Colin, did you try out the 12.8mm rotor? what did you find out as for gearing and power etc.....?

Not really. Just the bearings are toast. If we know its going to rain we liberally cover our chassis and suspension with WD40 the mud and water just wicks off.

I have not ordered it yet....Christmas is getting in the way of my play time I will get one ordered up in the new year and will give it a good test.

Some testing info for you guys that like this kind of stuff. Josh Cyrul was in Thailand testing the ARC R10 touring car - and our motors and speedos. I will attach some links to see some runs.

The part I wanted to tell you guys about was that he was running a Black Edition VTX10R with a VST 4.5 motor in 95º temperatures - no fan on the esc. No Problems. Its all about getting the right set up to make the esc do everything it can to help you. Here are the video's from our Team ARC USA Facebook page:

https://www.facebook.com/photo.php?v=2674233631809
https://www.facebook.com/photo.php?v=2674252392278

WOW.... it's amazing the speeds that these guys are at compared to where we were 8-10 years ago running Touring.

What difference does the size of the rotor make? i.e. 12.3 v 12.5 v 12.8 but staying at the same number of turns.

Even though the BEC in the VTX10 is powerful enough would you guys still run a cap off the receiver like the one from spektrum. I figured it still might help smooth things out. Ill be running a s6040 servo with a airtronics 92744 receiver.

The LHS employee said he always runs the caps on the rec even with the viper.

General rule of thumb is bigger the rotor, more torque and less RPM. Opposite holds true too.

You shouldn't have to - its more dependent on your particular servo and receiver. I have seen people who can't run without one (with any esc) and I have never used one.

do you have his esc/motor setup sheet?

Any update on the 8th esc guys?

i like to know as i got to order few 1/8 stuff

And that's the best reason NOT to do it. I've yet to find a LHS employee who knew a turnbuckle for a doorknob.

http://viper-rc.com/vtx8.php

They are waiting on the delivery...you can order them through the Viper site.

The proper application for a receiver capacitor is to supply an extra amount of voltage / amp capacity to the receiver shall it need it. Think of a capacitor as a battery, a battery that can drain it's entire capacity almost instantly.

Now, the reason that one needs the extra capacity from the capacitor is that there is not enough amps at the receiver to supply the other electronics in the car. The capacitors first started showing up when everything started switching from brushed to brushless as the batteries at the time (NiMH) were much lower "C" rating vs today's Lipos and the ESCs were not very efficient with their BEC circuits. This led to the "brown out" conditions when using more power demanding equipment in the cars.

Once Lipos came allong, and a little refinement went into the receivers, a littler refinement went into the ESCs, and the need for receiver caps went away. For awhile.

There was a surge in the market a few years ago for ultra-high speed and ultra-high torque servos when Nitro 1/8 scale got huge all of the sudden. Allot of companies jumped into that business, and we had several new names in the game (like Savok, RadioPost, etc.....) All of which are good servos, but they are very power hungry.

The scenario NOW is that with the influx of these new servos in the market, is showing which radio manufacturers did their homework and who did not when it came to their receivers and the current they can handle. It is just that since it was not too long ago that the older generation ESCs and receivers would "brown out", people jump right back on to the bandwagon they are used to. They blame the BEC in the ESC.

Someone tries a capacitor and it works, but the finger is pointed at the ESC, when the fact of the matter is that it is the receiver that is a "bottleneck" in the system.

Honestly, I see this happen surrounding the same radio brand (Spektrum) when combined with Savox servos. It is my opinion that it is not the servos, as I have ran many different model Savox servos (currently have 1257 and 1258TG servos in my B4.1, T4.1 and an Associated 1015 in my SCTE), and have run the same setup in many different applications with ZERO problems. But I am running a Futaba 4pk with 603, 604, and 614 receivers.

Now I have loaned the same Savox servo to a friend at one point, who was running a Viper VTX10 ESC in his 2wd SCT. He started experiencing brown out issues (would get on the gas and loose steering or would cut out the throttle). Immediately he jumped on the ESC. I had to say "come on now, that servo works fine with my VTX10, so what else is there".

For the day he ran a Cap and it was fine, but that evening at the hotel, we swapped my spare receiver into the truck and he went and tested it the next day without the cap, and it was fine. Plugged in his Spektrum receiver (I think it was the telemetry Spektrum receiver) and the issue was there again.

I think the Spektrum product is just fine, I believe they offer a good product with a good value, but electronically they have a limitation, and if you need to run a hi-spec servo with a Spektrum brand system, you need to factor in you will more than likely need to run a receiver cap to make up for it.

Most people running Futaba, Airtronics, and Ko radios don't seem to have to run the capacitors on their receivers (unless they are running Spektrum transmitter modules with Spektrum receivers).

There could be an argument made that one really should look into the servo they are spec'ing and using, because to be quite honest, there is a point of lost return when it comes to speed on a servo. Very few drivers out there can actually take benefit of a servo that is any faster than about a .11 or .12 second transit time. I myself find myself turning my servo speed down on the savox 1257 or 1258 to help smooth the steering out.

That and if you have a .11 or 12 servo, AND would like more speed, remember, with a Viper ESC you can BOOST the BEC voltage to do just that. As long as your receiver can handle more than 4.8v, then by all means, crank it up. Run 5.5v, 6.0v, or even higher (most receivers now are spec'd for strait 2s lipo voltage for nitro applications)