ofna throttle/ brake mod

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Foward throttle is great but when I go to apply brakes all that happens is I am putting so much strain /stress on the steering crank. My servo wants to pull the crank off the frame of the truck.
Thanks.

yea, pics & if you can also identify what you mean by 'steering crank' with a part # from your manual it would help.

we can prob help you with a easy fix, don't get frustrated.
 
yea, pics & if you can also identify what you mean by 'steering crank' with a part # from your manual it would help.

we can prob help you with a easy fix, don't get frustrated.

Yes I'll get some pics for you guys. I'm at work but when I get home I'll post them up. But the part numbers from the manual are plastic tree # 85058 # 2 and # 4. It's the part that looks like a Y. one linkage is connected to the carb ( ball cup) and the other linkage is connected to thethrottle servo arm. Hope that helps. Basicly it looks like this but something is clearly wrong.
 
I stole this pic from WHIPNET hope he doesnt mind. Should have asked him first.
 
That's called a throttle mixer. Yes, get us some pics.. we'll figure it out for you.

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No sweat man.. that's why they're posted.

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Thanks bro. Throttle mixer of course. When I get home I'll put the ofna mod together and take a pic. I have the stock setup back on now. It's got to be something stupid on my part. each time I give it brake the servo arm moves foward and it just seems like I didn't leave enough room with the linkage or something. I'll post up some pics and let you guys tell me what I did wrong, got to be something I missed.
 
OH by the way thanks guys for your replys and concern. I know I'll get it working. I just finished my build. I left the pull start on I'm not a fan but I'll give it a try first. OH ya I put the ofna foams on (tires) and didn't like the way they felt so I'm using the stock HPI foams for now. IT seemed to make the tire a little softer. Almost seemed like they were a tadf to small for the dirtbonds. Sorry going off on a tangent love my savage, Almost don't want to run it.
 
Is the spring setup in front of the server arm for the throttle? Is it catching or sliding forward as it is supposed to. It needs to be able to slide so it doesn't pull the throttle when braking.

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love my savage, Almost don't want to run it.

:slapped: your love for savage will deepen with every run my friend.


lol, yep, whip is right, your problem is on that upper link arm. you want the rod to be able to slide smoothly through your plastic ofna 'slider' and that spring to have enough tension when compressed to hold the carb closed, but not so tight that is stresses the throttle mixer.

You can even put a bend in your brake arm to if you want less travel in your linkage.

VVV in that pic, t/b servo horn is at nuetral, full brake in appx 3/8" forward slide so the spring compresses a bit less than 1/2 of how you see it now in nuetral
 
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Is the spring setup in front of the server arm for the throttle? Is it catching or sliding forward as it is supposed to. It needs to be able to slide so it doesn't pull the throttle when braking.

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Yes the spring setup is in front of the servo arm. but you are right I remember that it is not sliding foward it's getting bound up and pulling the throttle. But how would it slide without moving the servo arm? when I apply the brake the servo arm moves forward (towards the front of the truck) pulling everything foward.
 
Instead of the throttle moving it should slide up when the arm moves forward. I'll take some pics of mine in action shortly and post them.

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With the throttle on top, the first pic is neutral and the spring is not compressed and the arm is in the middle of the linkage slider.

<image removed>
The 2nd is 100% throttle. The arm pushes against the rear standoff.

<image removed>

The final is what I mentioned.. at 100% brake, the arm should not move your throttle forward much. It should slide and compress the spring. Giving it some tug against the throttle, but not enough to rip the mixer off. I got an aluminum mixer to take the slop out.

<image removed>
This is not the only way to do this mod. This is just how I did it.

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With the throttle on top, the first pic is neutral and the spring is not compressed and the arm is in the middle of the linkage slider.

throttle.arm-n.jpg


The 2nd is 100% throttle. The arm pushes against the rear standoff.

throttle.arm-t.jpg


The final is what I mentioned.. at 100% brake, the arm should not move your throttle forward much. It should slide and compress the spring. Giving it some tug against the throttle, but not enough to rip the mixer off. I got an aluminum mixer to take the slop out.

throttle.arm-b.jpg


This is not the only way to do this mod. This is just how I did it.

