my DA 50 has a very noticeable throttle delay. it is not there when i start the engine but, few minutes in the air and the delay starts. i've played around with my low needle to see if it helps but it didn't. also, there's no slop in the linkage, so i don't know what's causing this? the only thing i haven't done is to change the throttle servo. i've go a hitec 925MG on the throttle.
another thing is that i've put about 50% expo on the throttle so at half stick i get about half the rpm's but, that shouldn't cause the delay.

thanks

dude, get rid of that expo and see if the delay goes. I think the expo is causing this delay. I suggest you run this engine in the "raw" without much radio tweaks until you know its running perfectly. I have about 4 gallons thru mine and never needed any expo on the throttle curve as I thnk its "quite" linear anyway.

the funny thing is that visually my linkage is linear but in reality i was getting around 6K at center stick. i'll remove the expo and see if it helps.

I think that you'll find that your DA-50 is getting most of its power in the first 1/2 to 2/3 of the throttle server (butterfly valve) movement, and there is little to no RPM increase beyond that point. I use a 13 point curve in my 9z with a noticeable flat spot that brings center stick down to about 25-30% of the servo travel. Then the curve moves up steeply past the 70% point. This curve has proven to be very linear on the RPM increases on my DA-50 using a KS-1060 tuned pipe and a Mezjlik 23X8 prop.

What Tx are you using? Do you have throttle curve capability?

I use a 9 CAP and it has a 5 point curve, though not the same as a 13 point curve I'm going to try and see if i can get a more linear response using the 5 point curve.
also, coming back to the delay, if the problem was the expo, i would feel the delay even when i start the engine. why do i only get the delay once I'm in the air?

How far away are you flying the plane? It could just be the delay d/t the speed of sound???

the best way to go about this to measure the amout of throw from idle to wot at the card and set your servo arm up for the same throws and it will work every time.then just use end points to fine tune it

Use the inside hole on the throttle servo arm and the outside hole on the carb lever to obtain the max linkage travel distance. Then adjust the end points to get the stops right. Play the throttle curve from there if you still have a need for it.

I run 50 to 70% expo on the throttle so I can hover at mid-stick. Without expo or a curve you'll find the first half of the throttle stick gives you 90% of the throttle, the last half does almost nothing.

Not sure what you mean by delay? If the low end is too lean you will get a bog followed by a delayed throttle response.

It has been my experience that when the low end is too lean there is no transition, the engine dies when the throttle is opened..
If the low end is too rich the engine will bog and the ignition will not advance, making it worse...