FXR shuts down everything ... odd problem

[axlesofevil]

hey guys im trying to figure out my new FXR setup and am running into a strange problem.

here is the setup.

axial based crawler
FXR and Tekin 35t
CC 10amp BEC
Geared 13/87
Hitec 7955TG
7.4 lipo
about 2lb total weight each front wheel including wheel/tire
a little under 1lb total weight rear
stock diff gears. stock trans

when i "roll" onto the throttle everything works fine.

if i mash it from a stop the whole truck shuts down, even the servo and reciever (even when running the BEC...)

the truck will also shut down if it gets a little bit (and i mean even a little bit) jammed up and gets some load on it...

litterally the whole truck shuts off.

after it shuts off, to get it started i have to unplug the battery and plug it back in, the FXR isnt flashing any heat problems or anything, it just shuts off completely, i cant figure it out.

any good ideas?

ive had it sitting next to me turned on for about 5 minutes now and nothing is warm, no problems at all... i really cant figure it out

[chevellian]

I would first try a different battery just to make sure. If you get the same results, It is possibly a bad connection somewhere, cold joint,broken wire etc.

[AreCee]

WOW!! Two pounds in each front wheel!!!!!

[Meatwad]

Lol thought mine felt heavy at 7oz per front and 3oz per rear

[Flyin Hawaiian]

drop the weight in your front wheels to about a 1lb a piece. i think your rig is too heavy. that why it overheats the esc. You dont need that much weight to crawl. if thats what it takes for your crawler to crawl. than your rig setup is wrong.

[clockworks]

It does sound like you are drawing too much current from the battery - the voltage drops, shutting down the ESC and/or Rx.

When you give it full throttle from a standstill, you pull more current than if you gradually accelerate to full throttle. The high weight makes the problem worse.

Try a bigger battery (higher mAH rating).
What are the specs on your battery?

[axlesofevil]

guys the wheel weight includes the wheel and tire complete. im not sure on the exact weight added, but its about 2 wraps of stick on weight up front and 1 wrap in the rear, its really not much weight at all compared to other trucks ive seen.

Clockwork i'll try that and see what happens.

the battery in there now is a losi 7.4 2000mah 20c lipo

[Culetto]

Double check to see if your lipo cutoff is too high. If you mash the throttle it will draw down on the batter for a shift period of time. If this draws the battery lower than the cutoff voltage it will disable the esc and shut down.

You could also try wiring your BEC to power the reciever and remove the red wire from your esc plug. If the servo still moves and the esc is shutoff you have narrowed the problem down to that point.

[JohnRobHolmes]

Yeah, my guess is that the battery voltage is dropping when you pin it.

[axlesofevil]

well you guys were totally on the money, i stuck one of my 2s car packs in there 5000 mah 20c and the problem was gone.

so the question now is, what do i do for a battery, do i need more MAH or more C or what?

ideally i'll be running a 3s lipo in it soon

any ideas? im using the front axle battery mount so i need a max width of 73mm on it and im having a hard time finding anything in that small size with anything over 2000mah.


edit. well i found even more clarity into the problem. i was using http://www.losi.com/Products/Feature...rodId=LOSB9820 as my battery in it. which i was using in an MRC with no problems, but i guess bc its only probably a 10c pack, it cant handle the draw?

[Ktbone]

Try one of these: http://www.valuehobby.com/product_de...d=8&item_id=65

I've had great luck with mine and get 30-40 min of crawling depending on how much full throttle time I spend on it.

[Culetto]

Originally Posted by axlesofevil

well you guys were totally on the money, i stuck one of my 2s car packs in there 5000 mah 20c and the problem was gone.

so the question now is, what do i do for a battery, do i need more MAH or more C or what?

ideally i'll be running a 3s lipo in it soon

any ideas? im using the front axle battery mount so i need a max width of 73mm on it and im having a hard time finding anything in that small size with anything over 2000mah.


edit. well i found even more clarity into the problem. i was using http://www.losi.com/Products/Feature...rodId=LOSB9820 as my battery in it. which i was using in an MRC with no problems, but i guess bc its only probably a 10c pack, it cant handle the draw?

Sounds like you hit the nail on the head. There are a number of inexpensive alternatives to brand name LiPo's. Check out ebay. I pickets up 3 11.1v 1300mah 25c Tenergy packs recently for only $50 bucks including shipping. They are small enough to front axle on my axial based rock racer.