Grok answers which is better, the ST1100 or ST1300

[Andrew Shadow]

Sure.....but want it or not, they do change.

That's why Dyno results are corrected based on ambient temp, pressure and humidity, for comparable standard power readings.

I take no issue with what you write as you are absolutely correct. Those variables are always present and always uncontrollable for all vehicles at all times however. What I have observed was not only during one ride on one motorcycle done once, and not just by me. This was different riders with several different motorcycles on many rides in elevated altitudes over many years, over a couple of decades actually, so certainly varying atmospheric conditions as well. Through all of that it was noticeable to all of us that both of my ST1100's performed better at altitude than any other normally aspirated carbureted motorcycle that we had ridden. The only means by which were made aware of that was our butt dynos, but it was noticeable to all of us. So the salient point that I am making is that, beyond the atmosphere itself, there are design elements that can be incorporated in to a vehicle that allow it to minimize the effects of altitude better than vehicles that lack those elements. I don't know what they are.

 

[Larry Fine]

It would seem that there are design elements of engines, inductions systems, and carburetors, that can be used that allow the effects of higher altitude to be better managed and mitigated without adjusting the carburetor for altitude.

How do small planes do it?

 

[MidLife]

How do small planes do it?

Service ceiling of a Cessna 172 is 14 000 ft......

 

[Larry Fine]

Service ceiling of a Cessna 172 is 14 000 ft......

Is there any performance difference between near sea level compared to that altitude?

If someone attempts to fly higher, does the power taper off? Is there compensation?

 

[MidLife]

Is there any performance difference between near sea level compared to that altitude?

If someone attempts to fly higher, does the power taper off? Is there compensation?

Power is tapering off with every foot of elevation, no way around it, that's physics.

Over the ceiling, the remaining power is no longer sufficient to sustain a safe climbing rate.

To compensate for the rarefied atmosphere, different engines are required.

An engine with a turbo can buy you another 5 to 10 000 ft.

A turbo prop plane, like the Pilatus, another 15 000 ft.

Then jet engines.....the U-2 spy plane was just below its 70 000 ft ceiling when hit by an SA-2.

 

[St-Gerard]

Most small planes have mixture control. A well designed carburetor does actually compensate for altitude a bit, less air pressure means less pressure to push fuel in to said throttle bore. Having said that computer control can be more accurate and adaptive.

 

[MidLife]

Most small planes have mixture control. .

You most likely know more about that than I do.

I've seen this control, as a passenger, in a Cessna 150.

It was then only used during level flight cruising, to lean the engine to the max and save fuel while less than full power was needed. Pull the knob back until the engine starts puttering and then push back a bit. Never used to optimize mixture under full power.

During takeoff and climbing, at any altitude, it was always pushed in to full rich. Even for landing, it was kept at full rich, in case full power might be needed for a go around, At least, that's how this one pilot was handling it.

And that was over half a century ago, things may have changed.