Throttle Return Spring - Slide Carb

[Nitroaddict]

This is a dumb question, but it came up this past weekend. I had a race, and got yelled at for not having a TRS. I had a failsafe on it, so they let me race, but it got me thinking. How do I put a TRS on a slide carb small block? It is for my NTC3. Anyone have any photos of their or someone else's setups?

 

[Error401]

My experience with the TRS is that it's useless unless it can overcome the resistance of your throttle servo (with no power applied). If the spring don't have the balls to pull it back to idle, it's just there for looks. The savage comes with one, but it is pretty gutless with the stock throttle servo. I put a Futaba 9401 HS coreless BB aileron servo in the throttle slot. This servo has almost no resistance with no power and the spring does it's job, along with the failsafe. But with the stock one, forget it.

 

[Nitroaddict]

i think u r missing my point, error - i need to know the mounting positions of the TRS.

because of the slide carb's design and the way the engine mounts in the NTC3, i can't figure out where the hell to put it.

 

[NCNitro]

I had seen someplace where a o-ring was used on a slide carb as a return, I will see if I can find the article for you.

 

[Nitroaddict]

thanks eddy - but my club says i need to use a "spring" or i can't race next time. grrrr - stupid rules.

 

[NCNitro]

Originally posted by Nitroaddict
thanks eddy - but my club says i need to use a "spring" or i can't race next time. grrrr - stupid rules.

Eddy?...Poor little kitty

 

[Maxxcrazy88]

can you mount it on the servo horn??????

not familiar with the ntc3 sooo......

but just connect one end to the horn and another to well what ever works..........

(if this can't be done disregaurd this post)

 

[LarryA]

Sounds like a jerk off rule if you have a failsafe. Are you sure they are not realated to the people who run NASCAR? They have managed to come up with some pretty keen rules too. By the sound of it they have "inspection" which may or may not be good. That depends on who is doing the inspecting, a competator or a non competing independant. Anyway, I guess rules are rules, so put a light spring on it so it looks good. You might be able to use a ball end that has a eye in it or just go around under the ball cup like the savage does.

 

[GilBeQuick]

The article about the o-ring is in the premeir issue of RC Driver. I looked for a suitable o-ring for my slide carb, but I couldn't find one that would would let me still put my filter on good enough so that it wouldn't fall off easily.
As for location, I can't find anyway to do it. As said earlier, it is absolutely useless unless your spring can overpower your servo. Stupid rule if you're running a failsafe.

 

[Error401]

Originally posted by GilBeQuick
As said earlier, it is absolutely useless unless your spring can overpower your servo. Stupid rule if you're running a failsafe.

Thanks man, that was my point. And if they're real anal about the "rules", do what LarryA said and make a poser TRS just for looks.

 

[Çh®i§tiªñ]

I still think if you completely loose power for some weird reason, an o-ring or small rubber band (like for braces wrapped twice) it will be certain to close that barrel. A servo without power can be overcome pretty easily if they are maintained.

I say roll with both and you get the best of all of it.

 

[Candyman]

Seems pretty anal to require that it be a "spring". I saw the o-ring mod in RC Driver and it looks simple and effective. Will they allow you to hook it to the servo arm, or does it have to be attached to the slide? If so, I have no clue where to hook it up..

 

[NCNitro]

Originally posted by Candyman
I saw the o-ring mod in RC Driver and it looks simple and effective.

THANK YOU! I have been going crazy trying to remember where I had seen that.

 

[Nitroaddict]

sorry about the killed kitten, NC. as for all that asked, here are the answers to the questions, maybe this will help u help me, as i stillhave no idea where to put it.

yes, they do a visual, and mechanical inspection

they check to make sure the TRS actually works. No visual only.

yes, the spring can be attached to the servo horn

no, an o ring cannot be used.


help.......

 

[RobH]

NA, i run a TRS on my big block slide card. I doubt this tip would change much for a small block.

I attached one side of my spring to a ziptie on the carb neck and the other end to my throttle linkage. i used a farily large spring that wouldn't do you much good. i'm sure it would work well if you coulf find the right size TRS.

To test it, I turn the power off on the reciever and manuallly force the throttle open (overcomming the TRS). Then I just let go of the servo horn and see if the spring has enough power to bring the servo horn back. it's all in the length of the spring.

i've seen that rubber band thing a few times now and i don't like the whole corrosive-replacement factor. to each his own though. *shrug*

-Rob

 

[Nitroaddict]

thanks rob - i can picture what u are talking about, and will look at what i have when i get home.

go check your PM's

 

[robriguez]

I was toying with the O-ring suggestion from RcDriver but I would rather have something that I'm not going to worry about wearing out or breaking.

Couldnt you use the same idea as far as position on the carb/throttle linkage but use a spring instead of an o-ring??

 

[slothy]

Originally posted by GilBeQuick
As said earlier, it is absolutely useless unless your spring can overpower your servo. Stupid rule if you're running a failsafe.

ya but failsafe does jack shiat if your battery pack or servo gets disconnected.. , failsafe only works if the RX lost signal with TX..

 

[Çh®i§tiªñ]

Originally posted by Çh®i§tiªñ
I still think if you completely loose power for some weird reason, an o-ring or small rubber band (like for braces wrapped twice) it will be certain to close that barrel. A servo without power can be overcome pretty easily if they are maintained.

I say roll with both and you get the best of all of it.

 

[Nitroaddict]

UPDATE

based on something similar to Rob's idea - i solved the TRS problem. i went and got a heavy duty door hinge spring from Lowes. Attached it from the servo horn to a screw that attaches the right radio tray. works great!