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Old 06-12-2009, 06:11 AM   #4261
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does anyone have any definite answers about the timing/boost advantages?

I mean,
1) max motor timing/0 boost
v's
2) 0 motor timing/max boost

I have not found which one of the combinations ended up better.

In theory, the max motor timing/0 boost will have less torque then option 2. But on track, my results are pretty much the same.
I'm wondering the same thing. Also which way to gear each. Well, I know how to gear #2.
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Old 06-12-2009, 06:53 AM   #4262
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I've got to say, some direction on this front would be ace!

I read on here that for smallish indoor tracks (20x10m or 66x33ft) you should run motor timing and low boost. Then someone else posts that you should run max boost and low motor timing everywhere! Contradicting advice, but nothing I've seen from Tekin.

Could Randy or the Prez please say difinitively what they would advise? Does one option definately give more tourque or more top speed?

I ask because my own testing has been inconlusive.
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Old 06-12-2009, 08:02 AM   #4263
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Anyone has a problem trying to get on the Tekin forum? I get a SQL error.
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Old 06-12-2009, 08:11 AM   #4264
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Anyone has a problem trying to get on the Tekin forum? I get a SQL error.
yep me to
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Old 06-12-2009, 09:01 AM   #4265
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anyone got a starting point FDR for 17.5 redline ?
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Old 06-12-2009, 09:16 AM   #4266
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anyone got a starting point FDR for 17.5 redline ?
Not w/o knowing the car type... 1/12, WGT, TC Rubber, TC Foam, etc...
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Old 06-12-2009, 09:51 AM   #4267
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TC rubber, small carpet track (60ft)
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Old 06-12-2009, 10:03 AM   #4268
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No need to Scotty has it at the track in the shop.
Yeah, folks have it at most spots I race...but it would be nice to have it in a more portable package. Plus all we have at home are apple computers...

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Old 06-12-2009, 10:53 AM   #4269
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Plus all we have at home are apple computers...

What's that?
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Old 06-12-2009, 10:54 AM   #4270
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They are computers that do it all. You probably have some of their products in your own home.
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Old 06-12-2009, 12:21 PM   #4271
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I don't know if this helps the timing debate, but...

First up, we need to distinguish between the angle of the sensors to the centre of the coils (theoretical zero), and motor timing. They are not the same thing.

A sensor is a Hall Effect switch - when it detects a magnetic field it sends a signal. The magnetic field does not go out in a straight line from the end of the rotor, it's like having a ball on the end. Depending on how strong the magnet is, and how close the rotor runs to the Hall Effect switch, depends on when the switch says "ahhh, there you are, I'll send a signal!"

The time at which the coil fires relative to the rotor position is the timing. That's what the software is doing, it's telling the coil to fire at 0 degrees, and when we add timing it fires (say) 20 degrees before 0.

So, to get the motor to fire at zero degrees with a rotor that has a weak magnet and is spaced further away from the Hall Effect switch, the sensor position will be in position 1. With a strong magnet run closer to the Hall Effect switch, the sensor will be in a different position 2, and the motor will still run a 0 degrees of timing. Two different Hall Effect sensor positions, both motors at zero degrees timing. The problem everyone has is that they don't know when the motor sensors are reading the rotor at zero degrees of timing!

So, when someone says their motor comes with 25 degrees 'timing' we don't know if that means the coil fires 25 degrees before 0, or if it means that the sensors are positioned 25 degrees from the centre of the coil just to ensure that the timing is 0 degrees.

In the BR days, timing was easy because the brushes were touching the comm, and all we had to do was see the angle of the endbell to know the timing. That's all gone. The only way you can know if the motor is timed at zero degrees is to have some device that can show it to you by reading the electronics. Frankly, you will never know when a motor is at zero degrees.

Today, because of different magnet strengths and different spacing of the rotor from the Hall Effect sensors, it isn't likely that any two motors will have the same angle from the centre of the coil to give zero degrees timing.

Your best bet is to take any zero mark from the motor or its instructions, and then add timing from there. Ignore any other information!! So, if Randy or Tekin Pres says 10 deg motor and 20 deg boost, add ten deg on the motor and set the boost to 20 deg. Don't worry about where that ends up in absolute terms, because it's not relevant!! Don't keep asking what zero is and all the other questions about angles of the sensors to the centre of the coil, because it's irrelevant.

