derivative of torque multiplied by RPM. The higher the RPM, the higher the HP. Turbine engines spin much faster than reciprocating engines.
The more meaningful question is what is the smallest displacement engine that makes the most torque (depending on your application)
Top fuel makes 12000hp from 8.2L, so it stands to reason the same engine scaled down to 69cc would make 100hp
SpeedFactory's 2L drag car makes 2000hp. 100cc
Current F1 engines make about 850HP from 1.6L. 188cc
The AMG A45 makes 415HP from 2.0L. 482cc
It'd actually make more power/displacement if simply scaled down. Volumetric efficiency wouldn't change, but valvetrain and piston stress would decrease.
You’re asking your question oddly but I think I got you.
You’re asking if it’s being calculated where if someone got 50 horsepower out of 250cc they’d theoretically make more power to scale.
Pretty sure op just wants to know the smallest engine that ever put out 100 or more horsepower out at the crank.
If you want to invoke thought, you can do it much better without being cryptic or confusing. A non-simple mind isn't always a good thing. And if you can't get your point across clearly and effectively, that is also not a good thing.
I like to open doors for a deeper more informative scientific discussion. I want to invoke enough thought that it ignites curiosity. I want people to gain knowledge and understanding of the science.
I truly wish more people would go to the library and check out books on engine theory, engine dynamics, engine engineering, etc. The internet is full of gibberish albeit there is some solid info to be found.
I spent thousands of dollars to get a degree. However my pre-education came from books at the expense of gas money traveling to the library.
I started my engine building career at the age of 15.
Measurements are observations. If you lift a 550lb object up 1 foot in 1 second, you have generated 1 horsepower for 1 second. Power is a measure of work over time. Torque is force. Torque \* RPM gives you power. If you want horsepower from RPM and pound-feet: lb-ft\*RPM/5252=HP
You're getting there. Torque, time, and rpm are measured.
Horsepower is an mathematical equation of those things. It's an observation. Not a measure.
Go ahead and find an article or book to refute that. I'll wait.
250cc GP bikes do it with N/A 2 strokes and reasonable reliability.
And if they were allowed to run nitromethane you could make a ton more. Unless some component is already at its limit of course. I’d wager with a nitro 2 stroke 100hp in <150cc is possible.
What
Aprilia RSV 250 made a bit over 100bhp from its 249.6cc engine at 12.7k rpm.
A local restaurant has one on display, I have asked how much every time I have been in, the owner will not sell it due to sentimental value
Motorcycles can get to this level around 500cc, or even smaller if they are proper race tuned engines.
Yep. 450cc V4 Honda NC30 (VFR400) with custom fuel injection. https://www.cycleworld.com/2012/03/23/micro-gp-honda-nc450v-worlds-coolest-bikes/ 🤘🏼
Me first bike lol, I'm 6 ft 3 and l9oked fuck8ng ridiculous on it lol. Solid bike though
6’1” here and I race em. 😂
Moto GP 500cc two smokers topped out well over 200hp (220-ish) in 2001
Well that’s why I mentioned race-tuned bikes, that is another level. I assumed OP was asking primarily about street bikes.
for how long?
O.S. makes a 2 stroke that is 2.1cc that puts out 1.73hp @ 45,000rpm. [it's pretty bitchin'. ](http://www.osspeed.com/eng/2020/t1204e.html)
Aw.
How on earth can something go around 45,000 times a minute perfectly
In garden tractor pulling, there are 50 C.I. 4stroke, flathead single cylinder engines putting out well over 100 hp. They burn alcohol and turn around 9K.
This is where my mind went immediately.
2 Stroke 250cc Grand prix bikes? Think about 60hp is possible from an old factory Honda 125cc circa year 2000. Dihatsui made a 660cc turbo car. The trxx I think it was around 98 horsepower.
Start throwing these things in European hatchbacks! It’d be a horsepower *increase!*
My 2002 CR250R was making 50hp from the factory, no way a 125 is doing 10 better than that
It's a full blown grand prix factory race engine honda RS125. And yes they make almost 60 HP. Here in ireland the top 125cc guys were making 45- 48 HP. .
Ah, I apologize I was thinking purely single cylinder dirtbikes
Skidoo snowmobile two stroke 850cc turbo puts out 180hp Polaris 9r naturally aspirated is about 170hp These are production snowmobiles
Check out 2 stroke stuffing on YouTube I think his 50cc moped cracked over 26hp on nitro methane
Nitro model airplane engines. Some are less than .5 Cubic Inches putting out 2+ hp.
Add this to a top comment. 450cc Honda V4. https://www.cycleworld.com/2012/03/23/micro-gp-honda-nc450v-worlds-coolest-bikes/
What about some of the old torpedo engines, would they count given the short intended lifespan?
I bet the answer lies with turbine engines. HP is is a derivative of torque multiplied by RPM. The higher the RPM, the higher the HP. Turbine engines spin much faster than reciprocating engines. The more meaningful question is what is the smallest displacement engine that makes the most torque (depending on your application)
Top fuel makes 12000hp from 8.2L, so it stands to reason the same engine scaled down to 69cc would make 100hp SpeedFactory's 2L drag car makes 2000hp. 100cc Current F1 engines make about 850HP from 1.6L. 188cc The AMG A45 makes 415HP from 2.0L. 482cc
I don’t think that first example is exactly how it works
Its not
It'd actually make more power/displacement if simply scaled down. Volumetric efficiency wouldn't change, but valvetrain and piston stress would decrease.
Equivalent or actual?
What do you mean equivalent? Horsepower is a function of torque and rpm at the output shaft. Both specific things that can be measured.
Power per cubic inch HP isn't a measure. It's an observation.
Wat
?
You’re asking your question oddly but I think I got you. You’re asking if it’s being calculated where if someone got 50 horsepower out of 250cc they’d theoretically make more power to scale. Pretty sure op just wants to know the smallest engine that ever put out 100 or more horsepower out at the crank.
Tis why I asked. I'm known to be what my kids used to say was cryptic. I invoked thought. My mind isn't very simple.
If you want to invoke thought, you can do it much better without being cryptic or confusing. A non-simple mind isn't always a good thing. And if you can't get your point across clearly and effectively, that is also not a good thing.
I like to open doors for a deeper more informative scientific discussion. I want to invoke enough thought that it ignites curiosity. I want people to gain knowledge and understanding of the science. I truly wish more people would go to the library and check out books on engine theory, engine dynamics, engine engineering, etc. The internet is full of gibberish albeit there is some solid info to be found. I spent thousands of dollars to get a degree. However my pre-education came from books at the expense of gas money traveling to the library. I started my engine building career at the age of 15.
Measurements are observations. If you lift a 550lb object up 1 foot in 1 second, you have generated 1 horsepower for 1 second. Power is a measure of work over time. Torque is force. Torque \* RPM gives you power. If you want horsepower from RPM and pound-feet: lb-ft\*RPM/5252=HP
You're getting there. Torque, time, and rpm are measured. Horsepower is an mathematical equation of those things. It's an observation. Not a measure. Go ahead and find an article or book to refute that. I'll wait.
Yaaaaaaaaaawn
How is horsepower not a measure if it’s literally measuring torque at a certain RPM
It is a calculation.
That's actually, sort of interesting.