If he can touch the esc and hold fingeron that and motor. It can't be but so
hot. I would go with internal bec as well. I had a simaliar problem with a bk.
Unless he has a bending issue. Then that causes problems.

Quick Question - i will be running quark125B and two orion lipos will i need a separate small batt. pack for the reciever and or servo like those triangle or octogon packs like by venom. Or will the lipos be enough to power the motor, esc, reciever, and 333 oz torque servo. And if i do need to use one of these were do i plug it into the seervo or do i use a y conector or something thanks.

You can run a 4 or 5 cell receiver pack for the servo(s) and receiver, but it just adds to the weight and it's just one more thing to charge. Far better is to use a UBEC to bring the main battery pack voltage down to 5 or 6 volts. This lets you use just one set of batteries - your main ones. The power needed to power the receiver and servo(s) is minimal compared to the brushless motor requirements so any difference in runtime will be neglible.

You CANNOT simply use a Y adaptor to directly power the receiver as the voltage would be too high. Even 2s would be too much. You do need a receiver battery pack or a UBEC (but as I said, the UBEC is a better choice IMO).

The ESC has a BEC built-in, but if you are running anything over 3s, you should definitely use an external one. The built-in one is a linear regulator and will heat up.

I think that the drilled pinion might be causing some of your problems. The gears are cut on precision machines so that the hole is PERFECTLY concentric (in the middle). If you think about how fast 50,000 RPM is you can see that the slightest imperfection can cause big problems. Thats how vibrators work. Its just a weight with the whole drilled offcenter. Just for the record im talking about vibrators in cell phones!:005:

No, if this was the case it would had caused binding, which would have lead into overheating. like he says; it's not that hot.

well its a week till our nationals here and ill be joining the ep mt. I wrong about my gearing it a 66tspur/18tpinion. my tires are 40 series bowties on wabash with 23mm hex. Have a question how do u turn of the bec on a MM? will try to tune my truck this week for the big race. ill update u guys during the week if it works out already

To disable the BEC, just remove the red wire from the throttle plug. Either that or use a small servo extension with the red wire totally removed.

so by disabling the bec u think it will solve the problem of my esc shutting down ?

Yes, possitive. You need an external batteriepack/ubec however.

hey thanks guys! u guys are always a big help! thank you! will update you guys as soon as i get things working.

the external battery pack will be connected to the reciever?

Yes, in the battery slot. Be sure to get the middle wire out of the esc plug

so all in all i would be just fine running 2 lipos and i would not need any other source of power than the two lipos to run my reiever and settering servo right.

ok ive locktight my grub screw already and im leaving it over night to dry up. Now by tom. ill be getting a ubec from our local hobby shop. does the ubec brand matter? i've put a fan on top of the mm just to cool it down but my problem is that when i connected the plug to my reciever's batt it didnt want to work? i've tried connecting it staight to the battery and it works. do u think its my reciever that's the problem throttle and steering seems to be ok. Also, ive requested from brianG a diagram on how to connect the ubec in the system. Is there another way on getting the fan going? Thanks for the support! hopefully my mt will be up and running with no problems for the nationals this weekend. Thanks again!!!

You can hardwire the fans... to the esc's main power leads from the battery if the fans are 12v, or to the output leads from the ubec that go to the rx if the fans are 5v.

The ubec is easy to wire up... it will have two input wires that go to the battery and two output wires that go to power the rx. You will have to hardwire or make a connector to hook up the input leads. And you might even have to put a rx connector plug on it to plug into the rx...