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Adjusting Savage X 4.6 Brakes

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Old 12-02-2012, 06:25 PM
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Default Adjusting Savage X 4.6 Brakes



I've noticed that the braking on my Savage X 4.6 have decreased with each run....to the point now I'd say there are "no brakes" on the it. I found this out the hard way duringa speed run tonight (luckily the street was empty and I let the vehicle coast to a stop).

I understand how to adjust brakes/linkage on buggies, but the MT seems a little different. On initial glance, there seems to be two ways to adjust the brakes:
1. Adjust the plasting screw next to the spring (I know I should use fuel tubing, but there is a spring on for now).
2. The vertical arm on looks like it can be modified by dropping the arm down some and then re-tightening the screw.


Above all, I want to ensure I don't employ drag. However, at this point I have NO brakes on the Savage, and am curious if there is a simply way to adjust before I tear into it.

Thanks!

See attached pic.

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Old 12-02-2012, 07:00 PM
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Default RE: Adjusting Savage X 4.6 Brakes

Lowering the arm will decrease leverage and decrease stopping power, but the will come on faster. Search the ofna linkage mod and do it, it will solve so many issues for you. If not, replace the spring with fuel tubing and adjust the brakes with the adjuster wheel on the end of the rod. Also the factory servo is quite weak.
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Old 12-03-2012, 08:05 AM
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Default RE: Adjusting Savage X 4.6 Brakes

Quote:
ORIGINAL: steed2
Lowering the arm will decrease leverage and decrease stopping power, but the will come on faster.
Thanks for the replyI want to ensure I understand you here. By lowing the arm (right side of the picture) it will DECREASE stopping powe....but the brakes will be applied faster?

Quote:
ORIGINAL: steed2
Search the ofna linkage mod and do it, it will solve so many issues for you.
Thanks, I just checked this out and it looks very interesting indeed. Seems I'm not the only Savage owner with braking issues.

Quote:
ORIGINAL: steed2
If not, replace the spring with fuel tubing and adjust the brakes with the adjuster wheel on the end of the rod. Also the factory servo is quite weak.
I think (in order) Iwill try the following:
1. Replace spring with fuel tube. How long? 2"???
2. Try the 'OFNA linkage' mod
3. Upgrade servo with more torque.

Thanks!
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Old 12-03-2012, 11:29 AM
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Default RE: Adjusting Savage X 4.6 Brakes

If you do those three the truck will flip right over with ease...also you are running a rechargeable hump pack right? And by the way my savage brakes were horrible. I usually upgrade the steering servo and use the sf2 for throttle/brake
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Old 12-03-2012, 11:34 AM
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Default RE: Adjusting Savage X 4.6 Brakes

Yes lowering it will have that effect, you lose leverage but gain movement when compared to the center of rotation.
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Old 12-03-2012, 12:46 PM
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Default RE: Adjusting Savage X 4.6 Brakes

Double check to make sure the bolts that hold the breaks to the transmision have not come loose. When they come loose your adjustments will change and breaks fade.
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Old 12-03-2012, 06:53 PM
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Default RE: Adjusting Savage X 4.6 Brakes


Quote:
ORIGINAL: Ttowntoolman

Double check to make sure the bolts that hold the breaks to the transmision have not come loose. When they come loose your adjustments will change and breaks fade.
Thanks, guys. One note: the three things I mentioned above I will do, is ONLYIF the first does not work. ;-) Thus I will first put the fuel tubing on...if that does not work, try the OFNA linkage....etc.

Quick question regarding switching the spring with tubing:

What is easiest method to remove the spring? Doesadjustment screw come off......or should I remove the brakelinkage from the servohorn?

I am curious how the truck has slowly lost it's ability to brake. As noted, it has pretty much NObraking ability at all. So much I can't run it. I am adept withworking onbuggies (I change/clean my break pads often), and have learned you don't "compensate" else you affect other parts....so it is important to understand theroot cause. My biggest fear is putting pressure on the engine due to drag.

With that, Ttowntoolman (or anyone)....would you be kind enough to give me the part number of the bolts you are referencing? Do I need to remove the transmission, or can I access the bolts from under the truck?

