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Old 01-14-2005, 04:45 PM   #91
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I think some of you are missing the boat regarding drive frequency and acceleration. For example, V7.1 vs SR. They do have similar specs and the same drive frequency (3140hz), but you guys are overlooking the minimum drive factor. That is an adjustment that is used to give more or less punch at the hit of the throttle. Maybe LRP designed the SR to have more minimum drive to give it a stronger feel with weaker motors. I know LRPs V6, V7.1, SR, etc. have an adjustable throttle curve, but I think it's only used with the current limiter. If the plugs are removed then 100% of power output is available, but the minimum drive isn't changed. It must be programmed into the software of that line of speedos. That's why I like my Cyclone so much. Even though it requires a programming device it's really amazing how many things can be adjusted if need be. You may never use all of the settings, but they're available if you want them.
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Old 05-08-2012, 03:45 AM   #92
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Sorry reviving this thread.

Im just curious about drive frequencies of today's brushless systems.

I have a GTB2 X-Drive that has adjustable drive frequency.
It says, increasing the drive frequency makes it smoother:
Settings are in 1 to 10 but the Drive Freq started at 16khz and descended to 7khz
So if I set it to 10, the drive freq is at the lowest (7khz)?

Whats the effect in batt consumption and motor heat if I use a high freq or the low freq? Does a lower drive freq (7khz) yields more punch and acceleration?

For the experts, please elaborate.
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Old 05-08-2012, 09:57 AM   #93
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I have my gtb2 with Xdrive at 7khz with 15% minimum drive, and it really makes a huge difference when I run my radio throttle expo up to 30% and fwd acceleration at 40%... That's with a ballistic 17.5t motor at 3.65fdr and N timing... Nobody runs me down the straight when I accelerate at the same time... If novak had expanded their throttle profiles to include a convex profile also, it would be unbeatable....
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Old 05-08-2012, 04:14 PM   #94
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Quote:
Originally Posted by bertrandsv87 View Post
... If novak had expanded their throttle profiles to include a convex profile also, it would be unbeatable....
I think this was done for the off road guys, but I totally agree with you, its linear or nothing at this time.

What transmitter do you use, as I'm not familiar with "fwd acceleration" setting?

Thanks
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Old 05-08-2012, 06:38 PM   #95
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I tried 7khz last night and didnt notice any difference. Will try it on the track if I find the time. Right now Im at number 5 profile. BTW, Im using 13.5 Ballistic on a FF03 kit.
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Old 05-08-2012, 06:59 PM   #96
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Quote:
Originally Posted by Airflow View Post
I tried 7khz last night and didnt notice any difference. Will try it on the track if I find the time. Right now Im at number 5 profile. BTW, Im using 13.5 Ballistic on a FF03 kit.
The freq, between high and low, is the spread of the steps on the acceleration curve. Low freq is coarser or more stepped and high freq 16khz is smoother on a curve. I tend to run high freq as it also runs a little cooler for me mostly on the speed control, but the expo curve on the acceleration will definitely get you the punch out of the corners. I will run anywhere from 20 to 50, and have tried 75, but that didn't feel smooth to drive.
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Old 05-08-2012, 07:07 PM   #97
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"20 to 50, and have tried 75"

Huh? Where can I try these drive freqs?

GTB2 has these range only: 16, 15.2, 13.8, 13, 12, 11, 10, 9.5, 8, 7khz
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Old 05-08-2012, 07:47 PM   #98
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I have a futaba 3pm fm radio, and I think their fwd acceleration is the same as throttle speed in other radios. Also, as far as I understand, the lower drive frequency(7khz) makes the speedo run cooler, but is harder on the motor; higher drive frequency is harder on the speedo, but easier on motors...
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Old 05-08-2012, 07:50 PM   #99
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Airflow, I think he means 20% to 50% throttle expo on the radio, not the speedo....
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Old 05-08-2012, 07:55 PM   #100
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I also run a shaft drive tc4 with a front spool, and the punch out of turns is a smudge faster than belt driven cars, when you combine that to all of the above....
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Old 05-08-2012, 08:03 PM   #101
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Ah ok. I really dont use expo for throttle. Even at 16khz on the track, my esc ran cool and thats 20mins of continuous running, motor is hot to the touch though. On 7khz last night, I noticed slightly cooler motor and didnt feel decreased smoothness.
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Old 05-08-2012, 08:06 PM   #102
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So you're saying is if I want punchiness, I should leave it to 7khz? How bout run time? Will it still be the same regardless of which drive freq I choose?
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