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Old 05-03-2009, 09:37 PM   #241
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Anyone running an spx with single cell lipo 17.5 12th? Findings?
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Old 05-03-2009, 09:38 PM   #242
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Did you guys notice a difference in infield punch when geared 4.8 vs. when geared 5.4? My last run at NorCal I was geared 5.6 with profile 8.
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Old 05-03-2009, 11:16 PM   #243
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Did you guys notice a difference in donkey punches when geared 4.8 vs. when geared 5.4? My last run at NorCal I was geared 5.6 with profile 8.
You do some weird testing, bro...

Seriously though, I think gearing substantially lower than 5.6 is the way to go on that track.
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Old 05-03-2009, 11:22 PM   #244
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Old 05-03-2009, 11:25 PM   #245
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What he failed to mention is the 10degrees of timing he added on the motor.
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You do some weird testing, bro...

Seriously though, I think gearing substantially lower than 5.6 is the way to go on that track.
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Old 05-03-2009, 11:25 PM   #246
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Can anyone recomend gearing for my TC5 with a 13.5 with an SPX on power mode 8?

Thanks in advance
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Old 05-03-2009, 11:34 PM   #247
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Can anyone recomend gearing for my TC5 with a 13.5 with an SPX on power mode 8?

Thanks in advance
Depends on what motor you're running and how much timing you're using.
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Old 05-04-2009, 03:20 AM   #248
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Sorry wasn't too specific on that. It's a novak 13.5 with a 13mm rotor never changed the timing on the motor itself.
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Old 05-04-2009, 07:05 AM   #249
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Some comparative dyno runs.

LRP SPX Stock Spec ESC
LRP X11 10.5t (ceramic bearings, extra cooling front plate)
SMC 5000mAh 28c

The current curves are very interesting (keep in mind the current reading on the Sentry is clamping above ~110A). You can clearly see the punch levels, the profile 1,2,3,4 increase in punch and it looks like (1,2,3) & (4,5,6) & (7,8) have similar timing profiles. You can also see the new Stock Spec profiles 5,6,7,8 increasing in punch, with 5,6 having a similar timing profile as profile 4 and profile 7&8 having large amounts of timing past the power peak. Any wonder you need to be careful on 7&8 with the motor pulling 30A at almost no load.

You can hopefully see why gearing down is good thing on profile 7 & 8.
Attached Thumbnails
lrp spx stock spec-lrp_spx_x11_10.5t_all.jpg   lrp spx stock spec-lrp_spx_x11_10.5t_p5678.jpg   lrp spx stock spec-lrp_spx_x11_10.5t_allcurrent.jpg  
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Old 05-04-2009, 08:21 AM   #250
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Originally Posted by gameover View Post
Some comparative dyno runs.

LRP SPX Stock Spec ESC
LRP X11 10.5t (ceramic bearings, extra cooling front plate)
SMC 5000mAh 28c

The current curves are very interesting (keep in mind the current reading on the Sentry is clamping above ~110A). You can clearly see the punch levels, the profile 1,2,3,4 increase in punch and it looks like (1,2,3) & (4,5,6) & (7,8) have similar timing profiles. You can also see the new Stock Spec profiles 5,6,7,8 increasing in punch, with 5,6 having a similar timing profile as profile 4 and profile 7&8 having large amounts of timing past the power peak. Any wonder you need to be careful on 7&8 with the motor pulling 30A at almost no load.

You can hopefully see why gearing down is good thing on profile 7 & 8.
Gameover

Now that is some good testing! Thank you.
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Old 05-04-2009, 08:48 AM   #251
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Old 05-04-2009, 01:16 PM   #252
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can someone please explain the graphs a little more??
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Old 05-04-2009, 02:40 PM   #253
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Quote:
Originally Posted by gameover View Post
Some comparative dyno runs.

LRP SPX Stock Spec ESC
LRP X11 10.5t (ceramic bearings, extra cooling front plate)
SMC 5000mAh 28c

The current curves are very interesting (keep in mind the current reading on the Sentry is clamping above ~110A). You can clearly see the punch levels, the profile 1,2,3,4 increase in punch and it looks like (1,2,3) & (4,5,6) & (7,8) have similar timing profiles. You can also see the new Stock Spec profiles 5,6,7,8 increasing in punch, with 5,6 having a similar timing profile as profile 4 and profile 7&8 having large amounts of timing past the power peak. Any wonder you need to be careful on 7&8 with the motor pulling 30A at almost no load.

You can hopefully see why gearing down is good thing on profile 7 & 8.
The cat's out of the bag!! Bearing in mind that power = torque x revs, you can now see why it is so important to gear down. 7 and 8 give you much more revs, but there's no torque. To get more power, you have to gear down so the motor can access the increased revs, otherwise it will be slower, and consume large amounts of energy to generate heat.

Well done gameover - the game's over now!!
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Old 05-04-2009, 03:39 PM   #254
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so from what i make out from that graph is profile 6 would be a much safer
profile...i havnt run my spx yet on track but is there much in it between say profile 6-8

or is profile 8 the one to be on but just gear down 3 teeth?

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Old 05-04-2009, 03:51 PM   #255
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Quote:
Originally Posted by SlowerOne View Post
... 7 and 8 give you much more revs, but there's no torque. To get more power, you have to gear down so the motor can access the increased revs....
"no torque" - I don't think so. From about 0 - 12K RPM, profile 2-8 all have the same power. Therefore for any given RPM, they all output the same torque. Profiles 7, and 8 further extend this by giving MORE torque at any RPM higher than approx 12K.
I think the reason for gearing down is to not overheat the motor.

Well done GameOver. I salute you.
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