R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Nitro Off-Road

Reply
 
Thread Tools Search this Thread
Old 04-08-2008, 05:22 PM   #1
Tech Fanatic
 
d16dcoe45's Avatar
 
Join Date: Oct 2007
Location: Armonk, NY
Posts: 944
Trader Rating: 1 (100%+)
Default throttle servo for GT2?

I don't know if this has been covered before, but I recently ordered an Associated Gt2 which I plan to race at my local track this spring/summer. This is my first nitro vehicle--so I am not too versed in it.

My question is about throttle/brake servos. In my electrics I have been running mostly JR 9000s and Jr 9100s. They are both very fast (0.06sec) while the 9100s has more torque (180oz vs. 128oz). I plan to run a 9100s for the GT2 steering as it works well in my t4.

I assumed that I would want to run the same servo for the throttle, but my LHS owner told me that would be a bad idea. He was suggesting a $30 plasic geared analog servo!! Saying that if the throttle servo is too fast, it will make the car "jumpy" and hard to drive especially in gas truck.

I don't want a crappy servo. I know I want a digital metal gear servo, but is too fast "bad"? What about torque--is there such a thing as too much torque for a throttle servo? I just don't want to buy something twice. I understand his thinking with the speed, but is that true for everyone who runs gas truck?
__________________
Jay Lestingi

Tamiya 419x/Associated TC7.1/Sanwa M12s/Xpert servos
d16dcoe45 is offline   Reply With Quote
Old 04-08-2008, 06:01 PM   #2
Tech Addict
 
shady3031's Avatar
 
Join Date: Sep 2006
Location: Birmingham, AL
Posts: 594
Trader Rating: 26 (100%+)
Default

Currently i run airtronics 357's (128 at .08) for both steering and throttle with a 1500 mah lipo and a protek regulator all controlled with a nomadio radio. Gas truck is all about throttle control-so just pick a good servo and go have fun racing, just be sure all your endpoints are set correctly so not to burn up the servo and all should be fine. Some of the local drivers have tried to drive my truck and it usually takes them a few laps to get used to the speed of the throttle and steering, but i like a truck that is super responsive and does what i tell it to when i tell it to.

Jason
__________________
The Warehouse RC-Birmingham, AL
AE RC8.2-E Tekin powered
Alabama Manufacturers Shootout-Don't Miss It
shady3031 is offline   Reply With Quote
Old 04-08-2008, 06:49 PM   #3
Tech Fanatic
 
d16dcoe45's Avatar
 
Join Date: Oct 2007
Location: Armonk, NY
Posts: 944
Trader Rating: 1 (100%+)
Default

Yeah, my LHS owner was telling me I shouldn't really go quicker than 0.15-0.16, with 90-100oz of torque. He said plastic geared, analogue was fine. I don't agree with that--I think I will go with another 9000s, I could always slow it down on the radio if I don't like it.

On a similar note, he recommended an OS TZ with the understanding that its alot of motor. I am going to go with the TZ and I understand a rotary carb is smoother and better for off-road but he was of the opinion that you can also run a slide carb no problem in gas truck. Is a slide carb a total no-no for gas truck, or is driver preference?
__________________
Jay Lestingi

Tamiya 419x/Associated TC7.1/Sanwa M12s/Xpert servos
d16dcoe45 is offline   Reply With Quote
Old 04-08-2008, 08:49 PM   #4
Tech Champion
 
air8's Avatar
 
Join Date: Apr 2007
Location: Hutch, KS
Posts: 5,748
Trader Rating: 7 (100%+)
Default

As long as you're able to control your vehicle, the servo won't matter too much. I'd say use the JR-whichever you want. Just like you said you can tune it with your radio. I actually was frustrated with slower servos. When I wanted to let off the throttle at the last second the slower servos created some "run on," meaning the servo kept the carb open for a hair longer than I wanted. Also it wouldn't open quick enough for my taste.

Now on the engine. That TZ really rips. I'd like to try one also. Again you can detune the power a bit with the radio settings. Then you can work up to using full carb travel, and using the full speed of the servo. Personally I control the my GT2 around the corners using the throttle, so I perfer fast speed and slide carbs. I love how reactive the truck is, how responsive it is. It's great. I'd say put the Duece together how you perfer and you'll learn what works best.
__________________
--Driver...you are cleared into the track.....Smoke On.

