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Old 10-23-2015, 06:14 AM
  #436  
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Check the set screw on the uprights. The 3.5 shims are in the rear upper arm only to give a little of reactive caster to the suspension.
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Old 10-23-2015, 06:40 AM
  #437  
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Originally Posted by CFRacing
Check the set screw on the uprights. The 3.5 shims are in the rear upper arm only to give a little of reactive caster to the suspension.
Ok, I think I follow you now. You mean that not all the pin should be covered by spacers right? I need have 2,5 above the uprigth, set the uprigth accordingly and then add 3mm below to control droop, rigth?

Regarding the 3,5mm in the rear upper arm. Where do you add them? Under the ballstud above the motor bulkhead I have 1mm. Do you add 3,5 mm below the ballstud on top of the battery plate?

Thanks for all the help!
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Old 10-23-2015, 07:19 AM
  #438  
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Originally Posted by fmm
Ok, I think I follow you now. You mean that not all the pin should be covered by spacers right? I need have 2,5 above the uprigth, set the uprigth accordingly and then add 3mm below to control droop, rigth?

Regarding the 3,5mm in the rear upper arm. Where do you add them? Under the ballstud above the motor bulkhead I have 1mm. Do you add 3,5 mm below the ballstud on top of the battery plate?

Thanks for all the help!
you got it right,2.5 will give you the ride height. regarding the 3.5 shims they go
under the rear pivot ball of the upper arm of the front suspension. if you give me an email address i'l send you some pics. pm me
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Old 04-28-2016, 07:39 AM
  #439  
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My SJF01 is quite loose in the rear - I get a lot of spins or oversteer off throttle when going into a corner. What adjustments would anyone recommend?

I seem to be able to handle power out of corners ok, it's just the lift or braking into corners that seems to cause most of the issue.

I thought having my battery to the most rear would help, but it doesn't seem to change much.
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Old 04-28-2016, 08:16 AM
  #440  
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Do you have any drag brake set on your ESC?
Are you running on asphalt or carpet?
What tires are you using?
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Old 04-28-2016, 08:20 AM
  #441  
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Anybody else noticing that Speedpassion SP-1 front end parts are drying up? I had been buying those for spares, but can't find them anywhere now. So I am buying Streetjam parts from RC-Art.
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Old 04-28-2016, 10:44 AM
  #442  
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Originally Posted by funked1
Do you have any drag brake set on your ESC?
Are you running on asphalt or carpet?
What tires are you using?
ESC doesn't support it, but I've tried adding and removing it through my transmitter. Seems best when I set it that there's enough drag brake that I don't really need to brake at all.

Carpet track.

Run a couple different kinds, all pretty similar. The best was Pit soft rears and medium fronts.
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Old 04-28-2016, 11:07 PM
  #443  
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I use the drag brake the same way. But if I have it set too strong, the car will spin out entering turns like you are describing.
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Old 04-29-2016, 09:41 AM
  #444  
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Originally Posted by funked1
I use the drag brake the same way. But if I have it set too strong, the car will spin out entering turns like you are describing.
Adding some drag brake helped a little bit but there's other things that I need to change. It was a lot worse with no drag brake.
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Old 04-29-2016, 09:50 AM
  #445  
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Right, it will just plain spin out with push brake a lot of times. Try no drag brake and just getting off the gas earlier instead of braking.
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Old 04-29-2016, 10:50 AM
  #446  
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#1 take droop out of the rear of the car

#2 take camber out

#3 stiffer front spring

Also, widen front end, raise front ride height. If you want to use push brake, keep adjusting the brake side end point lower until the car brakes straight. Too much brake will snatch the tires.
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Old 04-30-2016, 12:56 PM
  #447  
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Gidday Robk,

I'm not sure how removing rear droop would help a loose car. Rear droop only adds grip to the rear end in my understanding. It does not affect weight transfer in any way. It does however let the wheel go down further for better road holding characteristics.
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Old 05-02-2016, 09:54 AM
  #448  
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less rear pod droop lessens the amount of weight transfer to the front tires off power, increasing rear grip off power, corner entry

same as rear droop on a sedan
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Old 05-02-2016, 12:44 PM
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Originally Posted by ixlr8nz
Gidday Robk,

I'm not sure how removing rear droop would help a loose car. Rear droop only adds grip to the rear end in my understanding. It does not affect weight transfer in any way. It does however let the wheel go down further for better road holding characteristics.
As Jay said, the more droop in the rear the more weight dumps on the nose. Yes, you do need some droop if the track is bumpy. On link cars the effect is more pronounced than a t bar car.

If you want on power stability, add front droop. Same idea.

Just do a few laps, unscrew the shock end, do a couple more laps, and then wind it in as far as you can. You'll quickly see the differences.
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Old 05-02-2016, 11:13 PM
  #450  
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Gidday Rob and Co,

Consider this, when you use very little droop on the rear, all that actually happens is the rear inside wheel leaves the ground under braking into a corner(extreme case). This reduces grip at the rear. This has no affect on weight transfer as the car will keep transfering weight regardless of whether the wheel is on the ground or not.

The simple answer is if you want to reduce weight transfer, then change the springs/ shock oil/ roll centre at the end that requires it. These things affect weight transfer.

Heres another interesting post from a few years ago on rctech:

Actually, look at a biker doing a "stoppie" (reverse wheelie onto front wheel under front-wheel braking). There is no force from the rear tyre that is stopping it from leaving the ground, no fulcrum at the point of contact of the tyre and the road to provide a lever.

Same happens in a car, just so happens that we don't have the high/forward CG of a bike, and there isn't enough weight transfer to lift the wheels off the ground completely. What happens is they lift from the ground instantaneously, and in a 4wd car this decreases braking force, decreasing deceleration, decreasing weight transfer to the front, increasing weight retained at the rear, and putting the tyres instantaneously back on the ground, from where they will instantaneously become unloaded again if the brakes are still on!

So less droop decreases grip. Although as seaball said quite early on you need to be at very small amounts of droop (he mentioned 1.5mm, I'm inclined to agree), before you start to really see the handling effects. Anything above that and the car rarely hits the droop limiters.
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