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Rs4 sport 3 brushless darting off to side under hard acceleration?help please, im a newbie

Discussion in 'Race - Newbe Q' started by billclinton, Jul 20, 2016.

  1. billclinton

    billclinton New Member

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    Please help, i drag race my rs4 sport 3, it runs a tenshock 550 5000kv 120a esc, 81 spur, 37 pinion, locked front and rear, gyro tuned way down. The issue is wh3n i accelerates hard the tires hop bad, and it darts off the road, does any1 know what causes this? Is it the suspension? Too soft of too stiff? Ive tried a few things and cant figure it out. Thanks
     
    #1 billclinton, Jul 20, 2016
    Last edited: Jul 21, 2016
  2. Magnat007

    Magnat007 Proud SCX10 Owner
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    Sometimes its just a case of too much power for the chassis..
    All RC Cars have a power limit.. Like real cars..
    As soon as you try and dump too much power into the vehicle your power to weight ratio goes out of balance.
    Its really hard to get the Ideal balance..
    The tyres that are going to offer you maximum Grip (Foams) will get destroyed on every 2nd pass you make down the strip.

    What compound are you running at the moment for the drag strip..
     
  3. billclinton

    billclinton New Member

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    Very cheap leaf pattern tires from ebay, if u do a small burnout b4 u race they get hella sticky, all tires ive tried so far have only lasted 4 passes tops, my best et so far is with the leaf tires, the hpi x pattern second. i have wider formula 1 slicks on the way tho. All my tires are taped. Do u think its too much power? Or tires? Others with similar set ups are going even faster than me? I havent tried foam tires yet.
     
  4. Y2daT

    Y2daT Over Powered RC
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    if the tires are skiping try to incorporate a rear sway bar ... it will help lots ...
    i love foams ... pre mounted ... no taping and way lighter then rubber ... just the switch to foams may mean a higher gear can be run for a faster finish speed ... also try to make the rear tires straight as possible if you have not already ..
     
  5. Magnat007

    Magnat007 Proud SCX10 Owner
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    Foams offer maximum grip but minimum life.. I used to race on a set of foams and I was lucky if they lasted the 7 lap qualifier..
    Also experiment with rolling starts.. see if it happens when you go full throttle after getting the chassis rolling first..
    Just be careful as its not pleasant to watch your RC plow into the concrete gutter
     
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  6. billclinton

    billclinton New Member

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    I am definately gonna try to make a sway bar for it, i think that may help with my issue alot. I have also ordered a set of foam tires and rims. How do u make the rear tires straight on rs4 sport 3? i will keep u guys updated on how it goes. Thanks for the quick responses
     
  7. lout

    lout Studio Forums Elite
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    The tyres hopping are the tyres starting with grip and then slipping and jumping up on the slip and then gripping and then repeat. So good starts are a combination of grip and slip, if you have no slip you will have to build in the "slip" factor. @Magnat007 suggestion of a rolling start is a good one and this will eliminate the need for slip as momentum is king. What you can do, is program a throttle up in the ESC (well some of them anyway) which will start and part throttle and then give or accelerate up to max throttle when you mash the accelerator, allows the car to get going first.
     
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  8. lout

    lout Studio Forums Elite
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    If you look at where the rear lower control arms connect to the chassis, there is probably a block in front and behind the rear diff into which the rods are put. The front block is usually shorter than the rear which would toe in the rear. What you would have to do is replace one of the blocks is a "spare" that matches the one you are keeping. This will straighten your rear wheels and remove the toe in
     
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