Check all the basics - make sure all wires are soldered properly. Make sure sensor wire is fully put in both motor and speed control. Unless something happen at the very end of your last run - just changing motors should not cause any power issues - or the need to re-calibrate anything.

is it norman for a 17.5 to cook after only 2 race days? Only ran at 80c? got my rma# just got to find the cash to send it back to cali.

nitro - 80º C = 176º F (sorry had to do the conversion for myself). Yes, if that is what you are reading on the outside its pushing it with temperature. Especially if run to that temperature multiple times over a two day period. We recommend to keep the temperatures below 160ºF (71ºC) for best performance. I actually like to stay around 150 unless "pushing it for a big race". Sometimes you get a little more speed if you push the temperature, but the trade off if pushing how long the motor could last.

only running 5min races with about 1hr inbetween qual's. didnt think 9deg would make such a major difference. know for next time i guess. oh, those 2 race days where 2 weeks apart.

its not really the 9º on the outside to worry about, its the higher internal temps. If it over heats too much one time, it can hurt it. Heat is the enemy with all these electronics.

I ran my B44.1 this past weekend with a VTX10R and 6.5T motor. It ran great for three or four minutes then it started cutting out. I thought it was the battery but when I put it on the charger it showed 7.8 volts. The ESC and motor were still cool to ther touch. It wasn't thermalling. I am at a loss on what this could be. Could it be the senso wire? Any help would be great.

Need some clarity!!! I need a 1/8 ESC and Motor for my Associated RC8Be ASAP. So I can get in some test races before my big race in sept!!! ????? So what's the verdict ?????

Definitely suspect the sensor wire. I just learned how finicky they can be. Had 3 I thought were good only to find out they weren't when I hooked them up to the viper. If you have another sensor wire you know is good try it to eliminate the problem. I'm new to vipers so unless viper has a history of this type of problem then the sensor wire is the first thing I'd suspect.

Thanks Mulepic, I will change it tonight and see if it helps.

jrj - sensor wires are finicky things with any esc - all those little wires and connections - its easy to pinch one and not see it, especially in a 4wd where wiring can be tough.

Also check your motor and esc temp cut offs - if set to low, they can shut the system down (like they are supposed to) if you hit those temps. And remember they measure internal temps, not outside temps. But sensor wire is a pretty common troublemaker as well.

spider - our 1/8 systems are still in he testing phase. We have no public time table on release. Our goal is always to make sure our customers get quality products, we would rather hold it back and make sure its right, then release with issues. There are only a few test units in the country with a select group of test drivers. That being said, I like what I see so far!!

are the new 1/8th units coming with presoldered wires as well?

can the vtx10r run sensorless ? i tried calling tech support like 3-5 times today through out the whole day and got voice mail

That's what it does best.

OK Re-Binded my vehcile! Checked all the solder points! Battery is charged and good! Go to re-calibrate Full pull on trigger and lights blink with tone. Go full Reverse. Then Nuetral! Before I get any futher the truck turns on FULL FORWARD without even touching the trigger! Will not turn off!!! Have to pull trigger full pull to get it to stop then can turn it off! If I go full reverse it goes forward @ lightning speed! HELP HELP HELP!!! Sensor wires are all in place right also! Ugh... Does anyone know what is wrong???

People @ my 2 local tracks are telling me to dump them. I just bought my 2WD System a month ago. I love my 4WD Copperhead with 5150KV!!! But this VTX10 with 8.5 or 17.5 has been nothing but a hassle.