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  1. #1
    RC Racer
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    Brushless Sieres Parallel Switch

    Just an Idea I had

    Just Imagine a Mamba Monster set up (as per E-Revo Brushless edition)
    but the batteries are wired into a high current S/P Switch tied to High low range servo.

    7.4V 60C low Range
    14.8V 30C High Range

    potential Problems
    * Finding a switch to handle the amps
    * min Voltage on MM ?
    * will the motor respond well to low voltage heat ect.?

    would be cool I think climb a staicase in low range turn around and launch of the top of them at 40+ MPH high range I want one .

    Any comments on my Idea?

  2. #2
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    I'm not sure how an ESC would react to changing voltage while the ESC is turned on. If that's not a problem, though, it'd be pretty cool. You could even attach your switch to the same servo as the transmission, so switching gears at the transmitter also switched voltage - parallel for low gear, series for high gear. On the other hand, keeping the voltage switch separate would give you effectively four gears - low/low, low/high, high/low, high/high.

  3. #3
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    After thinking about it you would realy need to run NiMh as to not over discharge LiPo's But four gears would be cool, one up from the 3 speed tamiya

  4. #4
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    save that stuff for the future! soon the trucks will be able to hhover over the objects lol jk. it will just be standard for all wheel steering which would be awesome! and hydraulics to lower the car for around turns. not like the normal bouncy hydraulics im talkin to raise and lower ride hieght from controller sounds like an i idea for maybe 09 or 2010. hurry traxxas get the patent! lol
    huked awn fonics werkeded 4 mee

  5. #5
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    I think this might work better with the brushed motor ?

  6. #6
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    A programmable radio and change your throttle "epa". Virtually the same result and still maintains the proper LVC ability of the MMM. We do this for the kids when they want to drive.

    I like that you're thinking of cool ideas!

  7. #7
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    Changing the throttle EPA is not recommended by CC.

    1. I bought the Monster Max system and it's way too fast! How do I "tone it down"?

    Answer 1: Lowest timing advance, smallest pinion and largest spur gear, and experiment with punch control. Always do these three things FIRST. It's not a good thing to dial down the top throttle endpoint, especially when you can re-gear, or just go down in cell count.

    The batts, the ESC and the motor will all run hotter than normal in a system with turned down endpoints to slow it down. The ESC is thermally protected, but the batts and motor are NOT.

    I don't think that means that you can't do it, but it's important to note that it's not recommended.
    Save 10% of the money you make..... you'll never regret it.

  8. #8
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    Quote Originally Posted by aramid
    I'm not sure how an ESC would react to changing voltage while the ESC is turned on.
    The batteries voltage goes up and down when throttle is applied and released, so it should do alright.

  9. #9
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    how about contactors like in pressure switches rigged to a servo i am shure that some of the electronic gurus could build sumthin like that.
    Rusty EVX 14.4V 23T titan
    EMaxx 4.5HvMaxx

  10. #10
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    I have been thinking about it a bit more and think the best way would be to have it all done electronically in the ESC which is a bit out of my league , but if this class,type of vehicle is going to take off Who Knows ???

    Does the EVX II come with learner mode ????
    Last edited by LanceD; 11-08-2008 at 02:07 PM.

  11. #11
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    Yes the EVX 2 has 50% training mode
    Morten SnoopMaxx
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    c",)

  12. #12
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    Sure does.

    On the series/parallel switch- its a non-starter Im affraid, that kind of switching would have to be done via an industrial sized solenoid operated relay switch in order to handle the currents involved. In other words- never gonna happen.

    Bsides, why would you want to drive at 40mph one minute, then 20mph the next- you could achieve said change in speed simply by going easier on the throttle, re-gearing, or dropping a battery pack etc; no need for bizzarre wiring setups....
    Dont consult me, just read the FAQ.

  13. #13
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    Quote Originally Posted by The Oracle
    why would you want to drive at 40mph one minute, then 20mph the next- you could achieve said change in speed simply by going easier on the throttle, re-gearing, or dropping a battery pack etc; no need for bizzarre wiring setups....
    I was just thinking that 7.2V would give you more control in low range (so you would be dropping from 7mph to 3.5mph) as the motor will not be so responsive, also you could get longer run times, Maybe

  14. #14
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    Not really- motors are most efficient at a certain RPM range, so under-volting one wouldnt increase your runtime that way without paralleling the batts which is 99% impossible whilst the esc is turned on, plus if you half the voltage, you would need to gear differently (lower) anyway due to the increase in load from less voltage and therefore power output from the motor. Best thing to do is have a 2spd gear box so you can switch between higher gearing for speed, and lower gearing for crawling... oh, look at that, the summit has a 2spd gear box as standard; how convienient.

    That said, if you wanted to go 'fast' BL, then you go fast all the time, as switching gears from a fastish 2nd gear (30-40mph), to a really low/ slow 1st gear (10mph?) would result in the motor heating up due to severe undergearing. I would say a slower turning large Bl motor would be better, like the KB45 items, as they love to be geared tall; point being, you would run it on 4-6s lipo and have 1st gear as the slow gear (10-15mph), then switch upto 2nd gear for more like 30-40mph, without having to regear or change battery setups etc...

