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Why has my savage got a throttle return spring when my Buggy hasn't?

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Why has my savage got a throttle return spring when my Buggy hasn't?

Old 08-29-2005, 05:42 AM
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youie
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Default Why has my savage got a throttle return spring when my Buggy hasn't?

Savages are fitted with a throttle return spring, yet my Lightning buggy does not have one. I have constantly lagged behind my friends Hoboa pirate MT despite the fact that his Mt and My Savage are both fitted with the same RB 728 (.28) engine. The other day I removed the throttle return spring with the confidence that if the buggy can work without one then, so can the Savage. And OH BOY! it made a difference alright, a massive difference as the standard throttle servo only managed to open the throttle a smidge past half way. Now it opens up fully and my friends a trailing behind me. If there are any justifiable reasons why I should replace the spring then please let me know.
Old 08-29-2005, 07:05 AM
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Default RE: Why has my savage got a throttle return spring when my Buggy hasn't?

My throttle return spring gave me problems until I ordered the ofna throttle linkage mod. Basically the return spring wasnt strong enough to close the throttle all the way and so when I braked and released the trigger, the throttle would not have been closed properly and the truck would shoot off again.
Im not sure if this has any bearing in your case as youve removed it entirely, but if you have to start holding the brake on until youve got hold of your truck, then thats probably your problem.
Old 08-29-2005, 07:19 AM
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Default RE: Why has my savage got a throttle return spring when my Buggy hasn't?

ORIGINAL: youie
If there are any justifiable reasons why I should replace the spring then please let me know.
The only good reason is the original reason it's on there in the first place... safety. If your linkage comes apart, or your rx dies, would you rather have your engine return to idle, or go screaming off at whatever throttle setting you had it on? Throttle return springs are there to prevent runaways. You may never need it, but if you don't have it on, you may regret it.

If you couldn't open the throttle all the way with it on, there is either something wrong with the linkage, radio setup, or your servo is too weak( are you by any chance using 4 rechargables in your receiver pack?). There are many people with the same truck that can go full throttle with no problem.
Old 08-29-2005, 08:26 AM
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Default RE: Why has my savage got a throttle return spring when my Buggy hasn't?

^^^ agree with all the points that Gerwen made...

Safety....one of the original mods was to use a balloon to return the throttle. Good to see that HPI listened.

Sounds if you cant go to full throttle its either/or a weak servo (HPI recommends a minimum of 5kg servos) or badly adjusted linkages.
Took me a good hour + to get mine set just right and opening to full throttle.

Hope it helps.
Old 08-29-2005, 11:09 AM
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Default RE: Why has my savage got a throttle return spring when my Buggy hasn't?

The spring is the first thing I threw away. I never drove my truck with that spring on for a few reasons; First, It did't look like the carb could open all the way with the spring on. It sure did with the spring off! Second, it puts extra strain on the somewhat weak (stock) servo. It's trying to open full throttle but the spring wouldn't allow it. And third, and most important, you get faster throttle response without it.

Reasons for keeping it on; As mentioned above, safety. If your linkage comes apart then there is a possibility of a runaway with out the spring. But, the chances of that are unlikely. Unless you bash without the body on.

Personally, the reasons for not having it is far greater then having it. So I turfed mine.

I've had my Savage for two years with over 5 Gallons of fuel threw it. I never had a runaway. I've always made sure the batteries in the receiver and radio are always charged to minimize the chances. I use to use the truck a fair bit. Now, not nearly as much. New baby []. So I broke down and just bought a failsafe. That way, when I blow the dust off it and take it for a burn, I'm protected against low batteries.

But I'll never put that spring back on.
Old 08-29-2005, 02:28 PM
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Default RE: Why has my savage got a throttle return spring when my Buggy hasn't?

I never had problems with my throttle opening all the way with the stock servo. If I remember correctly my Savage came with an updated spring that was to replace the spring that was already installed on the carb. I am pretty sure it had less tension than the stock spring to compensate for the crappy stock servo.

BTW, a failsafe won't help if the linkage pops off and also the spring won't close the throttle when radio signal is lost.
Old 08-29-2005, 05:45 PM
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Default RE: Why has my savage got a throttle return spring when my Buggy hasn't?


ORIGINAL: imdjenk

BTW, a failsafe won't help if the linkage pops off and also the spring won't close the throttle when radio signal is lost.

I know a failsafe won't help if the linkage pops off. But you shouldn't be concerned about that and don't know why anyone would unless you bash your savage without the body on. Then, you are asking for it.

I just purchased a failsafe to protect against a lost signal (I typically run mine in a very large open field) as that is what a failsafe is designed to do.

If, as you say, the spring won't close the throttle when the signal is lost, then it is ONLY there in the unlikley event of the linkage popping off!! Ya know what? I think that spring can be put to better use. Like a spare for your favourite ball point pen! IMO.





Old 08-29-2005, 06:03 PM
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Default RE: Why has my savage got a throttle return spring when my Buggy hasn't?