--"U Ain't Fast!!"
Chris Pearce
air8 is offline   Reply With Quote
Old 04-08-2008, 09:07 PM   #5
Tech Addict
 
mxnut273's Avatar
 
Join Date: Jan 2007
Location: socal
Posts: 693
Trader Rating: 11 (100%+)
Default

i run a airtronics 737 plastic gear in my ad2 i think its like $30-40 never had a problem with it had it for over a year make sure your end pints are good u should be ok
mxnut273 is offline   Reply With Quote
Old 04-09-2008, 07:10 AM   #6
Tech Master
 
jnslprd's Avatar
 
Join Date: Feb 2005
Posts: 1,188
Trader Rating: 5 (100%+)
Default

Run a good servo for both throttle and steering, I try to buy servos i can switch in all of my car if need be. It is nice to be able to take a servo out of your gas truck and use it in your electrics if you are in a pinch or just dont want to buy servos for all of your cars We dont run gas truck in the winter so i use my throttle servo from my gt2 in my electric cars. i put the same airtronics 357 in all of my cars.----the os tz with slide carb is too much engine for a 2 wheel drive gas truck. You will find out real fast how hard it is to drive a gas truck with too much motor. If you look at all the pros trucks and setups you will see they all run rotary carbs and most have carb restrictors as well. The os tg with the rotary carb will be plenty of motor for this truck.
jnslprd is offline   Reply With Quote
Old 04-09-2008, 07:37 AM   #7
Tech Addict
 
mxnut273's Avatar
 
Join Date: Jan 2007
Location: socal
Posts: 693
Trader Rating: 11 (100%+)
Default

i think the 357 does have a plastic gear inside but i believe they make up-grade kit that swaps out the plastic for metal
mxnut273 is offline   Reply With Quote
Old 04-09-2008, 10:24 AM   #8
Tech Fanatic
 
d16dcoe45's Avatar
 
Join Date: Oct 2007
Location: Armonk, NY
Posts: 944
Trader Rating: 1 (100%+)
Default

Thanks guys. I don't think JR makes the 9000s anymore, it was replaced by the 9100s so I will get that. I thought of that, if I need to switch it to steering for one of my electrics I can do it no problem with a good servo.

I think you might be right about the motor. I didn't purchase it yet, so perhaps I will go with something more mild and a rotary carb.


Man, I am so excited about this GT2--I avoided nitro like the plague for so long, but after running with them on my local track, and the fact that they have a class in the summer for gas truck (tight indoor track) I figure I can run them with my electrics--plus that nitro smell got in my veins!!! good stuff...
__________________
Jay Lestingi

Tamiya 419x/Associated TC7.1/Sanwa M12s/Xpert servos
d16dcoe45 is offline   Reply With Quote
Old 04-09-2008, 09:12 PM   #9
Tech Champion
 
air8's Avatar
 
Join Date: Apr 2007
Location: Hutch, KS
Posts: 5,748
Trader Rating: 7 (100%+)
Default

Another option here, I have been using the Dynamite platinum .12 for 6 months now and it is a great engine. Very little tuning required and it has all the power needed to start with. Also the non platinum version is good from what I've heard. Also the Thunder Tiger Evo engines are wicked powerful for around $90 USD
__________________
--Driver...you are cleared into the track.....Smoke On.

--"U Ain't Fast!!"
Chris Pearce
air8 is offline   Reply With Quote
Old 04-09-2008, 09:20 PM   #10
Tech Initiate
 
MudLife's Avatar
 
Join Date: Jan 2008
Location: Lake Havasu City, AZ
Posts: 21
Default

hitech servos for both steering and throttle. spectrum reciever and remote is the way to go.
MudLife is offline   Reply With Quote
Old 04-09-2008, 09:43 PM   #11
Tech Fanatic
 
d16dcoe45's Avatar
 
Join Date: Oct 2007
Location: Armonk, NY
Posts: 944
Trader Rating: 1 (100%+)
Default

I have really been liking JR 9000s and 9100s servos--they are both rated at the same speed but the 9000s seems a bit faster. Futaba 9452 is pretty good too and might make a good throttle servo (.11/128 oz @ 6.0v)

I run Spektrum pro in a 3pk. The DX3r is neat but I wouldn't get one. If I ever had to replace my radio I would get the 4pk when it comes out or most likely an m11. But I have really been digging my 3pks so its staying for a good while. I always hear mixed things about Hitec servos. Some people seem to love them, some think they are junk, never ran them so I have no idea.

I want to go with a high quality engine, and OSs seem to be pretty proven and reliable--although I am sure most modern engines are pretty well put together.

