RCCrawler Forums

The Violator · 09-18-2010, 03:25 PM

I have wanted more battery life in my 4pk. I have been running the Trinity pack with success. But I still wanted a lipo. But with me being so cheap, I wanted to try it before I had to spend any money. I had an old 2200 3s lipo (cycled it and charged it to 2700mah). I went rogue and cut it apart and removed 1 cell. Now I had a 2s lipo. I did not put ballance taps back, but I do plan on ordering another pre made lipo if I end up liking this. I went with a Castle BEC, because in the end anything that has to do with a crawler needs a BEC!!!! I set the BEC at 6.5 volts. It should stay at 6.5 until the battery gets low and once it drops below 6.5 I will know I have some time left before I damage the lipo but should think about getting it charged soon.

The only draw back I am seeing is that I have to unhook the bec every time I am done to keep it from killing the lipo. I hope it has more life than a comparable standard pack, but that is yet to be seen. I am not sure its any lighter, but again I am hoping to get several hours of runtime. I am going to just leave it on the rest of the day to see how long it lasts.

I will keep an eye out for a small switch to use inline with the battery to eliminate having to unhook the battery everytime I am done. The local radioshack had nothing small enough for me.

EDIT:

After reading 4xfords post I went buckwild and tore into my radio. I ran a wire up to the left side and added the smallest switch I could find. I switched the negative side of the BEC feed. I do not have to remove the battery cover to remove power from the BEC.
I also took out the stock battery tray and there is a bunch of room now. I can fit a 5000 Hyperion in there, but that battery is the best one I have for my slash so for now I have lots of room with the 2200 I have. I will have to look for something in the 4000 range.

This one was taken before I tightened the screws back up

Sharkey · 09-18-2010, 04:17 PM

you can always rewire the radio to bypass the original switch, then run wires from the switch to between the battery and bec. that would give you a factory switch and not needing to unplug the battery.

The Violator · 09-18-2010, 04:19 PM

Quote:

Originally Posted by Sharkey

you can always rewire the radio to bypass the original switch, then run wires from the switch to between the battery and bec. that would give you a factory switch and not needing to unplug the battery.

Thats a great idea. Does anyone know if the switch is separate, or mounted to a circuit board.

treadway47025 · 09-18-2010, 05:23 PM

I dont understand why you need a bec in a radio controller unit.

jason · 09-18-2010, 05:34 PM

Quote:

Originally Posted by treadway47025

I dont understand why you need a bec in a radio controller unit.

The reason he has it in there is to make sure he doesn't give too much power to the radio.

I could be wrong, but I think some people are running 4pk's directly of 2s lipo.

Duuuuuuuude · 09-18-2010, 06:00 PM

I did the same with my React...works great. I hid the BEC in the handle so there would be one less thing to stuff into the compartment.

The Violator · 09-18-2010, 09:43 PM

Quote:

Originally Posted by treadway47025

I dont understand why you need a bec in a radio controller unit.

I think the radio has an over volt shutdown at 8 volts ( read that somewhere, I could be wrong). The 2s lipo when fully charged is 8.4 so unless I wanted to run it at less than a full charge the BEC was needed. My goal is extra run time so running it at less than a full charge would not be an option for me.

4xFord · 09-18-2010, 09:52 PM

Nice work Ted.

I run a cc bec and a zippy 4400 mah 2s lipo. Just get used to unpluging everything at the end of the day. My radio is heavier than stock but that doesn't bother me at all. I love the ridiculous runtime it has. I ran 2.2 LCQ, 1.9, super, and 2.2 on the same charge. I leave mine at 7.1 volts so that I have a good buffer before running to low.

The Violator · 09-19-2010, 12:08 AM

Quote:

Originally Posted by 4xFord

Nice work Ted.

I run a cc bec and a zippy 4400 mah 2s lipo. Just get used to unpluging everything at the end of the day. My radio is heavier than stock but that doesn't bother me at all. I love the ridiculous runtime it has. I ran 2.2 LCQ, 1.9, super, and 2.2 on the same charge. I leave mine at 7.1 volts so that I have a good buffer before running to low.

You got a part number for than 4400 lipo. That would be exactly what I am looking for, just everything I looked at was much to big. I am going to strip off the wrap on my radio and take it apart to try to fit the BEC in the handle and put a switch on the left side of the radio. Good luck to me.

4xFord · 09-19-2010, 12:47 AM

Quote:

Originally Posted by The Violator

You got a part number for than 4400 lipo. That would be exactly what I am looking for, just everything I looked at was much to big. I am going to strip off the wrap on my radio and take it apart to try to fit the BEC in the handle and put a switch on the left side of the radio. Good luck to me.

I don't but I may be able to find it on the site. It was a hard case pack that I bought two of. I had a hunch that the cells would fit without the case and I punctured one on my first try of opening one up, learned my lesson and got the second pack open damage free. They were 20c, other than that I can try to help you out with dimensions. Also, I removed the stock battery tray from the bottom of the handle before I ever even powered up the radio...

EDIT: ya I can tell from your pic the stock battery tray is still there. I will get some pics of my setup for you tomorrow.

The Violator · 12-17-2010, 10:27 PM

A little update. I took a 4000 4s lipo and split it up. I have been running the same battery since Late September. Many comps, many track nights with my Losi 8ight t and slash, and just ran the battery down tonight. About 3 months without having to mess with a battery. I would suggest to anyone looking for a longer runtime try this out.