    Its all good, confusing fun....
    Dont consult me, just read the FAQ.

  15. #15
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    Seems a little self defeating if you ask me. I mean this is designed to be an all weather truck, so by removing one of the water proof components, the batteries or the brushed motor, or both, you are defeating the purpose of this truck.

    In fact, much to my disappointment, and joy, I sold by my E-Revo and my Axial Scorpion to replace with one do all truck, the Summit. I look at it this way, I don't race, I don't comp crawl, so why do I have to comp ready rigs? Who knows. I blame the Oracle for all of it actually, talking about super speeds and awesome power, got me hooked. And it had its place, on the track, which I never got too. 45 mph for basing, a little to fast for me, and for my suspension, so screw it, I'm looking forward to going slow again and being able to tackle any obstacle that gets in my way.

    I feel like a freak, getting rid of my BL and LiPos to go back to NiMh and Brushed motors, but, such is life. I can't wait to drive in the rain, snow, mud, rocks, rivers, streams, and whatever else I can find for the Summit to tackle.
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  16. #16
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    Sorry if I am flogging a dead horse here but the only thing I can compare to was a brushless mini -t I had, with a 7.4V lipo the motor was super controlable at low revs with a decent top speed, with a 11.1v lipo it was a rocket ship but there was no drivability at under half throttle, I realise this is by no means a fair comparison with the size and motors KV differance.I really can't see me changing anything on the summit when I do get it. I am just trying to open the mind a bit and throw idea's in the ring (I realise this one is out there LOL!) but I am a speed adict (RC type of corse) and I would love for this thing to hit more than 20-25 MPH in top gear. Although that is what my race cars are for.

  17. #17
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    Anyone consider a 7t Cobalt Puller motor? It's used in high powered rock racing rigs. I've found it for about $80 on some sites and it really powered the AX10 rock racers that I saw. If anyone can give me some info on it, that would be great.

    Be right back, getting the link.

    http://holmeshobbies.com/product.php...3&bestseller=Y

    Let me know what you think. Could be great on paralleled batteries, long run times and half way descent speeds.
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  18. #18
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    Why not just go with the Kershaw setup, one 775 or the twin 775's.

  19. #19
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    The Puller 7T is designed to run on 7.4v-11.1v, which means that you could run it off the batteries when they are wired in parallel which would in turn give you double the runtimes off of the NiMh batteries.

    Or you could run two of the motors in series, like the E-Maxx does and put enough voltages to each motor so that they are running at optimum RPM all the time. Way more low end power and control.

    Just thinking.
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  20. #20
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    The emaxx motors are wired in parallel, they draw double the current from the batteries that a single motor would. If you wire them in series, you draw get half the current draw, but also half the speed ( a motor is basically a resistor ).

    I think the single 775 motor will have more than enough grunt, otherwise look at a pair of 540 lathe motors- something like 35-55turns, and run them from a pair of paralleled 2s lipos or 7 cell nimhs.

    However, I dunno where this notion that lipos arent waterproof and nimhs are came from? Nimh packs arent sealed any more than a lipo pack is, so water will enter the open ends of the packs and get trapped, corroding the connections and rusting the cells/ tabs. You can seal a lipo pack very easily with some silicon sealant or plasti-dip, just leaving the wires poking through at one end, and sealing the gap around them & into the pack.
    Dont consult me, just read the FAQ.

  21. #21
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    Quote Originally Posted by FireWire79
    Seems a little self defeating if you ask me. I mean this is designed to be an all weather truck, so by removing one of the water proof components, the batteries or the brushed motor, or both, you are defeating the purpose of this truck.

    In fact, much to my disappointment, and joy, I sold by my E-Revo and my Axial Scorpion to replace with one do all truck, the Summit. I look at it this way, I don't race, I don't comp crawl, so why do I have to comp ready rigs? Who knows. I blame the Oracle for all of it actually, talking about super speeds and awesome power, got me hooked. And it had its place, on the track, which I never got too. 45 mph for basing, a little to fast for me, and for my suspension, so screw it, I'm looking forward to going slow again and being able to tackle any obstacle that gets in my way.

    I feel like a freak, getting rid of my BL and LiPos to go back to NiMh and Brushed motors, but, such is life. I can't wait to drive in the rain, snow, mud, rocks, rivers, streams, and whatever else I can find for the Summit to tackle.
    I am looking at the Summit in the same way you are it seems also.

    I can go to a cool track with my Slash now, but 45 minutes away one way. Won't have the time though to get into the racing thing they do there though. Will take up the whole day. They mix things up, and not yet just a Slash thing, but he wants to try and get it it going with the interest people have with the Slash. I did go there one day just to play on the track, and spent 5 hrs just there playing by myself. With driving to and from, it became a 7hr day with just that. Had fun though. LOL

    The Summit thing for me also is, being able to just go out wherever and play, without having to get to a track.

    Also, with the Summit, I am not interested in super speeds. I like the fact with the Crawling aspect of it, you can be up close to it and see the Truck work and move and all. The Summit will be something that has this combination of things going for it. Will be able to spread out into different conditions, and just plain enjoy it all.

    So, with getting the Summit, and having the Slash, I will now have a good combo of things to enjoy. For the Track and for the Boonies. LOL

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