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Yes Thank you thank you thank you. I need to get home so I can get this thing working. I'll post back with my pics and results. And yes that is as simple as it gets, I don't think you could have done it better explaining that to me thanks again.
 
OK guys I got home late last night so I didn't have time to do anything about my setup. I think I understand what I did wrong. Well Like I said I will post pics of my setup before I start to fool with it. I want you guys to see just what I did so I can get some feedback. You guys are great.
 
OK I did it. Thanks guys, what a difference it took a while but it's done. By the way Whipnet, where is your screw that goes into the threaded spacer. I'm talking about the aluminium spacer that goes inside the purple plastic pieces that attach to the servo arm. I don't see it.
 
By the way Whipnet, where is your screw that goes into the threaded spacer. I'm talking about the aluminium spacer that goes inside the purple plastic pieces that attach to the servo arm. I don't see it.

Congrats on getting this done. If I am understanding correctly you are talking about where the slides connect to the servo horn?

Do you have pictures of what you are talking about? Or can you point them out in my pictures with an arrow?

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Congrats on getting this done. If I am understanding correctly you are talking about where the slides connect to the servo horn?

Do you have pictures of what you are talking about? Or can you point them out in my pictures with an arrow?

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I can post a pic but not at the moment. How do I show you with an arrow? I'm sorry for my lack of computer knowledge. If you look at your pic, inbetween the two collets you have your plastic slides. I have a screw that screws into the aluminium insert that slips into the plastic slide, I don't see one in your pic. I was just wondering how you attached everything.
 
I can post a pic but not at the moment. How do I show you with an arrow? I'm sorry for my lack of computer knowledge. If you look at your pic, inbetween the two collets you have your plastic slides. I have a screw that screws into the aluminium insert that slips into the plastic slide, I don't see one in your pic. I was just wondering how you attached everything.

OK, I think I know what you are talking about. What appears to be a hole connecting the top and bottom sliders to servo horn.

It's been a loooooooong time since I did this mod. I think I might have come up from the bottom, but I really don't remember. I will get home and take a look at it and take some pictures of how I connected it.

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OK, I think I know what you are talking about. What appears to be a hole connecting the top and bottom sliders to servo horn.

It's been a loooooooong time since I did this mod. I think I might have come up from the bottom, but I really don't remember. I will get home and take a look at it and take some pictures of how I connected it.

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OK thanks, don't worry about it I was just wondering how you got it to stay together without the screw. I have a lock nut on the bottom holding the screw in place.
 
OK thanks, don't worry about it I was just wondering how you got it to stay together without the screw. I have a lock nut on the bottom holding the screw in place.

No worries.

I have the screw coming from under:
tm.under.jpg


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OK here are some pics of the Ofna mod and some pics of my new build. I can't figure out how to copy the pic right to this forum. Sorry about using the link guys. I hope I did this right.
IMG_1855.jpg

IMG_1861.jpg

IMG_1862.jpg

IMG_1863.jpg

IMG_1866.jpg

IMG_1868.jpg

IMG_1869.jpg

IMG_1870.jpg

IMG_1854.jpg
 
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Fixed the images for you. Looks great man.

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Ya I noticed that thanks man. How did you do that? Well you don't have to explain. But how on earth do I post my images like you just did to mine? I saw that you replied to my post and sad to myself WOW I really did post them right. Then saw that you fixed them LoL. Thanks again dude that was real nice of you.
 
you had your images inside of the [url ] and [/url ]
You need to put
around the link to the image. Or hit that button that looks like a mountain and a yellow sky on the format toolbar above and insert link there.

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OK thanks. I used photobucket I'll have to look for that mountain and a yellow sky button. Well when I post some more pics I'll test it out. Thanks again.
 

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