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  1. #1
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    rx8 questions and waterproof

    So after a mishap with a hobby wing brushless system, I took a deep breath and dove into the gen 2 rx8 and t8 2250 sensored system and I was wondering, how butter Smooth this thing is supposed to be? It still cogs slightly with very little throttle input. I thought it would be smoother than this? Am I expecting too much or did I miss something? Also does anyone make water resistant cover or over tray type thing to let me have some Fun on the days it's a little less than dry? Not looking to plastidip at least till my warranty is up.
    Its a Summit thing, you wouldn't understand.

  2. #2
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    Did you re calibrate the tx and Rx
    After the switch?
    Outerwears or dusty motors both make splash resistant chassis covers.


    Sent using lipo power
    Mountains cant stop me
    they have tried

  3. #3
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    Is the sensor wire connected properly? It should be very smooth with no cogging. At least my Gen1 RX8/T8 2250kv motor was.
    Slash MT, 1/10 Summit.

  4. #4
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    My gen2 does the same thing, it's not as smooth as I thought. I'm coming from the dewalt motor and stock esc.

    I'm thinking it might be all the settings we can adjust? Can anyone give us some insight on what settings we should tweak?

    Thank!


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  5. #5
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    By calibrating tx and rx go you mean setting the end points and neutral zone for the esc?
    Its a Summit thing, you wouldn't understand.

  6. #6
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    A brushed motor has always been a little smoother to me than sensored brushless motors. Perhaps it's due to the way power is delivered, and the way both motors function. The brushless motor has to have power cycled through the phases constantly, where the brushed motor just needs direct current (and handles changing the polarity itself).

    I've also noticed that the ESC has a direct effect on how smooth the sensored motor is. To me, an RX8 and an MMP have a different feel on the low end.

  7. #7
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    My MMP and 2350kv motor, with 22t pinion and 65t spur, has no cogging.

    I would double check the calibration to the tx/rx =)

  8. #8
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    I know castle has a "start power" in its programming if the rx8 does make sure it is at the lowest setting also try a different sensor wire and make sured your esc is in censored mode.

  9. #9
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    Still having problems going very slow. I've watched some videos of others with the same setup and mine is definitely not working the same. I turned "punch control" all the way down, checked where the sensor wires plug in at for debris, followed the setup for the esc over again not sure what I'm doing wrong. One thing I did notice is the fan isn't always on and the middle led is the one that stays on (I thought the first one was supposed to be on to show the temperature of the esc in stages) and sometimes it flashes over to the first or second led then goes right back to the middle. And how do I know I'm in sensored mode? I don't think it gives me a choice just brushed or brushless.
    Its a Summit thing, you wouldn't understand.

  10. #10
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    To check sensors , spin pinion in hand slowly, last 3 leds(5,6,7) will flash in sequence (just a faint flashing).
    You should see this sequence if everything is right:
    5
    5+6
    6
    6+7
    7
    7+5
    and again.

    That cogging with very little throttle input. It is not cogging, mine does exactly the same. It's a point where the motor starts to move the car at all. And as Summit is heavy car it may seem like cogging.

    Here I found answer from tekin directly http://traxxas.com/forums/showthread...=1#post5204591

    Punch control(current limiter on tekin) has nothing to do with smooth slow start. It limits wheel spin when full throttle is applied from standing still(by rising current to motor gradually in first second or so) . What you need ti change is throttle minimum.

    ESC is always switching between middle led and and temp scale. At idle is just led 1 when driving it maybe anything from 1 to 7, When 7 is reached esc will shutdown to lower temps. Fans is triggered by esc when needed by default. IT spins for a second when powered up to let you know it is OK.

    RX8 works in dual drive mode. It stars as sensored and then switch to unsensored mode at higher speeds. Its all in tekins FAQ on their page. If you want brake and reverse you only option is motor type 3.
    Last edited by Marek_K; 03-06-2014 at 04:12 AM.

  11. #11
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    And I'm guessing the throttle minimum can only be changed via hotwire.
    Its a Summit thing, you wouldn't understand.

  12. #12
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    Hot wire is a must, at least you need to change Lipo cut off. Default is 3V and that is waaaay to low for modern lipos. I set it to 3,3/cell. It takes 5% of ride time off at most but lipos will last much longer at that cut off.

  13. #13
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    Well the hot wire is on the way then. I think another part of my problem is the slop in my transmission if it was tighter I think the cog would be less noticeable. I guess the new firmware is supposed to help with cogging too.
    Its a Summit thing, you wouldn't understand.

  14. #14
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    Sorry I was wrong, that cut off is 3,2V by default now, but anyway set it to 3,3-3,4V. Slope in transmission has nothing to do with cogging. I always download newest firmware, but did not noticed change whatsoever.

  15. #15
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    Slop does have a lot.

    The motor will "cog" trying to move the car forward, but the slop will provide a kick back, making it constantly kick back and forth UNTIL it locks up, once you move you shouldn't be cogging anymore, but if you slow down from the slow speed you are already doing, it will happen again. That TECHNICALLY isn't cogging, but it is the same type of motion.

    Happens on my machine, but once the car starts moving - as in a foot every 10 seconds - it goes away, but UNTIL it moves it happens.

    COGGING happens even when the car is moving, and I doubt that is happening to you based on what you've said.
    Last edited by krallopian; 03-07-2014 at 12:33 AM.

  16. #16
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    Any good ways to fix the slop in the transmission that Will hold up to brushless power?
    Its a Summit thing, you wouldn't understand.

  17. #17
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    Got my hot wire and it runs great now thanks for the help. Is there anywhere that I can get the small screws that hold the esc together. I'm my attempt to separate the case to plasti dip my esc I stripped out the head of one of the screws. Decided against the cover due to temp issues.
    Its a Summit thing, you wouldn't understand.

  18. #18
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    I have the hot wire on the way. What exactly did you do to help it? Can you fine tune the esc more with the hot wire than you can directly on the esc?

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  19. #19
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    The hot wire gives you fine tuning and custom settings. Plus there are a few other settings you can't get to without it. I lowered the throttle minimum to one and now it crawls beautifully even with the slop in the transmission. Current limiter you should set to your preference but it helps from too much power at once and blowing out parts. Brake control I set to about 35 otherwise full brake makes for some awesome front flips and more broken parts. I have the cable to run it from my android device and the app for my phone. It makes tuning that much easier when you can adjust and test accordingly.
    Its a Summit thing, you wouldn't understand.

  20. #20
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    Quote Originally Posted by wheeler313 View Post
    The hot wire gives you fine tuning and custom settings. Plus there are a few other settings you can't get to without it. I lowered the throttle minimum to one and now it crawls beautifully even with the slop in the transmission. Current limiter you should set to your preference but it helps from too much power at once and blowing out parts. Brake control I set to about 35 otherwise full brake makes for some awesome front flips and more broken parts. I have the cable to run it from my android device and the app for my phone. It makes tuning that much easier when you can adjust and test accordingly.
    Can you post a vid of your truck, at crawling speed, with those setting, please? i'm still trying to get the best tunning!
    Summit RX8/1550kv-Slash4x4 MM2/2400kv Twin-V Merv.

  21. #21
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    Boilo do you have hot wire? If so I think there's a way to copy my settings thru the driver profile setup.
    Its a Summit thing, you wouldn't understand.

  22. #22
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    Oh and I'll get on that vid spc 8200s take a while to recharge.
    Its a Summit thing, you wouldn't understand.

  23. #23
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    That's cool man! And yes i have hotwire!
    Summit RX8/1550kv-Slash4x4 MM2/2400kv Twin-V Merv.

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