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Old 01-27-2017, 08:40 PM
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Default How to improve rear motor steering

I've spent countless hours trying to get my Rustler to turn.
This is mainly to improve ON-POWER steering but by moving my lead weight to the very front of the car both my on-power and off-power steering have VASTLY improved. This setup also improves upon the poor braking performance that the Rustler is known for.

The basic premise:
Lower rear camber link (stock)
Reduce rear negative camber
Reduce rear toe (zero is stock)
Add small amount of front toe out (1 degree is plenty)
Softer front springs/shock oil
Stiffer rear springs/shock oil
Lengthen front camber links
Lay down front shocks more than rear
Add a little weight to front
Softer front tires than rear tires

Now on to my setup:
TheRoadWarrior
19/83 gearing
Castle Creations 4600kv
Castle Creations SV3 with fan
Associated XP ds1015 steering servo (201,.108)
Front: Black Losi 4.1lb/in 2" front spring
Rear: Stock Rustler 2.9lb/in 2.5" rear spring
B2/B4 shock mounts
50wt/35wt oil
Stock Traxxas Ultra shocks
Front shock shaft titanium-nitride coated
Front/Rear Preload: 8mm front/14mm rear
Front/Rear Shocks lowered: 2sml/1lrg2sml
Front/Rear droop: 11mm/1mm
RPM wide mod
STRC Front shock tower
STRC Rear shock tower
Front: Long Camber Link setting
Rear: High roll center setting
Toe: 1 degree toe-out/-1.5 degrees
Camber: -2/-.5degrees
RPM bumper upside-down
Traxxas aluminum bulkhead
Traxxas aluminum 30 degree caster block
Traxxas aluminum front hub carrier
Traxxas aluminum bellcrank
Nitro 4-Tec 1.5 degree rear stub carrier
Bandit body
1.5oz lead weight in bulkhead
1.25oz lead weight on bumper
Tires: Proline Dirt Hawgs/Proline Dirt Hawgs
Temperature and Voltage Telemetry
Traxxas wheelie bar with rubber wheels
Slipper setting: 1/2 turn out
Steering sensitivity @25.2%
Throttle expo @zero%
Steering dual rate @100%
Sub-trim: 0%
Right Steering end point @84.8%
Left Steering end point @100%
Throttle EPA: 100%
Brake EPA: 75.2%
Brakes @80%
TSM setting: 50%
ESC setting: 1.Forward/brake/Reverse, 2.Brakes 50%, 3.Reverse speed 25%, 4.Punch control level 1.High, 5.Drag brake zero, 6.Dead Band Normal(.1ms), 7.Voltage cutoff Auto, 8.Motor timing Lowest(0 degrees), 9.Motor type Brushless
Traxxas 3s 5000mah 25C
Front/Rear track width: 13.6"/13.3"
Ride Height: 27mm/27mm

Yes that's the longer 3s 5000mah battery that fits the Slash and E-Revo. It weighs 2.2oz more than my 3s 4000mah 25C so I made up for the weight in the front. The longer battery improves braking performance and gives longer run time.

Last edited by DeathVirus; 02-08-2017 at 11:08 AM.
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Old 01-27-2017, 10:59 PM
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Reduce front front droop for onpower steering.
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Old 01-28-2017, 01:16 AM
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Yes. Put limiters in the front shocks for on power steering. Try 0.5mm at a time but don't go too far. Any more than 2mm and it's time to try other things. Also tryou adjusting your driving. I've seen so many times through my 20+ years of rc that driving techniques are the root of a lot of problems. When I'm struggling with set up I have someone else I respect drive my vehicle and listen to what they say. Surprisingly that helps a lot
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Old 01-28-2017, 09:04 AM
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All the things that you have tried have helped but the drawback to the Traxxas design is in the trans. The planetary gear in the trans does not really help with on power steering. While trying to turn on power one side of it unloads and one of the wheels loses power. Few way to fix this. Proline trans with 5000 or higher diff fluid, Bad Horsie Locking diff grease or FLM sealed diff.
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Old 01-30-2017, 04:08 PM
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Originally Posted by JsK
Reduce front front droop for onpower steering.
why reduce? when the weight shifts to the rear you'll still want the front tires on the ground.
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Old 01-30-2017, 04:14 PM
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Originally Posted by DeathVirus
why reduce? when the weight shifts to the rear you'll still want the front tires on the ground.
limiting it keeps the weight from shifting to the rear
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Old 01-30-2017, 04:29 PM
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Im interested too because i was just told the lack of droop on my B6D was the reason for lack of on power steering. When I increased droop by moving my lower shock mount in, my steering improved.
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Old 01-30-2017, 05:02 PM
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Originally Posted by caioz1jp
Im interested too because i was just told the lack of droop on my B6D was the reason for lack of on power steering. When I increased droop by moving my lower shock mount in, my steering improved.
I've heard both sides of the coin about this. Some say limit front droop bc it allows more weight to shift to the rear and others say you need the front droop to keep the front tires on the ground.

If you're shifting the weight to the rear [as you move forward] and you limit front droop, wont the front wheels just come off the ground anyway?
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Old 01-30-2017, 05:23 PM
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To me the best way to have more steering while accelerating is to add anti squat at the back and if not enough shorter rear camber link if you can do it on the car.
Although this shifts more weight to the rear (higher kept CG) the fact that the car squats less means the rear RC doesn't drop much while on power => better steering while accelerating (roll axis leans less to the back).
Shorter rear camber link is to be dealt, if you're happy with the rest, only in case of desperation and you've maxed the anti squat as it will influence on other things.
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Old 01-30-2017, 05:47 PM
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Originally Posted by caioz1jp
Im interested too because i was just told the lack of droop on my B6D was the reason for lack of on power steering. When I increased droop by moving my lower shock mount in, my steering improved.
Moving shocks in on the arms effectively softens your spring rate too, so that's not isolating the effects of more or less droop.
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Old 01-30-2017, 07:49 PM
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Originally Posted by Callaway
Moving shocks in on the arms effectively softens your spring rate too, so that's not isolating the effects of more or less droop.
That would depend on how many holes he moved by. If it's only 1 hole in that's not as much of a difference in terms of spring rate/dampening rate as it is in the amount of droop he gains, wouldn't you think?
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Old 01-30-2017, 07:55 PM
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Take the shocks apart and add 3mm of spacers between the piston and shock body to limit
droop. Whatever you did to add front droop reverse it.

More antisquat is next.
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Old 01-30-2017, 08:14 PM
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Originally Posted by DeathVirus
That would depend on how many holes he moved by. If it's only 1 hole in that's not as much of a difference in terms of spring rate/dampening rate as it is in the amount of droop he gains, wouldn't you think?
That depends on geometry and physics that I do not have adequate inputs to calculate. But I wouldn't think so. A one hole change is quite noticeable to me, and I haven't been doing this but two years.
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Old 01-31-2017, 07:05 AM
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Originally Posted by JsK
Reduce front front droop for onpower steering.
What's a good amount of downtravel limiters to use on the front shocks? I see race setups for the b4.2 for Ryan Cavalieri and he uses 3 in the front but what size are those?
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Old 01-31-2017, 07:21 AM
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Originally Posted by DeathVirus
What's a good amount of downtravel limiters to use on the front shocks? I see race setups for the b4.2 for Ryan Cavalieri and he uses 3 in the front but what size are those?
1mm each, your prob not going to want to run more than 3 to 4 mm of limiters, after that you
should start adding antisquat in the back.
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