Mine stays on cause I don't have problems with it, and since then I have upgraded servos anyway. But you're right, it is unlikely that the throttle link will pop off, though it can happen or the pivot arm can break. Better safe.
Old 08-29-2005, 06:23 PM
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Default RE: Why has my savage got a throttle return spring when my Buggy hasn't?

I found the stock spring way too stiff, far too much tension. I set mine up with a lighter govner spring off a Briggs motor, its the cats ass.
Old 08-29-2005, 08:39 PM
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Default RE: Why has my savage got a throttle return spring when my Buggy hasn't?

BTW, a failsafe won't help if the linkage pops off and also the spring won't close the throttle when radio signal is lost.
Sorry, but I have to disagree. Most cats @ the track run a heavy throt. return spring in event of a lost signal.
When batts. die or signal is lost, the spring returns the servo all the way back. Much more reliable than an
electronic fail safe(most of wich cause glitching). Most buggy owners I met just use a rubber band.
I use 2 stock springs hooked to my roll bar & have no problem hitting WOT.

Tudogs
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Old 08-29-2005, 09:37 PM
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imdjenk
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Default RE: Why has my savage got a throttle return spring when my Buggy hasn't?

The stock spring on mine is not strong enough to move throttle enough to bring the servo to the closed position. I wish I had that dual spring setup on my RC10GT because I lost signal and WOT into a tree the other day. The heads for the bolts holding in the front shock tower got sheared off.
Old 08-30-2005, 06:16 AM
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Default RE: Why has my savage got a throttle return spring when my Buggy hasn't?

The Ofna throttle mod must have been the easiest & cheapest mod that I have done yet.
Come time to do the Ofna tank mod, all I had to do was flip everything 180 deg & adjust the linkage.

The stock spring on mine is not strong enough to move throttle enough to bring the servo to the closed position.
Have you tried to relocate the spring to the roll bar? The stock mount for the return spring is a joke. I moved it long before I did the
ofna mod.

Tudogs
Old 08-30-2005, 10:04 AM
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Default RE: Why has my savage got a throttle return spring when my Buggy hasn't?

where can i get this mod?(throttle linkage)
Old 08-30-2005, 06:08 PM
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Default RE: Why has my savage got a throttle return spring when my Buggy hasn't?

Here is why you need a throttle return spring http://www.rcuniverse.com/forum/m_33...tm.htm#3314579
Old 08-30-2005, 07:50 PM
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Default RE: Why has my savage got a throttle return spring when my Buggy hasn't?

ORIGINAL: ntloser

I think I am going to throw in the towel. I brought my Savage with a new engine and werks clutch the LHS. I assembled the engine and clutch myself but the clutch wasn't engaging properly. After taking the engine off and adjuting it several time with no luck, I decided to bring it to the LHS thinking I was doing something wrong.

I called the LHS today to see if it was done. They told me the throttle linkage popped off and the engine was wide open and the truck hit the wall. I am using an OFNA linkage and he L piece from the Savage uses a ball and socket to connect to the throttle servo . The shop said the socket piece popped off the ball. of course I couldn't duplicate that and never experienced that problem before. Nobody could tell me why there wasn't a throttle return spring on the truck. Which would have prevented this from happening. Anyway the shop said they would go over it tomorrow and everything would be free. I looked at the truck and I don't even see any cosmetic damage. My questions are;

1. Has anybody using the ofna throttle linkage had the socket come off the ball?
2. Should I make the shop rebuild the truck from the ground up to make sure there isn't anything damaged that I can't see?
3. Can I sue the shop for emotional distress?

If you pop that ball off that socket too many times, then it is possible it can easily pop off on it's own. My guess is that when you or the LHS put the engine in, either you or your LHS:
1. Was worn so much form popping on an off so many times, it fell off.
2. Didn't pop in on completely.
or
3. forgot to put it on.
Old 08-30-2005, 07:58 PM
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Default RE: Why has my savage got a throttle return spring when my Buggy hasn't?

The the ball ad socket mechanism was probably put on and off 3 times maybe. I put it together while waiting for the new engine to come so it has hardly been used. However, if the throttle return spring was on, it wouldn't have been a problem. Should I super glue the ball to the socket?
Old 08-30-2005, 08:40 PM
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Default RE: Why has my savage got a throttle return spring when my Buggy hasn't?


ORIGINAL: ntloser

Should I super glue the ball to the socket?

Of course not. That ball has to rotate a little in that socket. You must consider that it was possible it wasn't put on fully and simply came off at the expense of your LHS. If you are confident that it's tight when popping it on, then it shouldn't be a problem. However, given the circumstances, I would put the throttle return spring back on. So, if it does pop off on it's own accord, then you have the protection. And if that happens, then replace the plastic socket with a new one.

Old 08-30-2005, 09:26 PM
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ntloser
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Default RE: Why has my savage got a throttle return spring when my Buggy hasn't?

Agreed. I don't understand why the LHS didn't have the throttle return spring on there anyway....When i brought the truck in, the engine and pipe were in an seperate box... Anyway.. I feel they should have put the spring on.. but this is starting to turn into the other thread I made..

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