RE: Throttle curve
Linear rpm change is not what you want.
You want linear power output. As with all engines or electric motors...The planes response tot eh power is what you are looking for. The boys that have flown electric understand this too....Linear does not feel linear in the models pull department.
Part of this is the way the motors work and getting into their power curve...they just don't pull down low rpms, and part of it is the efficiency issue with the props and how they are interacting with the airframe.
Like I said before.....You will have to tune it to your tastes... Personally for me linear doesn't work. You can try all you want but I think linear response will leave you with not much happening before half power.
We all try to say we want linear throttle response....this does not mean that we want linear rpm change with throttle....Fly the model and tune it to your liking....
If you are doing 3D stuff you will want a fairly flat curve where your hovering power will be. This way you can make fine tuning adjustments up and down.....but not have one click barely hold the model and the next click have it climbing out....
If you are flying sequence stuff you will want a cruise throttle stick position you are comfortable with. Some guys like to be 1/2 stick...they might use a notch at this cruise point. I have tried this and I don't think it really helps you fly better. I feel it is a handicap in some cases.
What I do think is important is that you get a power output change and that would require a rpm change too....with every click of throttle. SO you don't want to get to 3/4 stick and the power or rpm of the model doesn't change.
So this is a play with and see what you like. Don't shoot for linear as it may not be the best for you and your needs. Everytime I fly someones model and they set it up like you suggest it feels absolutely dead below half power.
The 2 stroke pattern engines on a pipe will be worse at this dead below half power...as no matter what the setup used it will have some pipe affects....This makes it tough...Also throttling up through the range will give one rpm at a certain point and throttling down and coming off the pipe the rpms at the same point will be different...This is one reason I don't run 2 strokes. However you can play games with a throttle curve to help this situation...and make it feel like there is not the step...
For me this is one reason I like the 4 stroke engines. Each engine will have its own curve too. I am flying and have been flying the 170DZ for a couple years now. Drop a 160 in the same spot and I tweak the throttle curve a little to get it to feel the same as the 170 did.
Another trick is on the 4 stroke is using a velocity stack or restrictor in the carb. Yes it restricts top end power by a couple hundred rpm but ti makes the bottom of the power curve come alive and smooths out the power delivery. So a 170DZ with or with a velocity stack installed will have different response.
There are lots of things that go into it.....You want the model to respond linearly not have the rpms change linearly....So is it really linear....Nope it is just what feels right to you.
Reality is 1/2 stick for me is about 60% power. This is what feels best for me...It may not for you.
Troy Newman