THROTTLE CURVE
#1
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I'M NEW TO GAS ENGINES I NEED/WANT TO USE ALL OF MY THROTTLE STICK, NOT JUST THE FIRST QUARTER ! MY TX HAS NO T/CURVE IS IT WORTH THE INVESTMENT, I HAVE ALREADY DOWNSIZED PROP + ADJUSTED SERVO MECHANICALLY , IS THERE A CARB THAT WILL GIVE WIDER RANGE (3W70i)
#2
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From: camborne, UNITED KINGDOM
do you mean the carb is opening to halfway but theres not much difference afterwards, ie- getting full power at half throttle if you know what i mean.
thats normal with most engines, half throttle on the carby is more like 80% of the total power of the engine, the only way you can change this (to my knowledge(i've never had to do it)) to a more linear throttle curve is to adjust it on the servo to carb linkage and mess around with different geometry.
good luck and STOP SHOUTING!
thats normal with most engines, half throttle on the carby is more like 80% of the total power of the engine, the only way you can change this (to my knowledge(i've never had to do it)) to a more linear throttle curve is to adjust it on the servo to carb linkage and mess around with different geometry.
good luck and STOP SHOUTING!
#3
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From: Lincoln,
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Ditto on what cabanestrut2002 said. Most carbs are very non-linear in thier operation. At 1/2 stick, I typically have the carb open 25%-33%. If you radio has a free mix, maybe you can mix throttle to throttle somehow to mimic a throttle curve. Otherwise, you are limited to mechanically mixing out as best you can. Cheers.
#4

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Someone suggested to use your tachometer and throttle curve set points to get it right. I assume the Heli boys do this, but I'm using a 9Z and have been meaning to set my curve points. I haven't done it yet but it sounds the right way to get the job done. I just put a ton of expo on that channel and haven't fooled with it since yet.
RickP
RickP
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From: Spanish Fort, AL
Use a very short servo arm and lengthen the throttle arm. You may hve to add a piece to the arm. Use a 2-56 bolt and some JB weld if you need to. Make sure the servo is full forward at off, pointing at the throttle, and it will help the geometry also.
Bean
Bean
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From: CamborneCornwall, UNITED KINGDOM
most of my planes i leave as is, but on the Cougar and Capiche i've set expo to give a better curve for Hanging/smooth pattern flight, simply start the engine, goto expo ch3 and play with it and the throttle stick until you get the kinda of responce you want from the engine.
you can aslo play with where the servo arm is, the less the angle from snake to arm, the more the arm moves for the same snake movement. you get most movement at 90 degrees of course. if you set the arm so at idle most movement is from almost 180 ( or 0 ) degrees towards 90. using ball links allows you to get the links over the arm as it travels over the servo. in most cases the idle would have the servo arm facing at the rear abut 160-170 degrees from the snake, throttle cut is just that extra little bit up to 180. you should hit full throttle by the time you get to 90 degrees, or at most 70.
hope that makes sense, if not i'll draw up a picy
you can aslo play with where the servo arm is, the less the angle from snake to arm, the more the arm moves for the same snake movement. you get most movement at 90 degrees of course. if you set the arm so at idle most movement is from almost 180 ( or 0 ) degrees towards 90. using ball links allows you to get the links over the arm as it travels over the servo. in most cases the idle would have the servo arm facing at the rear abut 160-170 degrees from the snake, throttle cut is just that extra little bit up to 180. you should hit full throttle by the time you get to 90 degrees, or at most 70.
hope that makes sense, if not i'll draw up a picy
#9
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Thanks guys, i gueess i need to play about with the connections/ travel e.t.c. the only proplem is the carb and throttle are directly behind the engine in the 'box bay' i can't see a damn thing, it took me 5 mins to attach the clevis to the servo arm. I could do with one of those mirrors dentists use. Sreiously i would buy one if anyone knows where i can get one. Me spellins getin as baa as Edibkle Endgones. Hey have you lot seen the thread MAAC new 3D rulles ? Its a reel HOOT.
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From: CamborneCornwall, UNITED KINGDOM
your stutters pretty bad too eddy
much easier to play with expo in your case, btw, those mirros are easy to get hold of, most rc shops that sell little clamps, helping hands cheap nicknack, etc etc, normally have some, if not i'm sure your local pain giver ( dentist ) will be able to point you in the right direction.
might want to drill a hole in the top of the box to unscrew the horn, and nother to help line up the clevis
much easier to play with expo in your case, btw, those mirros are easy to get hold of, most rc shops that sell little clamps, helping hands cheap nicknack, etc etc, normally have some, if not i'm sure your local pain giver ( dentist ) will be able to point you in the right direction.
might want to drill a hole in the top of the box to unscrew the horn, and nother to help line up the clevis
#14
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Unfortunetly my tx doesn't have expo on throttle (jr378), but it does have offsett on any mix, by mixing throttle into throttle with offset just b4 mid throttle stick (where the mix comes into effect) has gave me full throttle stick range. Brill idea John Willman cheers.
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From: Essex, UNITED KINGDOM
It shoudl work, some people in aerobatic comps were the engines noise level has to be under 82DB people do a throttle to throtle mix so the carb doesnt epen fully so the engine isnt at full powere therfore it isnt as l;owd