Thanks!
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Old 12-03-2012, 09:31 PM
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Default RE: Adjusting Savage X 4.6 Brakes

They are not bolts, are screws
That's the problem here. The screws are getting loose on the pads. Lock tite will not fix the problem. Use a dab of tire glue to prevent this from happening over and over again.
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Old 12-04-2012, 10:19 AM
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Default RE: Adjusting Savage X 4.6 Brakes

Yea man just turn it over and look at the brake pad assembly on the outside of the transmission on the bottom. The two SCREWS that go through the assembly and hold it to the transmission are most likely loose. Should be Phillips heads...........
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Old 12-04-2012, 10:23 AM
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Default RE: Adjusting Savage X 4.6 Brakes

[quote]ORIGINAL: Ttowntoolman
OOPS fat fingers.....
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Old 12-04-2012, 11:37 AM
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Default RE: Adjusting Savage X 4.6 Brakes

I believe you are referring to the step screw (part Z280).

See attached for clarificartion. However, these are adjustable and needed to take off for changing pads, so obviously don't want to locktite nor tire glue them.

If this is not it, I'll wait until I get hom to take a look at it.

Thanks
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Old 12-05-2012, 04:56 AM
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Default RE: Adjusting Savage X 4.6 Brakes

Yep those are the ones. I check them when I feel a change in the braking.....
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Old 12-05-2012, 08:51 AM
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Default RE: Adjusting Savage X 4.6 Brakes

Awesome. Thanks so much! I'll let you know the results. We are moving over the next few weeks (so don't have a lot of time to work on it), but do plan to do one final run of it for my neighbors prior to our last night here. ;-)
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Old 12-05-2012, 05:42 PM
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Default RE: Adjusting Savage X 4.6 Brakes

I checked the screws on the calipers (by hand) and they were not loose. Instead of adjusting them (as I'm sure they are quite sensitive) I simply replaced the linkage spring with tubing and adjusted the thumb screw a little bit. I do like the fact I can guage the caliper play without removing the transmission, which makes it much easier to fine-tune.

Thanks for everyone's help.
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Old 12-09-2012, 02:19 PM
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Default RE: Adjusting Savage X 4.6 Brakes

On top of making the adjustmets noted above, I have also found that deglazing the rotors with a Dremel sanding drum works well.
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Old 01-02-2013, 07:30 PM
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Default RE: Adjusting Savage X 4.6 Brakes

I've been trying to get my brakes working better too. (I noticed the same thing that they have gotten worse recently). I've got a hitec 645mg for the break/throttle servo as well as a hump pack for the power. I just saw on the hpi web site that they have a Stainless steel break set for the savage. Has anyone tried this? Did it help?
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Old 01-02-2013, 07:45 PM
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Default RE: Adjusting Savage X 4.6 Brakes

I didn't like them because the break pads tore and fell apart. I went back to using the stock again.
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Old 01-02-2013, 09:34 PM
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Default RE: Adjusting Savage X 4.6 Brakes

Quote:
ORIGINAL: AIRSAVAGE

I've been trying to get my brakes working better too. (I noticed the same thing that they have gotten worse recently). I've got a hitec 645mg for the break/throttle servo as well as a hump pack for the power. I just saw on the hpi web site that they have a Stainless steel break set for the savage. Has anyone tried this? Did it help?
I've used every stock setup there is from the Savage 25 single fiber disk to the twin SS and finally the twin fiber discs. The single disk would always overheat and fade, after 5 gallons or so the disk partially melted and stripped on the hub. The SS brakes work well but as mentioned the fiber pads for the calipers tear apart, I went through about 3 sets of these over a course of about 5-6 gallons. The dual fiber disks have by far given the best performance and reliability, after about 5 gallons I'm just now starting to notice the outer disk crumbling. I can do endos on demand and when I let people drive my truck they always slam on the brakes and flip the truck.

A tip to make the fiber disks last longer is to apply CA glue around the circumference of the disks. To get the best performance and adjustability, you want the OFNA throttle mod. Its that much better than stock, I've been running mine for about 5 years and about 12 gallons and never any issues.
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Old 01-03-2013, 04:26 AM
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Default RE: Adjusting Savage X 4.6 Brakes

I origninally installed a stronger steering servo and used the stock steering servo for the throttle/brakes which helped a bit. I also upgraded to the dual disc system which helped some more.

I also installed fuel tubing which helped even more, but not a lot. However, my braking always seemed to slowly fade during a bash session, and it seemed to be due to the batteries draining. I use 4 AA NiMH in the stock battery box.

This occurs because when you operate the brakes, considerable servo force (accompanied with rapid battery drain) is needed to overcome the override spring in the stock servo arm system.

I then bent the brake arm for better leverage, and it helped some more, but still not perfect:



Eventually, I did my own version of the OFNA throttle Mod using various bits I had in my junk box. I did have to lengthen the steering horn, but a longer one could easily have been bought cheap.

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