Rootar · 12-17-2010, 10:48 PM

you know they make 2s Life packs just for the 4pk. no BEC, no mods, just plug and play

( you can even charge it with your dinky wall charger if your too lazy to hook it up to your real charger)

here ya go
http://www.allerc.com/hyperion-lifepo4-2080-mah-6-6v-transmitter-pack-p-4724.html

The Violator · 12-17-2010, 11:47 PM

Quote:

Originally Posted by Rootar

you know they make 2s Life packs just for the 4pk. no BEC, no mods, just plug and play

( you can even charge it with your dinky wall charger if your too lazy to hook it up to your real charger)

here ya go
http://www.allerc.com/hyperion-lifepo4-2080-mah-6-6v-transmitter-pack-p-4724.html

That would work if it was 4000mah. I have a 2200 pack that was a drop in, but it would not make it more than a week.

Scottmisfits · 12-19-2010, 08:58 AM

I have 2200mah LiFe from Trinity and I can get a litle over 30 hours out of it. I charge my radio batteries really low though. Instead of the 2.2a charge rate that they say is safe to use, I use a charge rate of 0.2amps. It takes quite a while to charge and it is a paint in the ass to charge on my charger because of the over capacity shutdown sfaety feature but it's worth it. I hate being at the track or the crawling course and having my radio go dead while I need to charge other batteries as well.

09-18-2010, 03:25 PM	#1
The Violator RCC Addict Join Date: Apr 2009 Location: Token's life matters Posts: 1,836	4PK with 2s Lipo I have wanted more battery life in my 4pk. I have been running the Trinity pack with success. But I still wanted a lipo. But with me being so cheap, I wanted to try it before I had to spend any money. I had an old 2200 3s lipo (cycled it and charged it to 2700mah). I went rogue and cut it apart and removed 1 cell. Now I had a 2s lipo. I did not put ballance taps back, but I do plan on ordering another pre made lipo if I end up liking this. I went with a Castle BEC, because in the end anything that has to do with a crawler needs a BEC!!!! I set the BEC at 6.5 volts. It should stay at 6.5 until the battery gets low and once it drops below 6.5 I will know I have some time left before I damage the lipo but should think about getting it charged soon. The only draw back I am seeing is that I have to unhook the bec every time I am done to keep it from killing the lipo. I hope it has more life than a comparable standard pack, but that is yet to be seen. I am not sure its any lighter, but again I am hoping to get several hours of runtime. I am going to just leave it on the rest of the day to see how long it lasts. I will keep an eye out for a small switch to use inline with the battery to eliminate having to unhook the battery everytime I am done. The local radioshack had nothing small enough for me. EDIT: After reading 4xfords post I went buckwild and tore into my radio. I ran a wire up to the left side and added the smallest switch I could find. I switched the negative side of the BEC feed. I do not have to remove the battery cover to remove power from the BEC. I also took out the stock battery tray and there is a bunch of room now. I can fit a 5000 Hyperion in there, but that battery is the best one I have for my slash so for now I have lots of room with the 2200 I have. I will have to look for something in the 4000 range. This one was taken before I tightened the screws back up Last edited by The Violator; 09-19-2010 at 06:34 PM.

09-18-2010, 04:17 PM	#2
Sharkey Rock Crawler Join Date: Sep 2009 Location: Abbotsford BC Posts: 563	you can always rewire the radio to bypass the original switch, then run wires from the switch to between the battery and bec. that would give you a factory switch and not needing to unplug the battery.

09-18-2010, 05:23 PM	#4
treadway47025 Pebble Pounder Join Date: Dec 2005 Location: lawrenceburg Posts: 126	I dont understand why you need a bec in a radio controller unit.

09-18-2010, 06:00 PM	#6
Duuuuuuuude Suck it up! Join Date: Mar 2008 Location: Arkansas Posts: 11,652	I did the same with my React...works great. I hid the BEC in the handle so there would be one less thing to stuff into the compartment.

09-18-2010, 09:52 PM	#8
4xFord I wanna be Dave Join Date: Oct 2007 Location: Houston Posts: 3,761	Nice work Ted. I run a cc bec and a zippy 4400 mah 2s lipo. Just get used to unpluging everything at the end of the day. My radio is heavier than stock but that doesn't bother me at all. I love the ridiculous runtime it has. I ran 2.2 LCQ, 1.9, super, and 2.2 on the same charge. I leave mine at 7.1 volts so that I have a good buffer before running to low.

12-17-2010, 10:27 PM	#11
The Violator RCC Addict Join Date: Apr 2009 Location: Token's life matters Posts: 1,836	A little update. I took a 4000 4s lipo and split it up. I have been running the same battery since Late September. Many comps, many track nights with my Losi 8ight t and slash, and just ran the battery down tonight. About 3 months without having to mess with a battery. I would suggest to anyone looking for a longer runtime try this out.

12-17-2010, 10:48 PM	#12
Rootar Rock Crawler Join Date: Sep 2010 Location: Little Rock, AR Posts: 596	you know they make 2s Life packs just for the 4pk. no BEC, no mods, just plug and play ( you can even charge it with your dinky wall charger if your too lazy to hook it up to your real charger) here ya go http://www.allerc.com/hyperion-lifepo4-2080-mah-6-6v-transmitter-pack-p-4724.html

12-19-2010, 08:58 AM	#14
Scottmisfits Rock Crawler Join Date: Apr 2008 Location: Calgary Posts: 913	I have 2200mah LiFe from Trinity and I can get a litle over 30 hours out of it. I charge my radio batteries really low though. Instead of the 2.2a charge rate that they say is safe to use, I use a charge rate of 0.2amps. It takes quite a while to charge and it is a paint in the ass to charge on my charger because of the over capacity shutdown sfaety feature but it's worth it. I hate being at the track or the crawling course and having my radio go dead while I need to charge other batteries as well.

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