AfterTithes

Hey all,

I bought the 17.5/10R package about two months ago. I have been running it in a 2wd SC10 in mostly blinky mode. Over the last two weeks I have noticed a significant loss of power. I keep the bell housing timing at 35* and have not recorded a temp over 170 after a 6 min heat/main.

(I have not changed any gearing either) I am used to keeping up/passing the Tekin and Trinity motors. Any assistance would be awesome.

Michael

dbracn

iTrader: (28)

Where can we find some setups? Coming from tekin, this seems to be a smoother esc but i only find support here. Didn't see any setups on the website. Progauge is easy to use but i was looking for common settings that most racers use. ex. th freq, brake freq, etc. I know there are many adjustments, just don't have the time to test them all. Ive been running blinky in sc but looking for some settings for a 8.5 in sc and 2wd buggy.

Thanks,

Dave

jordy-15

iTrader: (17)

hi all
need some help with brakes
where is a good starting point for setting up my brakes in 2wd buggy at the moment when i hit the brakes it want's to brake loose i thought it may have been a dodgy bearing that was causing the problem so changed all bearing through out the buggy and still brakes loose.
i have set them at
drag 15%
strength 80%
PWM 16000 hz
any advice would be very helpful
cheers

silvalis

iTrader: (29)

reduce your brake PWM

There was a setup a couple of pages back that had decent brake settings.
http://www.rctech.net/forum/10560860-post4362.html

jordy-15

iTrader: (17)

will try that
cheers

Glowster21

iTrader: (136)

Definitely something to play around with but reducing the PWM (Pulse Width Modulation) will make the brake stronger.
When you say break loose, do you mean when you hit the break your buggy wants to pull to one side?
If that's what's happening it could be a balance issue on the buggy, one wheel tighter than the other on the rear axle, diff may be off a touch....could be a couple things combined. Mess with the PWM first, I usually run mine around the 8000 range for 2wd buggy, but I also like to have a lot of brake "on hand" so to speak for those panic stops that seem inevitable at times.
I've had it happen before, where the buggy will want to almost spin when going full brake, and it's been as simple as double checking my rear wheel nuts to make sure I didn't crank one down too much when I was rushing to get the wheels on. Also happens at times when I'm still breaking in a new diff.

silvalis

iTrader: (29)

oh. mybad. thought it was the other way around.

Have you checked your diff? I'm running a RB5 SP2WC as well with a vtx10/spv3 8.5, using the Paul Sinclair setup with a few changes...

jordy-15

iTrader: (17)

yeah i checked that i put a B-fast diff in a couple of months ago and its still silky smooth and just tight enough not to slip. i have adjusted the PWM on both throttle and brake back to 4000 hz. ill see how i go next race meet with these settings
cheers

FLHX1550

iTrader: (11)

Some people have been able to run the lower KV rated 4-Pole motors on the VTX10R, but we do not recommend it.

We recommend that you ask the motor manufacturer what ESC they suggest to use. I believe that Tekin recommends the RX8, their 1/8th scale esc (not the 1/10th RS-Pro) for their 4-Pole motors.

The VTX10R is designed for 1/10th applications, and the 540 4-Pole motor design is basically a "shortened" 1/8th scale motor.

FLHX1550

iTrader: (11)

More than likely the magnet has been heat-soaked several times and it has weakened the magnet.

Though temps in the 170 range are not hot enough to melt anything internally, it is hot enough to damage the magnet if done multiple times. This is the nature of all motors, not just the Viper motors.

You have to remember that temping the outside of the motor tells you exactly that, the temp of the outside of the motor. It is a good point of reference, but not a real accurate way to tell what is going on inside the motor. There can be up to a 60-80 deg temp difference between the outside of the motor and the inside.

The biggest killer of stock motors, IMO, is practice. Going out for 10,12 or even 15 minutes and holding the motor in those temps just kills the magnet. At the Chi-Town shootout, the top 4 or 5 guys in 17.5 buggy were blistering fast (they would be in the top 5 in 2wd Mod) and were running the temps in the 170-180 range after their runs, but would change the rotors every 2 runs.

FLHX1550

iTrader: (11)

go to www.viper-rc.com and log-in to the forums. There are several areas dedicated to setups.

idrummerboy13

iTrader: (15)

throw the pwm down to 5000-6400
-2 exp
drag-25%
The brakes on these speedos are really good, Mine is at 40% on my radio, 67% on the speedo and I have plenty. You want enough brake so you can work with it, let it stop you but don't let it brake you loose, play with it. Good thing u have a sick programming card with these

FLHX1550

iTrader: (11)

I believe he is talking about the Drive PWM Setting, which in certain applications like 550 motors or very low turn 540 motors, of using 12,000+ for the Drive PWM Freq

jordy-15

iTrader: (17)

sorry guys i should of added that i am running a stock motor 17.5 also when i say brake loose i mean spins out.
i only started having this problem when i swapped out the motor and upgraded the diff.
so if i try more drag brake -expo and decrease travel on the transmitter it should fix it ??
cheers

Glowster21

iTrader: (136)

As much as you're not going to want to hear this, it's more than likely diff related. May be too loose and when you brake the diff is overcompensating on one side and spinning. Happens to me during my break in period all the time. Tighten the diff in very small increments and you'll find the balance you're looking for. Do keep playing with the PWM for the brakes though until you find your "happy place". The brakes on the Viper ESC's are very strong and adjustable as you know. I usually get guys asking how the brakes are on these, I tell them but they're still a little unsure. Then I pull out my 4wd buggy, drop the PWM on the brakes, do a drag type run down the straight pegging full break at the end of the straight. When the Buggy pulls an immediate endo on its front wheels and comes to a dead stop, the guys lose all doubt.