Expected Run Time

[scott216]

I have a SV27 with two new 4200mAh batteries. How many minutes would be a good estimate to the run time? I had it out the other day and after about 10 minutes (probably a little less), it would not go fast enough to plane off; I assumed the batteries needed to be charged. But when I put them on the charger it showed 7.1 volts, which seems pretty close to full charge to me.

--Scott

[Doby]

10 minutes is more than you should run as it can stress your batteries running them down so low (I assume they are MiMh and not LiPo batteries). 7.1 volts is in an unloaded state on the charger but when you hit the throttle the batteries get put under load and your voltage will be MUCH less.

Full charge should be measured by the capacity of the battery and the voltage, not just the voltage alone. Does you charger tell you how many Mah you put back in the batteries when you charge them.

[scott216]

Batteries are Venom 4200mAh 6-cell NiMH. I probably ran them for less then 10 minutes, but wasn't really paying attention to the time. I wasn't going full speed. I'll have to look at my charger to see if it says how much it charged them. I have a Onyx 240 charger.

[Doby]

Venoms NimH batteries are crap...thats a large part of your problem.

[Grimracer]

ya know.. these silly little batteries give me about 4 to 5 mins and really make the boat run nice

http://www3.towerhobbies.com/cgi-bin...&I=LXNZB8&P=ML

not much money but by-gully work very well!

Grim

[scott216]

I was starting to suspect batteries were not made well. I have 4 batteries and when I use one pair, the boat dies completeley as soon as I give it throttle.

What brands are good?

[scott216]

I was starting to suspect batteries were not made well. I have 4 batteries and when I use one pair, the boat dies completely as soon as I give it throttle.

What brands are good?

[Doby]

You can get good , inexpensive LiPos at Hobby King. NiMh batteries are a dying technology.
Do you have a charger that can handle LiPos?