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  1. #1
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    Cool Twin 775 set-up on demand…

    I know the twin 775 is nothing new but Im adding a neat twist if I can get it to work properly…. what im doing and I hope the Enhanced image below gives a better idea.
    I am working on drafting a plate that I can run 2 motors on the same side so it will fit with my low profile cage. The placement of the motor leaves some space below for me to put in a solenoid or switch that will only enable the second motor when you engage low gear. This is my initial concept… I figure when im pinning the throttle for a jumping or bashing, im not killing the batteries as bad…however when I really need that torque for pulling or crawling and switch to low gear I the 2 motors will engaged

    LONG TERM - my finial concept is once I can find all the required components will be a remote switch system that will give me the ability to control if I want to run motor 1 or 2 or both…

    I will try to keep posting as i go through the process and hope I can carry out this idea....it would be neat to be able to call on the power when needed or switch between motors to help them not overheat…

    Quick pick to show layout…

    Just do it...they make replacement parts.VXL power

  2. #2
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    thats an awesome idea. It will be difficult to actually make and achieve but once you do, Thats going to be sick! You could possibly even patent the idea/design. Keep the thread updated!
    SlashVXL-ERBE-Slash4x4PE-RustlerVXL-1/16SlashSW2

  3. #3
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    You will have to disengage one motor completely to use only one motor. The drag on the dead motor will seriously effect the other motor.

    Having 2 x 775 Titans for crawling will also not help that much with torque. The one motor already give plenty of torque.

    The design will only really be of benefit if both motors are being used all the time.

    Just my 2c.

  4. #4
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    I second that drag concept. If you ever turned a high torque motor by hand then you can imagine how much that dead motor will tax the live motor if it is not powered. An idea maybe a strong servo that can push (rotate) the motor up and disengage it from the spur gear when driving in high gear, then allows it to drop back down into place when you are in low gear.
    MAN, Use Common Sense
    Funky Gecko, SumVee HDE

  5. #5
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    Go with the dewalt set up. Much more easy to install,more power than prolly both 775's, less work to do.
    No you cant drive it
    my RC is owner operated only

  6. #6
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    Quote Originally Posted by noir 522 View Post
    An idea maybe a strong servo that can push (rotate) the motor up and disengage it from the spur gear when driving in high gear, then allows it to drop back down into place when you are in low gear.
    Thats what I was thinking after reading that post by christo... Maybe using a solenoid to lift the motor away but instead and instead of using the hi/lo gear using the "both diff lock" funtion as my trigger to engage the second motor helping to plow through anything in hi or low gear....
    Last edited by mdlopez1; 12-22-2010 at 08:46 AM.
    Just do it...they make replacement parts.VXL power

  7. #7
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    Possibly a one way clutch setup on the dead motor , this way less drag when its not in use.

    keep pushing you'll find away


    Light bulb just flashed, after reading your reply. the answer might be there. a Diff lock. but use a extra diff lock setup on your motor pinion . this way can engage and disengage that extra motor when needed.
    Last edited by VonGearStripper; 12-22-2010 at 12:54 PM.

  8. #8
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    Will the extra weight of the extra motor cost more than you gain in high gear your still carrying the weight but getting no benifit.
    Or "Is the juice worth the squeeze"although just making the idea work is worth it just so you can be satisfied knowing i made it work.Plus i haven't seen it done before.
    Von may be onto something there.Would still want to cut power to that motor though what would be really cool is a way to feed the front and rear diff's independantly would make a dig alot easier .dual transmission maybe
    Mountains cant stop me
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  9. #9
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    Sounds like a Rube Goldberg way of getting the same power of 1 Dewalt. Never mind that the Dewalt can also handle 5s lipo voltage, 775 can't, for serious power.

  10. #10
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    Although I currently do not think it is worthwhile or that it will work I still feel you must keep on thinking about it. It will be a very interesting project and you could come up with a brilliant idea to solve the issues.

    Do not see my reply as negative. I just would like the final solution to be really mind blowing.

    Just something else to remember. The extra torque will only be of use if the weight and the traction of the truck compliment it. In a difficult situation without the weight the wheels will turn but the truck will not move.

  11. #11
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    I agree it is simpler and much more battery efficient to just stick in a dewalt, but this is a hobby (read be creative) so just plan carefully and keep us updated on your Twin Titan monster.
    MAN, Use Common Sense
    Funky Gecko, SumVee HDE

  12. #12
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    Going to do more research but think I will hold this idea since i'm not getting much bang for my buck...

    Status:

    Completed plate simple to create but extremely disappointed with performance... I picked two markers in a parking lot and timed them one motor did the run in 8.26 seconds 2 motors did the same run in 8.08.

    single motor had about 24 min run time
    dual motor ran about 16 min

    based on: ( consistences)

    Ran in "ovals" until motor stopped
    Kept throttle pinned and did wide sweeping turns to keep up momentum
    used same series-4 8.4 volt traxxas batteries ( newest set only about 2 runs on them)
    did runs 1 hour after batteries were fully charged
    Gearing 18/56
    on hi gear with no diffs engaged


    Im going to wait on this project until I find/can afford a larger esc and motor set up... I think its a great concept that just needs to be developed further... feel free to keep posting ideas and thoughts I will post mine on this idea as this project progresses.
    Just do it...they make replacement parts.VXL power

  13. #13
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    I did not think the speed will improve dramatically. I believe the torque did improve quite a bit.

    Battery run-times is as expected.

    You should not be disappointed with the results. These where expected. My mind is also now running around the hows and whats.

    I am currently in Saudi Arabia on holiday and can not wait to get back home to do some design of my own around this.

    My idea would be a tranny between the second motor and the spur that can be engaged with a small servo.

    The other idea is to have one motor drive the front wheels and the other motor drive the rear wheels. This would completely change the drive-train of the Summit and would call for a new name for the truck.

    Keep on thinking and keep us in the loop.

  14. #14
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    Kershaw dual motor set up (kershaw motors are in the same titan 775 - mabuchi family with slighty different wireing for more speed) had a top speed of 28mph (compared to the stock summits 22mph) . But it appeared top heavy and I am sure it lowered the battery-run time. But the torque must be insane.
    MAN, Use Common Sense
    Funky Gecko, SumVee HDE

  15. #15
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    Another thing to keep in mind if you don't actually disengage the motor from the spur gear: The second motor will be spun by the first motor, and act as a power generator. It will send power into the ESC "from the wrong end", and eventually fry it.

  16. #16
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    Correction on my gearing.... It's 23/56 not 18/56 as indicated....


    After reading posts I will continue and maybe create a prototype that others can build off of.... Thanks guys
    Just do it...they make replacement parts.VXL power

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