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Old 03-02-2011, 09:52 AM   #2356
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The problem lies at the input caps. If you have a higher resistance battery under heavy load there is more ripple on the input voltage and the caps will overheat. You can minimize this by gearing down a bit and monitoring the ESC temp. My first ESC died and had never seen 120F.



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Originally Posted by macnkitty2002 View Post
Wouldn't a higher C rating make the ESC run hotter? Or do low C ratings make the ESC work harder to pull current from the battery?

Maybe it's that with a higher C rating, the ESC has more power on tap from the battery and doesn't have to 'pull' as hard on the battery.
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Old 03-02-2011, 10:45 AM   #2357
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There is something called "ripple current".Here's is a quote from Castle's email (I asked about Mamba Max before about 2 years)
"Too low of capacity and you can damage the ESC from ripple current (big voltage swings going into the ESC)."


"When the batteries cannot handle the current the system is trying to draw it induces ripple current. Ripple current causes more ESCs to fail than anything else. This phenomenon takes place when the ESC is switching on and off thousands of times per second. The batteries obviously cannot do that so the capacitors store a charge to get the ESC through this, and smooth the current and voltage out. If the batteries cannot provide enough voltage/current to keep the capacitors charged, the caps keep trying to dump but there's nothing in them...they get hot, and if they get hot enough the electrolytic fluid inside boils and the cap fails. When this happens your ESC is open to those huge current swings and it'll go up in smoke. "

You must have a battery than can give more amps than your motor is pulling.Otherwise your esc will fail.
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Old 03-02-2011, 11:30 AM   #2358
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If you have a video fo your OFNA ride on Youtube please send me the link so I can review and maybe post it on our OFNAfan.com website. We wanna have bashers,crashers and racers in their OFNA's tearing it up. Bring it, Titans, DM-1's, GTP's, Dominators, Pirates or even old school Colts if you got a vid send it to me at DJ@ofna.com.
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Old 03-02-2011, 12:53 PM   #2359
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Regarding batteries, I was informed that the C rating is pretty important but the discharge rate total (Mah x c) is really what you're looking for.

I only have 20C lipos for the Savage Flux but they're 8000Mah (160 amp discharge) and its been going for over a year now. So technically 20C lipo's will do the job if the discharge rate is ample. Yes 25, 30 or even 40C batteries would be even better but I'm just saying thats not the whole picture.
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Old 03-02-2011, 02:35 PM   #2360
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So Im thinkin the verdict is either the sct 3800 or the dynamite 3300....buyin it this weekend no matter what....I have two 4000mah 25c lipos will these be enough or do I have to goto 40C????? also if anyone can reccommend a less expensive servo that will be good...I would appreciate it
OK well cant find the sidewinder SCT 3800kv in stock anywhere....so gonna pray it comes in soon....anyone got an idea for the servo type and what size batts to use?????
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Old 03-02-2011, 02:39 PM   #2361
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OK well cant find the sidewinder SCT 3800kv in stock anywhere....so gonna pray it comes in soon....anyone got an idea for the servo type and what size batts to use?????
ebay
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Old 03-02-2011, 02:47 PM   #2362
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Quote:
Originally Posted by scooterman19 View Post
OK well cant find the sidewinder SCT 3800kv in stock anywhere....so gonna pray it comes in soon....anyone got an idea for the servo type and what size batts to use?????
A few servo choices...any good servo over 120oz would be good...the speed is up to you under .20 would be best

economy- EXI D226F from hobbypartz $15 180oz/ .15sec

good- Traxxas 2075 $20-25 on ebay 125oz/ .19 or .2sec ???

