Low run time on batteries, battery and charger help.

[optikalillushun]

I have a Wheely king thats mostly stock with a Traxxas XL5 ESC, 20T motor and locked axles. I also have the stock battery and an Onyx 6 cell 3000 mih 7.2 battery. Seems my run time is like 5-6 minutes before it slows to like half speed and then another 5-6 minutes then it dies (esc goes into low voltage mode, shuts down the truck). The charger i am using is an old Radio Shack "quik charger" that i had for well over 10-12 years. Now i understand that isnt the best charger to use, so for testing purposes i am using the stock wall charger i got with the WK to charge both batteries and see if i get a longer run time.

Is the charger causing my low run time? the quik charger only seems to charge for an hr to an hr and a half and its done. its odd because it has a lot of juice for the first 5 minutes or so then it slows to half speed.

I am also using the clear/white plastic connectors that came with the truck stock, and from what i read they arent the best. Since i plan to get another charger, which connectors are ideal to use w/o braking the bank because i would need to change them on my Onyx pack and ESC. I also checked the connectors and they dont get warm when charging or during use, so i think im ok now to keep using them until funds allow an upgrade.

I have been looking into the Onyx chargers, particluarly the 245 since it can charge both regular and lipos if i ever upgrade to them. (checked and my ESC is ok for up to 3S lipos). Is the Onyx 245 charger a good choice or are there other recommendations in the price range of $60-100?

And are Onyx batteries good? my g/f bought me the truck and extra battery for christmas last year and i hope she made a good choice. If she did i would like to stick with the same unless i find a good deal on another brand. Suggestions?

[ohh EPiC FAiL]

get the thunder AC6 from hobbypartz.com it's $45 and will charge anything i'd definitely suggest making the switch to lipos as well, just make sure your ESC has a lipo cutoff or you can buy an external cutoff, novak makes one. NiMH is outdated and not very good IMO

[Charlie-III]

The "wall wart" chargers are "OK", but not the best.
There are quite a few reviews/discussions on chargers in this forum.
If there are 20 chargers, you will get 20 opinions.

Make sure it can handle whatever battery you use and hopefully may use down the road. A LiPO capable charger that also does balancing would be good.

Do you have 2 battery packs? If so, do both of them run the same time?
Does the motor get hot?
Does the ESC get hot?
Does your battery get warm while charging? If not, then you are likely undercharging them. This could account for the short run time. Get a better charger and try the same battery, see what happens.

Connectors, at some point the Tamiya connectors will cause you grief. Going to Deans or Anderson Powerpole/Sermos is an upgrade.

LiPO has advantages over NiMH, but I wouldn't say NiMH is worthless.

[optikalillushun]

Originally Posted by Charlie-III

The "wall wart" chargers are "OK", but not the best.
There are quite a few reviews/discussions on chargers in this forum.
If there are 20 chargers, you will get 20 opinions.

Make sure it can handle whatever battery you use and hopefully may use down the road. A LiPO capable charger that also does balancing would be good.

Do you have 2 battery packs? If so, do both of them run the same time?
Does the motor get hot?
Does the ESC get hot?
Does your battery get warm while charging? If not, then you are likely undercharging them. This could account for the short run time. Get a better charger and try the same battery, see what happens.

Connectors, at some point the Tamiya connectors will cause you grief. Going to Deans or Anderson Powerpole/Sermos is an upgrade.

LiPO has advantages over NiMH, but I wouldn't say NiMH is worthless.

Yes and Yes
Warm
Not really
Luke Warm on the wall charger, warm on the rat shack charger.

[Jphillips472]

The onyx chargers are great chargers. The 235 is very sufficient and will charge any battery for about $90. Does the xl-5 have low voltage protect for lipo batts? If it does, turn it off, running nimh you dont need low voltage protection.

[optikalillushun]

Yes it does, ill have to read the manual to see how to. Im not going Lipo yet, just for the future if i wanted to i could with my ESC.

[optikalillushun]

Ran the truck on the onyx 3000mih pack after i gave it a full 6 hr charge off the wall charger. i got about 25+ minutes of run time. that was with a lot of full throttle running. i measured the motor temp, battery temp, connector temp and esc temp.

batt temp - 85*
motor temo - 115-120*
esc temp - 110*
connector temp - 70*

so i think things worked well with the wall charger. ill just use that until i get a good base charger.

[Rxracer]

I like the thunder T610 from hobbypartz. its about 50-60 bux. Charges really well up to 10 amps.
Also if you go that route you will be able to charge lipo down the road when you upgrade.
Rob

[Jus]

Do you have lipo cutoff turned off? That would cause it to cut out so quickly with a nimh I think.

If you want to stick with nimh for now I would go to CheapBatteryPacks - cheap batteries for rc car, Lipo battery and charger, airplane battery and check out the Elite cells built to your voltage and configuration needs. I've had too many cheap nimh packs just die on me..

My first good charger was an Onyx 230 I really like it. I bought it when I started getting serious in the hobby. Knowing it could handle 3s lipo when I was ready. it doesn't have a balance feature but that's O.K. I use the astro blinky balancer with it.

[optikalillushun]

Originally Posted by Jus

Do you have lipo cutoff turned off? That would cause it to cut out so quickly with a nimh I think.

ya know, that is a good question...would it? I will have to re-re-read the paperwork on it.

I gave my Onyx pack a good rundown today and charged it with the wall charger (the one HPI supplies) for approx 6 hrs (max time supposed to charge) and the pack wasnt even really luke warm. hmm, perhaps i should ask my better half for a battery charger for christmas . I guess i dont really need two 12" Infinity subs for my truck, one will suffice

[optikalillushun]

Jus, u were right. I checked on the traxxas site and the low voltage can cut down on run times. Something i need to do.