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Old 09-06-2010, 11:46 AM
  #1846  
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A.S software, first page, bottom right box. add. timing only at full throttle
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Old 09-06-2010, 12:00 PM
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Originally Posted by YZFAndy
At housey
I was running at 7.5 and Martin gave me this advice. It seemed a bit too much of a step at first to jump from one ratio to another so i just kept doing five minute sessions and adding one tooth at a time. The result at first wasn't anything but then the motor started getting more punch, faster and cooler. The other thing i notice was my batteries were needing 2500mha to charge them rather than before only needing 1800mha, so energy is going somewhere.

I'm now running at 5.8 but i'm still messing with the timing and higher gearing because its only just starting to get warmer now at 60degress c and still seems to be gaining top end punch. I guess the only thing that will limit performance or what i'm looking for is for the motor to just be off heat fade at the end of a race! Would that be right?
As I have only just started racing again after some years away all this brushless stuff is very new to me, so like you say it feels like a massive jump to make. The main issue in my mind is moving away from how I used to think when gearing a brushed motor. The concept of gearing a lower fdr and it getting cooler and faster is something a bit new and scary to me .

But if you can't trust these guys who can you trust? So next meeting I'm going to dive right in there. Barriers beware!
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Old 09-06-2010, 01:23 PM
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Where can buy a gm motor in the usa?
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Old 09-06-2010, 03:48 PM
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The next track I'll be at is a little smaller/tighter guys,



I was thinking around 7fdr, or is that still too high?

Would I be right in saying that the GM's are geared with a much lower FDR than other brands. People running other brands seem to have smaller pinions and let the system rev. Is that because the GM system as a combination has more torque?

Last edited by housey; 09-06-2010 at 04:55 PM.
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Old 09-07-2010, 01:21 AM
  #1850  
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if this is smaller than the ardent racing track you should be running 5.8 there and 5.5 at ardent (approx)


yzf: the telemetry only shows the correct value when you push the button shortly after you raced (that means the speedo saves the actual temperature)
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Old 09-07-2010, 01:27 AM
  #1851  
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Default GM made easy V13.0

GM made easy – V13.0

Since I wrote the last tutorial quite a while back I feel like with V13.0 it is a little outdated.
So here is a new one.


Download V13.0: http://www.gm-racing.de/rwdownload/index.php?dl=154
This Tutorial bases on the file: V13_basic.gd2
I MESSED up the Transmitter data so please note that if you copy this file onto your speedo you NEED to redo your transmitter setup (-> pick the mode via transmitter).
When properly done, the full throttle value should be something around 1.9ms, neutral between 1.4-1.5ms and the full brake value should be around 1.1ms.

With this file there are only 4 values that you change according to the motor / class you race and the track you race on.

1, Amp Limit

For any kind of Stock Racing (13.5/17.5 or slower) 80A is by all means enough. Most drivers actually prefer even less. In regular racing you actually not really reach that value anyway and in the cases you do reach that anything above 80A only creates heat instead of power.

For 10.5/6.5 the Amplimit should be 130 – 150A
For Modified (5.5 / 4.5) 140-180A is the desired range

2, Switchpoint RPM

When racing Stock I usually prefer not to use a switchpoint (Reserved 4=1). But this requires really smooth throttle control sometimes so in the sample file I enabled the switchpoint (Reserved 4=3) and set it to 10000 RPM. Anything Less is pretty much pointless.

Note: The LRP X12 requires a switchpoint to start properly! (different sensor position)

For 10.5/6.5 the switchpoint should be between 15 – 25000

For Modified 5.5T 25000
4.5T 35000

3, Fixed Timing / Max Timing

Fixed Timing handles the power! The value for both Fixed and Max Timing can only vary between 0 and 30! Max Timing values above 30 will disable the Max Timing feature!
Max Timing is only use when the launch control has been activated ( no throttle input for atleast 5 seconds). So you can have that extra bit for the start.
I always set Max Timing to Fixed Timing +1 as a general rule.

