R/C Tech Forums

R/C Tech Forums (https://www.rctech.net/forum/)
-   Radio and Electronics (https://www.rctech.net/forum/radio-electronics-137/)
-   -   3pks servo activity (https://www.rctech.net/forum/radio-electronics/539622-3pks-servo-activity.html)

valk 08-07-2011 10:41 AM

3pks servo activity
 
just curious if im tripping or if somone else has had a similar issue. I have a 2PL-2.4G i have been using since i started racing. just upgraded to a 3PKS FASST with a ton more features.

for whatever reason though it seems like the throttle servo activity was smoother with the 2PL than with the 3PK on my nitro car. the throttle servo wont return fully to neutral unless you blip the brakes and the carb slide seems to open kinda jerky. i unhooked the linkage and the carb slides smooth.. just not sure why the different radio gives a different result.

i reset the model settings to default. using a 603FF rx in the car and JR Z270 throttle servo.

the only other thing i can think of is the previous owner cut the antenna short. but ive rear that this isnt a big deal for 2.4GHZ systems.

edit; throttle doesnt seem to open completely if i slowly squeeze the trigger. i have to squeeze it quickly to fully open.

J.Whiting 08-07-2011 10:54 AM

i dont know if this is your issue but i had a 3pk that when i pulled the throttle 1/16-1/8 finger pull the throttle would go 3/4 open on the motor.. then when i got to 1/2 throttle the carb would go the rest of the way.. what i found on mine was a bad throttle potentiometer.. replace the trigger assembly and all worked well.. sold this radio locally to a guy and has used it for several years now with no issues...

also if you remove the carb linkage does the throttle act the same?? some times a cab sticking will cause this issue.. also a weak servo will cause this if your carb is sticking... jeremy

valk 08-07-2011 11:03 AM

its possible the pot is bad i suppose though my tc5 drives just fine with the radio. excellent throttle response. i imagine the servos in this car are pretty low end. though it seems to have enough balls to lock the brakes pretty good. ill have to muck around with the travel. have my throttle epa set to like 25 and 90 for the brake, maybe thats not enough travel for the throttle even though the car is full open.

J.Whiting 08-07-2011 11:14 AM


Originally Posted by valk (Post 9493161)
its possible the pot is bad i suppose though my tc5 drives just fine with the radio. excellent throttle response. i imagine the servos in this car are pretty low end. though it seems to have enough balls to lock the brakes pretty good. ill have to muck around with the travel. have my throttle epa set to like 25 and 90 for the brake, maybe thats not enough travel for the throttle even though the car is full open.

those are about the same setting i had on my throttle settings when the throttle trigger was bad... they should be closer together.. like 50ish on throttle and 60ish on brakes.. just an example... try this... leave throttle alone but use the buttons to move the breaks or throttle epa up and down... by 40-80%.. does the servo horn move when you do this?? if it does you have a bad throttle trigger.. that is what mine did.. i was adding more brakes and i noticed the servo was moving with epa settings.. this should not happen at all... jeremy

valk 08-07-2011 11:22 AM

to clearify; you mean dont touch the throttle trigger but use the +/- to move the epa?

doing that the servo doesn't move. it only moves if i engage the trigger and adjust it.

though i have to set the brake epa to almost 80 to get it to move any on trigger action.

J.Whiting 08-07-2011 11:26 AM


Originally Posted by valk (Post 9493209)
to clearify; you mean dont touch the throttle trigger but use the +/- to move the epa?

doing that the servo doesn't move. it only moves if i engage the trigger and adjust it.

though i have to set the brake epa to almost 80 to get it to move any on trigger action.

correct... did you take the carb linkege off and try moving the throttle? does it move free and smooth?

valk 08-07-2011 11:32 AM

yes i tried that. carb moves smooth though i havent run the engine today so it might have gummed up a little by sitting.

i plugged my 2pl system back in and it doesnt seem any better. so maybe its just a fubared servo. ill take the steering servo out of my touring car and see how it works.
I have a spare hitec servo i plugged in but it was really jittery and noisy for some reason. didnt try it with the 2pl though.

valk 08-07-2011 11:51 AM

alright. nevermind. switched my new savox 1258tg in from my touring car and its super smooth and responsive. guess ill just replace the servos in the car. didnt expect them to be amazing for the cost of the car but this jr just doesnt work well at all.

J.Whiting 08-07-2011 12:02 PM


Originally Posted by valk (Post 9493286)
alright. nevermind. switched my new savox 1258tg in from my touring car and its super smooth and responsive. guess ill just replace the servos in the car. didnt expect them to be amazing for the cost of the car but this jr just doesnt work well at all.

glad you figured it out.. electrical gremlins are the worst.. jeremy

valk 08-07-2011 12:13 PM

now all i have to figure out is how to not break half the fricken car when i tap...


All times are GMT -7. It is currently 11:51 AM.

Powered By: vBulletin v3.9.3.9 Patch Level 3
Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.