4 cells on a 6-7 esc only
 

This is very important. I use to run a super rooster on 4 cells for a bit but then something happened and it stopped working. i don't know if it's because it's not ment to br run on 4 cells or something else. Now i'm buying a new ESC to use in my 12l3 and was considering the novak fusion. I also says you should use 6-7 cells with it. Is the ESC going to get runined if I only use 4 cells? What's the worst that can happen? Does it really matter any way, it's not like i'm using to many cells then recommended. is the warrenty voided if i use 4 cells?

Re: 4 cells on a 6-7 esc only
 

I'm unsure of the warranty ramifications, but if you run a receiver pack, you shouldn't have any problems. Of course you could always get a speedo that's designed to handle 4-cells like an LRP Quantum Sport, a GM V6 or Mtroniks Sprint, all are about the same price range as the Fusion but are designed for 4-cell and up usage.

it should work!
running 4 cell is like running a little bit dischaged 6 cell pack

It's not like running a little bit discharged 6cell pack, it's running at 4.8v instead of 7.2v, if your 6 cell pack reaches 4.8v when running it will be heavily discharged. Some speedo's are capable of running on 4.2v and they will usualy say so in the specs, others just won't work at all, so it's best to get one thats got the specs you need.