026 Dyno Test

[Evan]

4.2 horse. now that would be one heck of 50cc saw. thats 60cc territory. hows it maintain tourque in the cut.

 

[mountainlake]

The equasion is: HP=T X RPM/5252. What this means is that with any engine, HP will always be less than T below 5252 RPM. HP will always be greater than T above 5252 RPM. HP will exactly equal T at 5252 RPM. This, of course assumes we are referring to the scalar quantities as referenced to Torque measured in ft.lb.

Quite a few engines don't turn 5252 Rpm, big diesels somewhere around 2000 max, they make max hp around 2000 rpm and max torque around 1300 to 1600 rpm some are over 1500 ft lbs now. Steve

 

[eyolf]

4 hp for 50 cc's isn't really all that much.

<a href="http://www.herdan.com/engines/">Here's a link</a> to a company selling an air-cooled 50cc moped engine that cranks out 9 hp, and a water-cooled model that provides 11. Right now their market seems to be serious moped and scooter riders that want more power.

I don't think one could get much past that with a can muffler, unless you were willing to put up with really short engine life. I used to know a guy who raced Karts and eventually gave it up as too expensive...even a karter in a conservative class will be rebuilding his engine several times in a season.

I saw one of the 6hp Morini models on a bicycle last year. Scary fast on a bike with crappy tires, no suspension, and too steep rake to handle well. But then, I'm on the sundown side of 50.

Thanks for the kind words, John.

 

[mountainlake]

Where is this 4.2 hp coming from? I only see 3.25 max on the number chart and about the same on the graph. Steve

 

[tdi-rick]

Quite a few engines don't turn 5252 Rpm, big diesels somewhere around 2000 max, they make max hp around 2000 rpm and max torque around 1300 to 1600 rpm some are over 1500 ft lbs now. Steve

Not sure what your point is.

The quote you reference is in response to how horespower is calculated from measured torque. Regardless of whether an engine can achieve 5252RPM or not is immaterial to how torque and HP is measured and calculated, and torque and HP will always be equal at 5252RPM, regardless of whether an engine can actually rotate the crank at that speed or not.

 

[AUSSIE1]

Not sure what your point is.

The quote you reference is in response to how horespower is calculated from measured torque. Regardless of whether an engine can achieve 5252RPM or not is immaterial to how torque and HP is measured and calculated, and torque and HP will always be equal at 5252RPM, regardless of whether an engine can actually rotate the crank at that speed or not.

Yeah I agree and the 5252RPM crossover has always been fascinating.

Pushing power into higher RPM results in a narrower power "band".
The way around this is with variable inlet/outlet timing/profiles.

Another way to deal with the high rpm narrow band was to run heavier rotating mass.

 

[maico490]

Yeah I agree and the 5252RPM crossover has always been fascinating.

Only if you use your quaint old fashioned way of measuring things. Having said that I still like hp over kW. Easier to visualize somehow.

 

[Gypo Logger]

Lambert sent me the picture of the bass again, if I could just
figure out how to crop that woman out of the picture I would
be happy. I knew Steve was probably an engineer, just trying to
figure out what denomination. I majored in Physics myself, along
with a half of a dozen other majors, but was too drunk and
horny to learn much. I like a good post though, Ol Walt is a
champ in that dept as well.
Fish

Probably your most provocative post yet Fish. They can say what they want about you John, but at least you're consistant. Maybe we can get Ole Ken back on here and those other Lackies.
John

 

[AUSSIE1]

Only if you use your quaint old fashioned way of measuring things. Having said that I still like hp over kW. Easier to visualize somehow.

But that's me. Quaint and old fashioned.

 

[Fish]

Probably your most provocative post yet Fish. They can say what they want about you John, but at least you're consistant. Maybe we can get Ole Ken back on here and those other Lackies.
John

Well, not really, I now find Llamas quite repulsive, but an Alpaca in a thong,
well, that is another thread altogether........

 

[mountainlake]

2.3 hp for the stock saw, something wrong with either the saw or the dyno. Steve

 

[timberwolf]

Old thread, but a good one.

No one cuts at 14000 rpms. My Husky is rated at 9000 I believe

Hmmm. http://www.youtube.com/watch?v=hDyko6rBQM0

Here is a stock appearing 026 on gas that should be pushing very close to 9hp @ 13,500 - 14,000 RPM in the wood. This 026 has a leg up on a stock 088 with equal chain and even with 088 running taller gear to even chain speed out.

The numbers on John's dyno charts seam to drop off a little quicker than I would think the should at higher RPM.

 

[Gypo Logger]

Old thread, but a good one.



Hmmm. http://www.youtube.com/watch?v=hDyko6rBQM0

Here is a stock appearing 026 on gas that should be pushing very close to 9hp @ 13,500 - 14,000 RPM in the wood. This 026 has a leg up on a stock 088 with equal chain and even with 088 running taller gear to even chain speed out.

The numbers on John's dyno charts seam to drop off a little quicker than I would think the should at higher RPM.

I guess looking back, that 026 wasn't all that fast, but internet saw building was pretty much in it's infancy then. It's amazing how happy I was with just a muffler mod. lol
John

 

[wigglesworth]

I guess looking back, that 026 wasn't all that fast, but internet saw building was pretty much in it's infancy then. It's amazing how happy I was with just a muffler mod. lol
John

Its not amazing, its magic. That is how it all starts.