I know that people tend to overdo it with the timing values so here is what should be the highest values:

Graupner / Corally 13.5: 25
GM 13.5T: 24
LRP X11 13.5: 29
LRP X12 13.5: 20!!!
Speedpassion 13.5: 25

Modified (GM) 5.5T: 15
Modified (GM) 4.5T: 12

4, Motor Cutoff Temperature

The Tempcheck Feature only works with GM, Graupner, Novak, LRP X12 and Corally Motors.
Speedpasson and LRP X11 do not feature a Temperature Sensor so be carefull not to blow those up.

Values for various motors:

GM motors: 115°C
Graupner / Corally motors: 125°C
Novak: 115°C
LRP X12: 120°C

That’s it.

What if:

-The Motor gets too hot: gear harder / use less fixed timing
-The Motor is running cool but there’s not enough power: gear harder / use
more fixed timing
-The Motor feels slughish but temps and power are ok: you are overgeared
(although you really need to gear superhard to reach that point! (indoors
around 4.2 with 13.5T)
-Not enough brakes with LRP X11: update to V13.0 and set Reserved 4 (in
the telemetry tab) to 5 (if you used 1 ‘no switchpoint’ before) and 7 (if you
used 3 ‘HST with switchpoint’)
But with the basic file posted, there should be enough brakes as this has
been set already.
-Sudden loss of power: clean the motor and especially the sensors, check
the senor wire and the magnet

Basic Tips:

-A fan is always better as it enables you to run more timing
-Always make sure your motor is really clean

LRP X11:

-Set the Motortiming to 3.2mm
-Change magnets regularly as the tend to fade which generates more heat
and less power
-The motor can handle up to 130°C. You are save up to around 110°C.
Attached Files
File Type: zip
V13_basic.zip (776 Bytes, 669 views)
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Old 09-07-2010, 01:29 AM
  #1852  
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Originally Posted by Martin Hofer
yzf: the telemetry only shows the correct value when you push the button shortly after you raced (that means the speedo saves the actual temperature)
Hello Martin
When you do that the telemetry shows only the last time you push the button or it can show all the values of one day of race if you push several times the button ?
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Old 09-07-2010, 01:33 AM
  #1853  
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only the last run
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Old 09-07-2010, 01:42 AM
  #1854  
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Thx a lot fot your tutorial !

Another thing what mode should we use for 0 timing races ?
Is it better to choose en stock mode and remove the timing or a modified mode where there is no timing yet ?
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Old 09-07-2010, 01:44 AM
  #1855  
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Just untick Highspeedtiming (HST) and HST with Switchpoint and you are in zero mode
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Old 09-07-2010, 01:59 AM
  #1856  
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martin my last question for today!

When i use the transmitter to switch from one mode to another, should i set on the transmitter the TH Brake at 100% or can I leave it at 70% ?
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Old 09-07-2010, 02:08 AM
  #1857  
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turn it up to 100 but if you always use 70 why not set 70 on the speedo. much easier
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Old 09-07-2010, 02:14 AM
  #1858  
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Originally Posted by Martin Hofer
turn it up to 100 but if you always use 70 why not set 70 on the speedo. much easier
Ok thx !
Sometimes i change it quickly and directly on the transmitter... But i agree the best is to set the correct value on the speedo.
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Old 09-07-2010, 11:43 AM
  #1859  
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Originally Posted by housey
The next track I'll be at is a little smaller/tighter guys,

[img][/img]

I was thinking around 7fdr, or is that still too high?

Would I be right in saying that the GM's are geared with a much lower FDR than other brands. People running other brands seem to have smaller pinions and let the system rev. Is that because the GM system as a combination has more torque?
Thats very similar to the style of track i was testing ratios on, even the same carpet. I got down to 5.8fdr with 5 degrees timing and I still think that ratio needs to go up a tooth more or two.
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Old 09-07-2010, 01:21 PM
  #1860  
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Anyone got a starting ratio for 10.5 GM motor at WLRC?
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