I ran 1600kv on my main it was slow as I geared 12t n during my heats I use 16t n was slow. If I run 1600 I hv to gear higher (my heats is 10mins)

It means I may hv to do motor swap during my heats n main

As a former racer....changing motors between heats/mains I found to be personally a PITA...changing pinions is much easier. Find the correct motor so you only have to gear up or down a bit as the track permits

yes i used to change motor but now i change pinion, but i think its overgear for a 1600kv at 19t for 34.5mph, if i use 2000kv i worried abt my 30mins main.

But at 6s i can get 38mph at 14pinion

The joys of racing! The hardest part of racing is balancing performance and runtime

this is my setup n amain videos, i think its slow i m running 6s 5000 with 12pinion medusa 1600kv n 50slip diff on x2 crt.

i was 2nd in 20mins b4 my motor wire got desouldered, its a 25min main(usually 30mins)

its the pinky car with black rims



http://www.youtube.com/watch?v=uCQWdB1FvFw

http://www.youtube.com/watch?v=kDkW3-12eEU
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http://www.youtube.com/watch?v=t1giRI6bJ-Y

http://www.youtube.com/watch?v=tLZQM3lnULQ

http://www.youtube.com/watch?v=WwAvZsHiDpo
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wow i am new and you guys get down with the info , lost me a 5000,6000 lol
some guy is trying to sale me 2 4s 5000 for 120.00 and said to run them in parallel wow lost me at 4s help i just want to run the main rc911

lol, it may be a bit daunting to a newb, but it's not that bad unless you get really deep into it. We're just trying to say that it may be difficult to get 30 minutes on a 4s pack depending on various factors. It's not simply how much mAh your battery has, but the voltage, motor kv, gearing, drive style, weight, etc.

Personally, I was able to get over 40 minutes on 4s 8Ah with a Neu 1512/2d geared for ~40mph, but that was on a buggy. I always felt it was too heavy with those batteries, but I wasn't specifically looking for 30 minutes either.

Be careful about buying used lipos, or if they are too-low priced, unless you know how they were used (or abused). Were they balanced all the time? Were they ever used close to or over their max current rating? You usually get what you pay for. But, two 4s 5Ah in parallel would be 10Ah total. Should be plenty for 30 minutes.

Also, what kind of track is this? Is it big with lots of straights and not many turns? If so, setting it up for ~35-40mph would be advisable. If the track is small with lots of tight corners, set it up for ~30mph because you'll never hit top speed and the lower gearing will be more gentle on your batteries (and increase runtime). No matter what, use gentle throttle to keep the current bursts down.

Any advise guys n Brian? Can I use a amp meter n count backwards to see if it's better on 6s 5000 or 4s 8000?

Short of using something like an Eagletree device, the easiest thing to do is run whatever 4s pack you have at the track you plan to run at and measure the runtime. Then use this page to figure out your power requirements and average amp draw. Post that info here and we can help you choose the proper size lipo as needed.

I hv a amp meter by watts up, n can tell u d amp drawn for both 6s n 4s is that ok?

Unless you can take current samples every 1/10 second or so, it really won't tell much.

it will take d highest amp drawn any good?

Not really. The only thing that will tell you is the C rating of the battery you'll need. Like I said, all you need is the runtime you get, the voltage of the pack, and the mAh of the pack, and plug those values into that link I posted above. That will tell you the average current and power. Then we can go from there.

Sure man u got me all excited I dun feel like going to wrk just go track LOL but luckily my track is closed, they went for femca selection. No Ep:(

should start with my 6s 5000 on 1600kv or 2000kv on 35mph?