better- Savox SC-0251 $40 222oz/ .18sec

best- Savox SC-1256TG $80 277oz/ .15sec

For the battery.....if you go with the Castle SCT a minimum of 4400mah 25c
I have some 5200 30C Turnigy LIPO's from hobbyking and they seem to be working very well
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Old 03-02-2011, 03:13 PM   #2363
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I have the Savox 1258, it is a great servo for this truck. real fast and torquey. They have a $20 coupon deal right now make it under $50 (savox direct) Coreless, digital, Ti gears and AL case
Speed(@6.0V sec/60): .08
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Old 03-02-2011, 03:24 PM   #2364
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Originally Posted by utah300rum View Post
A few servo choices...any good servo over 120oz would be good...the speed is up to you under .20 would be best

economy- EXI D226F from hobbypartz $15 180oz/ .15sec

good- Traxxas 2075 $20-25 on ebay 125oz/ .19 or .2sec ???

better- Savox SC-0251 $40 222oz/ .18sec

best- Savox SC-1256TG $80 277oz/ .15sec

For the battery.....if you go with the Castle SCT a minimum of 4400mah 25c
I have some 5200 30C Turnigy LIPO's from hobbyking and they seem to be working very well
thanks for the servo info....do you use the castle SCT???
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Old 03-02-2011, 03:47 PM   #2365
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What is a general track shock oil setup for this thing? My truck seems to slap on even some small jumps. I bought my truck secondhand and I'm not sure what the guy had in the shocks, but it feels like its in the 30 range. I'm running the orange springs up front and blue in the rear.

Is there anything I can do to get some stiffer damping? I know it's not going to be plush like a 1/8 buggy and it is heavier than the average 1/10 electric buggy. Do shocks from any other vehicles work on this?
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Old 03-02-2011, 05:36 PM   #2366
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Quote:
Originally Posted by macnkitty2002 View Post
What is a general track shock oil setup for this thing? My truck seems to slap on even some small jumps. I bought my truck secondhand and I'm not sure what the guy had in the shocks, but it feels like its in the 30 range. I'm running the orange springs up front and blue in the rear.

Is there anything I can do to get some stiffer damping? I know it's not going to be plush like a 1/8 buggy and it is heavier than the average 1/10 electric buggy. Do shocks from any other vehicles work on this?
I know nitrohouse had a setup on their website with somethin about adding another hole on the shock piston or whatever its called lol...still learnin about shocks but I know its on there

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Old 03-02-2011, 06:34 PM   #2367
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Quote:
Originally Posted by macnkitty2002 View Post
What is a general track shock oil setup for this thing? My truck seems to slap on even some small jumps. I bought my truck secondhand and I'm not sure what the guy had in the shocks, but it feels like its in the 30 range. I'm running the orange springs up front and blue in the rear.

Is there anything I can do to get some stiffer damping? I know it's not going to be plush like a 1/8 buggy and it is heavier than the average 1/10 electric buggy. Do shocks from any other vehicles work on this?
I'm running 35f and 30r on mine with the orange springs all around and it works very well on big jumps and small. Since you got it used, you might want to take the shocks apart and see if the pistons are still on the shaft. A guy at my track had the e-clips come off his and had to replace the shafts.
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Old 03-02-2011, 06:41 PM   #2368
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what am i doing wrong?

Trying to rebuild my shocks and i cannot for the life of me get them to rebound the same. unless its full rebound.

I've never had this issue before and have built them numerous times.

I had to walk away from the bench!
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Old 03-02-2011, 08:40 PM   #2369
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Quote:
Originally Posted by scooterman19 View Post
thanks for the servo info....do you use the castle SCT???
yes I have the SCT in my 10TT...so far so good, racing season hasnt started yet...but for our track (tight, technical, low traction) it is working well.

I have the stock spur with a 13T pinion now, running cool, but a little harsh on the bottom end....I am going to try a 14T on my next practice session.

I also need to get my Castle Link running and try to tone it down a little on the bottom end...Anyone have recommendation on their SCT settings?
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Old 03-02-2011, 08:44 PM   #2370
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a few guys at our track in mid tennessee have these and while they're not racing them in a class they still look awesome. i'm not a huge fan of the body but the rest of it is so clean. i might have to pick one of these up if the class takes off
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