Results 1 to 13 of 13
  1. #1
    RC poster
    Join Date
    May 2012
    Posts
    3

    Thunder Power 6600 mah 11.1 25c Lipo, why are they so slow?

    I just bought 2 of these Thunder Power 6600 mah 11.1 25c 3s lipos and it seems like my Thunder Power 7.4 5000 mah 2s lipos were ALOT faster!? I took it out only a couple times until I broke my drive shaft try in to adjust it for the weight of the batteries. Well I took it too far down and put a bind on my drive shaft which caused it to break. Did I just waste my money on these new 3s lipos or is there something else that could be wrong. My battery's are in the middle of my battery tray. When I rev'd it out of the water it sure did sound like it had a lot more power than my 2s lipos, but just didn't seem like it at all in the water. Any help or suggestions would be great, and thanks in advance as I'm waiting on my new parts from traxxas.

  2. #2
    RC Qualifier
    Join Date
    Apr 2012
    Location
    Charleston SC
    Posts
    362
    I'm willing to bet your motor coupler failed with the 6s set-up. When running 6s I recommend using the aeromarine 3 piece coupler and at least the .150" Jeff Wohlt Flex shaft. I run the 65c 6s Thunder Powers on my Spartan and they are by far the 'fastest' lipo that I have. Look under some of my posts and you'll find links on where to buy everything.

    On a side note, a 25c lipo is a bit on the low side. Traxxas typically recommends at least a 40c rated lipo on the Spartan.
    E Revo brushless, XO-1, Nitro 4 tec 3.3, HPI RS4

  3. #3
    RC Racer
    Join Date
    Jan 2011
    Posts
    153
    hey anthonyv were does traxxas recommend that cuz the only recommendation i seen was on the spartan product page and it said to get atleast a 5000mah pack so i opted for 6400 traxxas packs only to find out later i need a higher c rating or else i would never wasnt a buck twenty on a pack. I wish i could send these back to traxxas n trade em for some 2s packs,lol cuz there useless!!!

  4. #4
    RC Enthusiast
    Join Date
    Aug 2012
    Posts
    28
    I have been running my spartan on Racers Edge 3400 30c 3s and havent had any major problems other than run time, if i go up to say 6400 40c is it really nessasary to change coupler and driveline? my flex shaft/ liner/ strut are all stock and id hate to break it.

  5. #5
    RC Qualifier
    Join Date
    Jun 2011
    Posts
    965
    The C rating is only part of the equation.
    Multiplying the MAH by the c rating will give you the total max amps the battery can provide without damage to the cells.
    6400 MAH is 6.4 ah.
    6.4 ah x 25C = 160 amps.

    Your 6400mah 25C batteries should be able to supply up to 160 amps without damaging the batteries.

    This should be adequate for the stock spartan, but if purchasing new batteries, it can't hurt to go a bit higher on the C rating.

    This also assumes the manufacturer accurately rates the discharge capability of their batteries.

    Hog

  6. #6
    RC Racer
    Join Date
    Jan 2011
    Posts
    153
    whats the highest temp our packs should be??

  7. #7
    RC Enthusiast
    Join Date
    Jul 2012
    Posts
    20
    Quote Originally Posted by hog View Post
    The C rating is only part of the equation.
    Multiplying the MAH by the c rating will give you the total max amps the battery can provide without damage to the cells.
    6400 MAH is 6.4 ah.
    6.4 ah x 25C = 160 amps.

    Your 6400mah 25C batteries should be able to supply up to 160 amps without damaging the batteries.

    This should be adequate for the stock spartan, but if purchasing new batteries, it can't hurt to go a bit higher on the C rating.

    This also assumes the manufacturer accurately rates the discharge capability of their batteries.

    Hog
    That is a good post hog.

    That really show me why my 3300mah 30c 3s is so much less punchy than my 5500mah 35c 3s.
    Just looking at the "c" rating you could think that they would be close with the 5500mah just giving longer run time but when you look at the amps the 5500 35c battery smashes the smaller one 192.5 amps to just 99 amps that's a massive difference.

  8. #8
    RC Qualifier guardog's Avatar
    Join Date
    Nov 2011
    Location
    Pa
    Posts
    731
    So would this be a good purchase for $64.00. http://www.spcracing.com/index.php?productID=131


    Beatings will continue until compliance is gained

    5400mah 50c =270. $69.95
    8200mah 30c = 246. $ 89.95
    Both are 3s 11.1v
    More power from cheaper battery just less run time Correct ?



    Beatings will continue until compliance is gained
    Last edited by cooleocool; 09-13-2012 at 06:43 PM. Reason: post merge
    uh oh.... that didn't sound good

  9. #9
    RC Qualifier
    Join Date
    Jun 2011
    Posts
    965
    Yes, shorter run times on lower MAH, but the 8200 30C with 246 amps max delivery, should be plenty adequate for the Spartan, if the C rating is accurately represented by the manufacture.

    Hog

  10. #10
    RC poster
    Join Date
    May 2012
    Posts
    3
    So the guy off eBay is letting me return these batteries. What should I get 2s, or 3s. Cause the 3s batteries are a little heavier.
    Last edited by Dadx2mj; 09-12-2012 at 07:03 PM. Reason: Content

  11. #11
    RC Qualifier
    Join Date
    Jun 2011
    Posts
    965
    The seller of the batteries you are inquiring about is banned from discussion here. That is why the editor is blanking out your typing.

    Any of th batteries you mention above should work fine.

    2s or 3s is personal choice. 3s will be faster, 2s will reduce the load on the electrics and should improve reliability.

    Hog

  12. #12
    RC poster
    Join Date
    May 2012
    Posts
    3
    Ok. Well thanks you all for the help!!

  13. #13
    RC Qualifier
    Join Date
    Feb 2012
    Location
    Montreal, Canada
    Posts
    603
    5300mah 60c
    Will this be a good battery for my stock motor?
    I will be receiving soon also my **** motor which I'm setting up on another tray. Which I'm thinking would it work on both motors?
    Sharing is the best thing to do on EARTH legally.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •