Gearing an ERBE for racing on 4s

Shaun, you've got me serious considering 6s, cooler temps sounds great, and while the batts are heavier, as low as they are in my ERevo, it could only serve to lower my CG.

[shaunjohnson]

needless to say because you are running the MMM at 100% and most likely running zippy quality batts...you will need to watch your setup.

like i said...i CANT get 6s power to the ground and the maximum i can pull from my revo geared 17/65 is 70A which is well within both the battery and MMM specs.

cool temps and loads of power are great!!
i did some reading a while back and i hear there is a TVS in the MMM that regulates breaking voltage. this being said, with low quality batts i run (the turnigy cells) i set my breaks to not be able to lock up. locking up the wheels on breaking is bad all round, you put huge load on the ESC and batteries and you cant turn the car with the wheels locked anyway!

having that extra bit of throttle left to pull a rolling wheelie on your last lap as you cross the line is priceless too

Shaun, was that comment directed at me? I'm assuming not since I am running a Tekin T8 and will be getting TP batts, but thought I'd check. It just makes gearing way easier and should help keep my mind at ease... My only concern would be if it's legal to run 6s at my track... they're ROAR compliant. No biggy on the club stuff, but for big sanctioned races, the 6s would be a no go.

[shaunjohnson]

yeah..and there arnt that many good ROAR approved lipo's either that i know of..they should at least approve NEU packs!!
not bloomin maxamps

dont think 6s is road compliant either it should be!!

out club was made around nitro and the electric class was started by me and somehow wormed it's way to have it's own class. but rules are just simple for us and we govern our own rules, gearing must be set to 40mph (to eliminate clear blitzing of each other) and only truggy and trucks are encouraged to race because buggy vs truck is not fair at all whereas well set up truck vs truggy = some kind of chance.

that's how we roll

Hahaha, nice. Yeah, ROAR compliance is tough (to be fair, they're only evaluating packs that are sent to them). I know the 3s TP is ROAR approved, so I may have a work around purely on the fact that I'm running 2 ROAR approved Lipos at one time (I'll have to bug a ROAR rep on that one). I think the only restriction may be that I can't charge them both from a single charger at the same time. I dunno, I'll have to look into it. Either way, I like the idea of keeping my stuff cool. Temps play way too big of a roll on these big 1/8 brushless systems.

[shaunjohnson]

with a little thinking you can charge the 2 packs at the same time...
the charger will see them as a 6s pack.

you will need to make an adapter for the balance lead, so cells 1, 2 and 3 are immediately followed by the other pack's 1, 2 and 3 cells, then rig up a common ground, connect the packs in series with deans adapters etc and you have a saddle pack.

here's the catch those 2 packs MUST ALWAYS be used together no matter what! you wont be able to put one in your rustler and run that, they are always connected as a 6s pack.

Oh, I know that, I was hoping the 4s thing was more of a charging rule from ROAR than anything (not wanting you to charge too many cells at one time). I would prefer to charge them as a 6s, because that means the set is balanced for my E-Revo. Things to consider. I'm thinking I may end up 6s though, if for no other reason that cooler temps.

[SV6000]

Ok Guys i finally got a chance to run my EREVO on 6s. My setup was CC 2200Kv setup, Hyperion G3 3s 5500 bats and geared 18/62. I was running on grass and dirt and it ran fine for about 15mins. I was checking temps regularly and at this point it was motor 140f-160f and speedy about 140f. Than my truck just stopped. I went over pulled the shell off and checked temps again, all good plugged it back in turned it on and it went about 3 meters and puff one MMM turned to ash again
Luckily i had my data logger on at the time and recorded the whole run. The only high point was for 142A but at 3mins in. Nothing out of the ordinary after that.
What the hell is going on. I think i must passion fingers.

[suicideneil]

Bad juju?

Clearly the BL Gods are displeased with you for some reason- if there arent any obvious issues like binding, bad servo, bad motor or bad solder joint etc etc, there really is no explanation- just bad luck

[SV6000]

I had a closer look at the carnage today and realized that it was all around the positive terminal into the speedy. I guess maybe there was a bad solder from the factory or it may have broken during bashing?? The really bad part of all this is that i thought i would ease my sorrows and take out my VXL. that lasted about 3 mins untill one of the motor phases burnt out. The motor is a 36mm 5700, i am not very happy with Castle at the moment. Luckily i had a Hacker 6.5t motor not doing anything so i put that in but the torque isn't there