Need throttle curve help on gasser
#1
Member
Thread Starter
Join Date: Mar 2008
Location: Richmond Hill,
ON, CANADA
Posts: 85
Likes: 0
Received 0 Likes
on
0 Posts

I have DLE 55, my first gasser. Noted the throttle (butterfly) is much different responce to glow (barrel) type carbs. Specfically, with my gasser, at 1/2 throttle, I get 6300 RPM, and WOT I get 6700RPM....not much diff from 1/2 to WOT. The linkage is smooth and linear, I think the issue is that a butterfly carb doesn't work same as glow type. So my question...do you set in a throttle curve to compnsate...? If yes...do you still make the carb go WOT or do you set the curve that its MAX RPM...even if MAX RPM is not WOT ?
Suggestions ?
Suggestions ?
#2
Senior Member
My Feedback: (12)
Join Date: Aug 2002
Location: Gaston,
SC
Posts: 576
Likes: 0
Received 0 Likes
on
0 Posts

Sounds like the end points are off and the linkage set up too...I have a steering arm on my throttle..The pushrod is in the second hole closest to the carb and on the servo end, its on the very end one. The radio is 100 on the idle and 100 on the wot...
#4

My Feedback: (9)
Join Date: Jul 2003
Location: Pullman,
WA
Posts: 2,221
Likes: 0
Received 0 Likes
on
0 Posts

I use a curve on my DLE engines. I have the first five points or so set so that the first 3/4 of stick only moves the throttle about 30% then the last two points take it open to 100%.
Sam
Sam
#6

My Feedback: (2)
Join Date: Jan 2003
Location: Billingsley, AL
Posts: 736
Likes: 0
Received 0 Likes
on
0 Posts

The first thing to do is lengthen the carb arm to match the servo arm so they move the same. The little short carb arms will really complicate setting up linkages. Then use the curve for the final setup. I tap the holes in the carb arm to 4-40 or just bolt a piece of fiberglas, etc. thru the hole in the arm. You can also offset the arm that way for better geometry.
#9
Senior Member
My Feedback: (2)
Join Date: Oct 2002
Location: Potomac, MD
Posts: 642
Likes: 0
Received 0 Likes
on
0 Posts

I don't have throttle curve programming available on my old 8 channel.... so used a mechanical curve... at idle - the thottle servo arm is almost pointed at the motor.... full thottle is about 90 degrees. Seems to work very well... but if anything... I could still use even less initial advance... someday I am going to have to upgrade my transmitter!
#10
Senior Member
Join Date: Aug 2006
Location: Euless,
TX
Posts: 217
Likes: 0
Received 0 Likes
on
0 Posts

Does anyone know what size and thread the walbro throttle lever screw is?? I want to use the blue metal servo arm on top of the throttle arm of my walbro carb and secure the two together. However, the throttle lever screw is not long enough to pass through the servo arm AND the walbro throttle arm. I need a longer screw. The screw is part # 96-142 but I don't know what size it is. I looked on the website and left a voicemail. Does anyone know what size and thread the walbro throttle lever screw is??
#11

My Feedback: (41)
Join Date: Aug 2003
Location: Milwaukee,
WI
Posts: 10,259
Likes: 0
Received 0 Likes
on
0 Posts

It's not exactly 4-40 but 4-40 will thread in there safely. Use a tiny bit of blue lock tite. You don't want it coming out. I have done this on two engines and it works awesome. Use as long of a bolt as you can to get the most threads in there....but don't bottom it out and snap the bolt of course.