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Old 09-11-2010, 10:35 PM   #1
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Default this is annoying now

this is the 3rd servo i've burnt out.

as throttle/brake in my xray 808

i set my epas correctly, but yet i burn them after 1-3 runs.

what the hell is going on?

already cost me $300.00 on servos...
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Old 09-11-2010, 11:03 PM   #2
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Originally Posted by 808gx7r View Post
this is the 3rd servo i've burnt out.

as throttle/brake in my xray 808

i set my epas correctly, but yet i burn them after 1-3 runs.

what the hell is going on?

already cost me $300.00 on servos...
Are you mounting them with grommetts?
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Old 09-11-2010, 11:04 PM   #3
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My guess is chassis flex on jumps and it bangs into the servo housing. There's ways to help with this such as shimming it a bit so it sits higher.
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Old 09-11-2010, 11:08 PM   #4
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make sure the linkage for the throttle is straight!...meaning PERFECTLY horizontal!...OH and start running Hitec servos!,Because if you smoke them you can just take them straight back to where you got them and they should replace them!...FOR FREE!....Hitec is the only servo company that allows hobby shops to just swap out servos for free! as long as it wasnt caught on fire or smashed or whatnot!
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Old 09-11-2010, 11:23 PM   #5
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yes i use servo grommets, but it cant be chassis flex as i havnt been to a track in ages... i burnt one out in the park today and i barly touched full throttle or full brake

it cant be perfect because my carb sits different.(gx7r) but i am using a aftermarket alloy arm.
will try some stock plastic ones. as they have more mounting positions.
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Old 09-11-2010, 11:31 PM   #6
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Quote:
Originally Posted by Dredd View Post
My guess is chassis flex on jumps and it bangs into the servo housing. There's ways to help with this such as shimming it a bit so it sits higher.
also On the EPA. The chassis flexes a lot, and if you set the high speed epa to go all the way until the carb opens completely it could theoretically harm the servo. Limit the throttle throw to have about 2mm play in it with the trigger pulled all the way. Check this by pulling the trigger all the way, and then grabbing the throttle rod and pulling it. It should pull out farther than the epa is set....

Also. If you adjust the brake pads a bit closer you can reduce the brake throw a bit so the servo doesn't have to work so hard to stop the car....

I hope this helps......
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Old 09-11-2010, 11:36 PM   #7
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Quote:
Originally Posted by merdith6 View Post
also On the EPA. The chassis flexes a lot, and if you set the high speed epa to go all the way until the carb opens completely it could theoretically harm the servo. Limit the throttle throw to have about 2mm play in it with the trigger pulled all the way. Check this by pulling the trigger all the way, and then grabbing the throttle rod and pulling it. It should pull out farther than the epa is set....

Also. If you adjust the brake pads a bit closer you can reduce the brake throw a bit so the servo doesn't have to work so hard to stop the car....

I hope this helps......




+1 thats the way i set my throttle epa and that is true about the servo doesnt have work as hard if you adjust the brake pads closer they seem to work better that way too ! but i have my throttle linkage where theres about 1mm pull.


also what really helps is a extended one piece engine mount it gets rid of that flex.
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Old 09-11-2010, 11:43 PM   #8
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+1 thats the way i set my throttle epa and that is true about the servo doesnt have work as hard if you adjust the brake pads closer they seem to work better that way too ! but i have my throttle linkage where theres about 1mm pull.


also what really helps is a extended one piece engine mount it gets rid of that flex.
mine goes 2-3mm xtra after "full throttle" as with these long needle engines tunes change when you have it go further then the opening
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Old 09-11-2010, 11:47 PM   #9
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Check the return spring length on the throttle linkage. Depending on where you set your brakes found on mine it gets coil bound & loads the servo if not adjusted, so just chop a bit of. EPA is the other area to look at but your on top of thaqt..
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Old 09-11-2010, 11:47 PM   #10
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What servos are you running? Did you mount it CLEAR off the chassis? You said you used the rubber grommets but did you loosen it up a bit for some gives?
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Old 09-11-2010, 11:54 PM   #11
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People often don't think throttle servos need much torque. They absolutely do. Use a good, high torque, digital servo.
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Old 09-11-2010, 11:57 PM   #12
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Originally Posted by 808gx7r View Post
mine goes 2-3mm xtra after "full throttle" as with these long needle engines tunes change when you have it go further then the opening

um i never heard of when you change the needles you have to go futher on the epa thats a new one to me . well also what i was meaning was when i go full throttle its not all the way open theres a little bit of the carb showing but still has about 1mm to 2mm pull left.
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Old 09-12-2010, 12:00 AM   #13
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Quote:
Originally Posted by 808gx7r View Post
mine goes 2-3mm xtra after "full throttle" as with these long needle engines tunes change when you have it go further then the opening

um i never heard of when you change the needles you have to go futher on the epa thats a new one to me . well also what i was meaning was when i go full throttle its not all the way open theres a little bit of the carb showing but still has about 1mm to 2mm pull left.


i usually just tune my needles and leave the throttle epa where its at.
but i do have a losi .


sorry double post dam computer keeps on acting up again.
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Old 09-12-2010, 12:00 AM   #14
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um i never heard of when you change the needles you have to go futher on the epa thats a new one to me . well also what i was meaning was when i go full throttle its not all the way open theres a little bit of the carb showing but still has about 1mm to 2mm pull left.
the type of carb... the more the carb barrel is pulled the more fuel it lets in.
its a go engines gx7r.. which is why people get so stuffed up with the tuning of these
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Old 09-12-2010, 12:01 AM   #15
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Hitec 7955. Problem solved. I would also check all of your wires to make sure there are no cuts or frays. Had a friend keep blowing servos because of the wiring.
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