Subscribed. Great Thread! Very timely for my new DLE 120.

Terry,


I've used your method with great results for a while now. Any tips on how one would go about applying some of this to a 4 cylinder? I'm considering a DLE 222 v3 for an Extreme Flight 125" I'm going to start this fall and I've always been curious about the ease, or difficulty of tuning 2 carbs.


-Scott

Originally Posted by sthudson

Terry,

I've used your method with great results for a while now. Any tips on how one would go about applying some of this to a 4 cylinder? I'm considering a DLE 222 v3 for an Extreme Flight 125" I'm going to start this fall and I've always been curious about the ease, or difficulty of tuning 2 carbs.

-Scott

I've not owned one, but I've helped tune a few. Pretty much tune them the same, but typically the rear just a tiny bit more rich than the front when you are done. Depends a lot on your baffling, air exit, etc. as well. I'd advise downloading the manual for the DA200 and start with that as a guide. Over all the low and high will tune the same as described in this thread.

Hope you are OK with this Terry, but I took your great method and summarized it for myself to carry in my field box, and now I actually have it on my phone. Here's the pdf summary I did:

Originally Posted by Judge

Hope you are OK with this Terry, but I took your great method and summarized it for myself to carry in my field box, and now I actually have it on my phone. Here's the pdf summary I did:

Very nice

....

Originally Posted by orthobird

From Day 1, tune your quad, and tune it to your prop and your location/weather/altitude, etc....

Good lesson for ALL engines. That's why I list that there is no factory needles, even from DA. Yes, they run them.....BUT. I can buy a brand new DA and it does not transition at my elevation. Elevation, prop, humidity all effect it.

Working on tuning on of my DA35s. Today while trying to work on high end needle, I noticed that at full throttle the motor would bog down just a hair. When I pulled back on the throttle just a hair, it would hit top end easily.

Anybody ever have this happen? What does it mean?

...

Thanks, I suspected it was lean.

OK... on the low end... When I chop throttle after WOT run up the motor will immediately hit a steady idle that is just a bit faster RPM than when I start out. (I start out somewhere around 1700-1800 RPM. Then when I chop throttle it immediately goes to maybe 1900-2000 RPM and holds it for maybe 15 to 20 seconds and then loads up and drops back to 1800. If I slam the throttle it pops right back up to max RPM no problem.

BUT if I let it sit and idle for a minute or more, it will puff some smoke when I slam the throttle. AND if I let it sit for several minutes it will eventually cut off if I don't give it a nudge.

Originally Posted by deadrobmusic

Thanks, I suspected it was lean.

OK... on the low end... When I chop throttle after WOT run up the motor will immediately hit a steady idle that is just a bit faster RPM than when I start out. (I start out somewhere around 1700-1800 RPM. Then when I chop throttle it immediately goes to maybe 1900-2000 RPM and holds it for maybe 15 to 20 seconds and then loads up and drops back to 1800. If I slam the throttle it pops right back up to max RPM no problem.

BUT if I let it sit and idle for a minute or more, it will puff some smoke when I slam the throttle. AND if I let it sit for several minutes it will eventually cut off if I don't give it a nudge.

Sounds like you are lean on the H and rich on the L. Go back through the tuning step by step. Don't skip a step and don't go out of order and you will end up with a nicely tuned engine. If you are still rich on the L then you did not finish tuning the L before you started with the H. That or your H was lean from the start.

If I were tuning that, right now I would open the H to factory setting or at least 1/8 more than you are now. Then tune the L starting with the first step in the tuning guide.

Originally Posted by deadrobmusic

Thanks, I suspected it was lean.

OK... on the low end... When I chop throttle after WOT run up the motor will immediately hit a steady idle that is just a bit faster RPM than when I start out. (I start out somewhere around 1700-1800 RPM. Then when I chop throttle it immediately goes to maybe 1900-2000 RPM and holds it for maybe 15 to 20 seconds and then loads up and drops back to 1800. If I slam the throttle it pops right back up to max RPM no problem.

BUT if I let it sit and idle for a minute or more, it will puff some smoke when I slam the throttle. AND if I let it sit for several minutes it will eventually cut off if I don't give it a nudge.

That's all exactly correct. If it's taking a sec to drop back down to your original idle then it's a touch lean on the top end.

The second part is just the nature of a carb. Even older cars with carbs have the same issues. If they just sit there on idle they will eventually load up. You have to clear them out every now and then. It should have no issue going up to 20 seconds without needing a bump though. You should be able to slam it to full and have a slight hesitation.

Originally Posted by Colton

That's all exactly correct. If it's taking a sec to drop back down to your original idle then it's a touch lean on the top end.

The second part is just the nature of a carb. Even older cars with carbs have the same issues. If they just sit there on idle they will eventually load up. You have to clear them out every now and then. It should have no issue going up to 20 seconds without needing a bump though. You should be able to slam it to full and have a slight hesitation.

Thanks Colton. And do you agree that if it runs higher RPM when I pull of the throttle just a hair, then it is lean on HIGH end?

Originally Posted by deadrobmusic

Thanks Colton. And do you agree that if it runs higher RPM when I pull of the throttle just a hair, then it is lean on HIGH end?

Yep. That's what I was saying in the first line

Originally Posted by Colton

Yep. That's what I was saying in the first line

Thanks... Slowly getting the hang of it