First, I want to clarify the fan information - thanks to nate79 for making me look into it, I haven't run a fan on my 1/10 stuff for 4 years.

I spoke with our engineers and this is what is happening/changed. First, our units were actually designed not be used with fans, and the high majority of the time they are not needed. As we have developed the product and software over the last 5 years we found that operating the fan via the port on the circuit board could take a small amount of performance from the system. So with the new a64 software and the current version of the units, a fan port was mounted on the capacitor board - so its powered directly from the battery. And the a64 firmware disables the lower fan connection, to make all the possible performance available to the system.

If you have an older unit that does not have the new capacitor board fan mount, you can wire the fan directly to the + and - of the battery, to get the same result.

Feel free to PM me with any other questions.

VF4 questions:

boborc and Cain - the VF4 is a 540 can size.

Cain - can design -- well actually the VF4 design was very much influenced by how successful our vx4 sensorless motor operated. Over the time we have had those motors in service they have performed very well with few number of issues. So that became the launch point of the sensored version. With some other improvements as we went along. Finally, the matte black finish is in line with what we have tested with 540 2 pole motors and been very happy with the finish and how it lasts over months of operation. There is a train of thought that ribs can provide some additional surface area to cool the motor, but testing showed the can would work within the parameters we expected.

See, this is why I race 1/8th scale. I was totally wrong. Sorry guys.

I am having problems with my VF8 1900. It was running strong, I shut it down and let it cool. After it was cool I plugged a fresh pack in it and ran it but it was way down on power. I took expo out of the radio, increased punch from 50 to 85 and total power from 85 to 100. I am running it in a mbx7e, 15/46 pinion/spur, vtx8 esc. I took the motor apart took to inspect it now it doesn't work at all. Also when it was running down on power it got hot really fast.

Its under-geared. Im at 16-17 on my mbx7 Eco with the same motor and VXT8 speedo. Also make sure there is no, NO boost in the motor

Plus it could have a shot bearing

how deep are the motor mount holes on the 1/10 motors and is there some sort of "protection" from threading a screw in too deep? I know some motors have a ring that stops you from doing that, and some don't.

My Dex210 was bought as a used roller. It came with a spare chassis and body. The spare chassis was the longer, plastic version that I thought would be better for my track. I take it out and look at it, the spare body for that chassis is covered head to toe in every Viper sticker known to man. This motor was meant to be.

What were the temperatures you recorded? Also describe "took the motor apart" - did you disassemble it? Does it show any sign of running? Too hard to tell - could be sensor, wiring? PM me with more details.

The 1/10 motors do not, if you put a screw in that is too long it could possibly go all the way to the insulator ring. The VF8 does have a shroud cover, but that is because the wiring on the 4 pole is different. I want to say the longest screw I remember measuring was 8mm, but don't hold me to it. Plus it depends on how thick your motor plate or mount is.

Help please! I am fairly new to the rc scene and this is my first summer racing.

First I have a b44.2 that I ran all winter with a vtx10 esc and a sonic 7.5 mach2, the gearing was at 23/81 and neither the esc or the motor ever ran too hot. The esc stayed under 120* and the motor stayed under 140*. I race in Az and the temps have gone up causing me all sorts of havoc and heat. My esc now comes off at 160* and the motor stays about the same as the esc. I have now twice changed my pinion going first to a 21t and now a 18t but haven't had any luck getting the temps down. I was told to put some timing into the esc would help but I have been hesitant, up till now I haven't used any timing with this buggy. Can anyone please give me some advise as to what I can do differently to cool this thing down. If it's gearing what gears? If its timing how much, what start/finish rpm, and slew?

Next I purchased a rc8.2e. It came with tekin motor/esc setup but I run all viper so I changed it out to the vtx8 and vf8 2700. I have the same question as before. Recommendations for gearing/esc setup. Should I run timing or not?

Thanks in advance for your help.

You got the 2700 to go in your rc8.2e with the VTX8? Are you racing this?

The 1900 or 2100 would have been the better choice. You can always use the Tekin motor it came with along with the VTX8. What model is the Tekin motor?

Thanks for the info!

well, going to try typing this again as chrome crashed on me.

