two battery questions

[DyrtyByrd]

i have two Qs i have two turnigy 2s 5000mah 30c lipos that i use for my stock ul1
i hit them with my temp gauge after my run today and one was 100 deg and the other was 125 deg why such a big gap does this mean one of my batts are bad?

i also have a zippy 3s 2200mah 25c that i use in my rio with a 60 amp tunigy speedo fully charged plug it up and about 5sec into the run it hits the low volt cutoff bring it in and check the volts and its 4 volts on each cell i have two more of the same batt except they are 30c that i run with no probs any ideas? thanks for any help

[LiPo Power]

25C should not be the problem.
How old is your zippy on rio? Did you use it before and it was fine? What is the cut off set to on esc?
looks like its no longer holding up under the load....

[785boats]

With your first question...
Are the batteries the same age & always been used as a pair, ie discharged & recharged at the same time & rates.
If not, they could have developed different internal resistances which cause different discharge rates under load.
Next time you run them check the cell voltages at the end of the run & see if the hotter pack has lower voltages.
I always parallel charge my pairs of 2s packs & always keep them in the same pairs.
That way they start out with the same voltages & capacities.
At the end of the run the voltages & temps are as 'near as next to makes no nevermind'. As my dear grandma used to say.
Cheers.
Paul.

[Brushless55]

are you running the packs down to the LVC in your UL-1 ?