Also, any particular brand of receiver pack I should go with? My LHS has a "generic" 1500 pack. I would like to get something with IB or EP cells--unless it won't matter. Is there a big advantage to running a lipo receiver pack? I am totally smitten by Lipo as I run Orion and SMC packs in my B4 and T4 but will it make a real difference as a receiver pack? How much do regulators run?

Besides the powerplant difference--does the gt2 handle any thing like a T4? In other words, my t4 is pretty dialed--is it possible a similar setup would work (at my track) on the gt2?
__________________
Jay Lestingi

Tamiya 419x/Associated TC7.1/Sanwa M12s/Xpert servos
d16dcoe45 is offline   Reply With Quote
Old 04-10-2008, 05:15 PM   #12
Tech Champion
 
air8's Avatar
 
Join Date: Apr 2007
Location: Hutch, KS
Posts: 5,748
Trader Rating: 7 (100%+)
Default

LOL. I don't think there is a comparison between the GT2 and the T4. I've been trying to get my GT2 to handle like my T4 for a while. I don't think it's going to happen. The chassis' are nothing alike. So I wouldn't expect something like that.

Lipos. I love them. Everything I have now is lipo. They stay consistent the whole time you use them. But if you run one in the GT2 the handling will be slightly off from what AE had in mind. Basically a few grams need to be added to the battery box to get to a base setting. I've done a couple of back to back comparisons and there is a bit of a difference in traction and handling. But this can all be adjusted with suspension tuning. The lipo pack will make the truck more sensitive to steering inputs. And in high speed corners the rear seems too light some times. The lighter lipo will not put as much weight on the outside tire to get the traction desired. If you use lipo you'll just have to play with the suspension till you find a comfortable spot.
__________________
--Driver...you are cleared into the track.....Smoke On.

--"U Ain't Fast!!"
Chris Pearce
air8 is offline   Reply With Quote
Old 04-10-2008, 05:31 PM   #13
Tech Addict
 
superdave2's Avatar
 
Join Date: Feb 2008
Location: mars
Posts: 699
Trader Rating: 3 (100%+)
Default

in my gt2 i ran 2 jr z590s (throttle and steering) i know there cheap and just stock servos but they did the job and more they were plenty for what i had
__________________
Team Terribles~ARCS Hobbies~Have Fun Hobbies~Answer-RC~Torco Fuel~Fastlane Graphix~ Caster Racing Products~Maxamps~Clockwork Racing Engines~BCG Industries
losi 8t dps .28 jr z9100s jr z9000t
spektrum dx3
superdave2 is offline   Reply With Quote
Old 04-10-2008, 07:10 PM   #14
Tech Fanatic
 
d16dcoe45's Avatar
 
Join Date: Oct 2007
Location: Armonk, NY
Posts: 944
Trader Rating: 1 (100%+)
Default

I know I keep harping on it but, when I switched from a Futaba servo that was similar in speed to a 590 (.16/90oz) to a 9000 and 9100s it totally changed the vehicle. It improved my lap times and made the car far easier to handle.

I will never run a standard servo again. Its that important. For bashing I suppose it doesn't matter but for racing there is no comparison.
__________________
Jay Lestingi

Tamiya 419x/Associated TC7.1/Sanwa M12s/Xpert servos
d16dcoe45 is offline   Reply With Quote
Old 04-11-2008, 03:30 AM   #15
Tech Addict
 
superdave2's Avatar
 
Join Date: Feb 2008
Location: mars
Posts: 699
Trader Rating: 3 (100%+)
Default

wel then your best bet would be go with what you want in it with the 9100 and the 9000
__________________
Team Terribles~ARCS Hobbies~Have Fun Hobbies~Answer-RC~Torco Fuel~Fastlane Graphix~ Caster Racing Products~Maxamps~Clockwork Racing Engines~BCG Industries
losi 8t dps .28 jr z9100s jr z9000t
spektrum dx3
superdave2 is offline   Reply With Quote
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
Steering servo and Throttle servo same speed? straightaway Nitro On-Road 4 11-06-2007 07:21 PM
Throttle servo gojoecrewchief1 Rookie Zone 5 09-14-2007 07:33 PM
Looking for throttle servo edward Haywood Nitro On-Road 34 08-01-2007 10:22 PM
Airtronics 94537 Servo Throttle Servo HS Imdadundada7 R/C Items: For Sale/Trade 23 06-19-2006 08:55 PM



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off



All times are GMT -7. It is currently 08:16 PM.


Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net