Got some questions from my race yesterday. All speed controls mentioned were upgraded to a64 version.

For 1/10 scale, the viper VTX10R-BE worked excellent in my 1/10 2wd buggy using the 10.5 motor unboosted. I just adjusted gearing, probably the only thing I would have a question on would be the following:

- starting recommendation for boost settings
- any gearing recommendation to target
- improvement of brake power

For the Viper VTX8, I ran it in two classes, 1/8 E buggy and 1/0 4x4 SCT.

In E-buggy combined with the 1900Kv motor, no issues in general to report. The only thing I really noticed different was that punch settings seem to be softer than same setting previously.

For 1/10 4wd SCT, I ran the following:

- VTX8 with a64 software
- IP 7200mah lipos
- Hobbywing 3656SD 4000kv
- Futaba S-FHSS receiver
- Hitec 7955TG

Main setting changes from the 4wd sct profile were:

- Cutoff voltage 6.8V
- Motor temp protection 240 degrees
- 60% punch control

1st qualifier which I believe ran for 6 minutes, I had an issue towards the end of the race where I lost power. I had steering, just no throttle response, it just seemed to go away. Unfortunately my vehicle was shutoff before I could get to it so I couldn't see any lights, etc. I thought maybe it was the same voltage cutoff issue I had in the past with the previous version, so I dropped voltage cutoff to 6.4V, I also dropped the pinion size however the motor and ESC temps were not unreasonable for the class.

Second qualifier, same issue happened again. This time I managed to get a brief look at the lights before I bumped the power switch from habbit. it seemed like 2 lights spaced 1 apart blinked briefly. I am thinking this had to do with motor temp issue, however temping the motor, it was a fine temp. confused, I recalled that the stock temp cutoffs were disabled, so I went ahead and turned it off, and went down in pinion size again.

Ran 3rd quali and 8 minute main, and no more issues with it wanted to temp cutoff or voltage cutoff.

So in short, did something change in the a64 profile that could be causing what i am seeing as these same settings for temp control I had no issues with on the previous version?

All in all though, Viper ESCs worked great. heck the loaner vehicle I sent out for someone to use (1/10 2wd buggy) the borrower equipped it with a Viper 7.5 and kicked butt with it. was hilarious lol.

got the copperhead vx4.39 combo and having issues. when i first got it i checked to make sure it worked (plugged it in and gave a small tap of throttle. thats it.) then it sat while i built my kit. by the time i was ready to use it i get just a lot of cogging and little to no movement. never ran the system for more than 5sec durng initial check. cogs even when not in my car. tried hooking up the motor to another esc and it worked fine (motor beeps and runs good). it also gets pretty hot just being on (about 100F). can anyone help before i send it back for warranty?

Cain - wow, a lot going on there. Might be better to handle through PM. Send me your current brake settings - so I can see to make a recommendation.

Couple other quick notes. If your voltage cut off was at 6.8, that's already high, then the VTX8 actually starts to activate the cut off a few tenths earlier. So with a 4 pole motor and all that current draw - it was probably touching the battery cut off. I have seen data showing a battery can drop 1 full volt with some amp spikes from a 4 pole motor.

Also with temps - cut off was at 240 - but what did you measure? If it was up towards 160 might have hit the cut off from the internal readings on the sensor plus any variance in the sensor - there is always a variance between mfg's. More via PM.

awpldlto- sounds like you already did the biggest thing. If the motor was running on a different esc with no issue, its was either the first esc or a bad connection. If you put the motor back on the esc does it still happen? If it does, then would send it back.

Thanks for the reply,

It came with the 1900kv tekin. It isn't bad but to keep up it would be nice to have the extra power. The other reason was to not have to push it as hard as I do now. The gearing in this is 18/44 and it thermals on the motor. I have the cutoff at 220*. To get it not to temp I changed the throttle EPA in my mt4 to 85% but now it really has issues keeping up with the nitros. I was also kicking around a Orion 2500kv. I know it's a lot of motor but I am pretty set on stepping up. Any thoughts on gearing for either motor?

Also curious if you or anyone else has any ideas on my b44.2.