1mm of arc on the can is about 3 degrees of advance. So, for 10 degrees, move the marker for timing about 3.5mm away from the fixed mark. I move my 'endbell' (LRP X11) marker anticlockwise (looking from the endbell) away from the fixed, etched marker on the can. For my 10.5 4-cell car, I have 3.5mm of rotation of the 'endbell' to give about 10 deg timing, and set the boost to 20 deg. I then gear for the speed and acceleration I am looking for bearing in mind the track layout - again, just as we did with BR.

It is no longer possible to give FDRs for any given car and track and expect them to work in another car on another track. All this software technology has done away with that. In addition, anyone who uses brakes a lot will end up with a significantly hotter motor than someone who doesn't, and drag brake is going to be a no-no if you want the top speed - waaaay too much motor heat!

To sum up - don't confuse the angle of the sensors to the centre of the coil with the angle required to add timing - they are not the same. Use the zero on the motor as zero, add the motor timing and speedo timing you want, and then gear accordingly. I hope that helps!
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Old 06-12-2009, 04:16 PM   #4272
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Spot on! Now include that we actually fire the winding before we get to the sensor when boosting timing above what is physically set in the motor.

Heat is always king! Start low and work up. Nothing has really changed since brushed motors except when you over shoot the BL motors do not burn up so easy.

All the motors we have looked at are in the 15deg range of extra timing so we really can ignore it... until we try to compare to sensorless where this does not exist.

We are working on a good explaination of the different timing settings. Fortunately you do not have to understand it all because we have a Randy and a great team of drivers that can tell you where to set everything for a starting point in any application. The short story is we have 3 levels of timing, the motor timing, boost timing and now turbo timing. Motor timing launches you from a standstill and carries you thru the first few feet. Boost timing is added with rpm and increases the acceleration, turbo timing is added over time when at full throttle and increases the motor rpm for top speed. In all cases if you have too much timing in any area you will create extra heat in the motor. Typically it will run good upfront, but die off a couple minutes in. Motor timing is the most dangerous because it is always there and easy to overgear. Motor timing is the launch and initial accel out of a corner. Boost can get you in trouble also and the one that lower gearing helps the most with. Boost is your infield rip. Turbo is pretty safe because it adds over time and unless you have a really long straight, 200', you will not get full turbo engaged even if you set the full amount. You also get to set the delay before it even starts.

In effect we have a 3 speed tranny which allows you to run lower gearing, get better launches and acceleration and still get good top speed with less overall heat…. In short it makes you go fast!

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Old 06-12-2009, 04:20 PM   #4273
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I wrote this for people in the Rx8 thread having radio calibration problems and I think it is worth sharing here also.

Radio calibration is pretty easy to diagnose whats going on. It is a pretty simple signal to deal with, so here is the nerd info for those that it makes sense for.

The radio signal is a simple pulse of 3V. It is suppose to be a square wave and we measure the high time. This pulse is sent every 5ms to 20ms depending on the radio, that is the frame rate you hear about. Shorter is high end radio since the signal comes more often, in fact too often for many servos and older speedos to handle which is why HRS does not work with all products. This is also where noise creates glitches.

If the square wave is messy we might measure a full throttle, then a half brake, then a half throttle, then a neutral in less than .1 sec and we react to each signal. The speedo does exactly what it is told. Speedos do not glitch unless they are told to. We do some DSP to smooth it out, but that can be tricky also.

The standard signal for the industry is really based on a servo and from before speed controllers. There really is no forward or reverse standard since a servo can be mounted either way. It is really a left, center and right signal. The standard is a 1.5ms pulse for center or neutral. In a speed controller most consider a 1ms pulse as full brake or reverse and a 2ms pulse as full throttle and those are the factory defaults in the RS. IE a 1.75 ms pulse would be half throttle, a 1.25ms pulse would be half brake.

Good radios typically have a 70/30 throw for throttle and brake. This means the center/neutral is about 1.3ms. Also radios have EPA adjustments that move the endpoints of the signal. IE with EPA’s at 100 the full throttle pulse may be 2ms and the full brake signal may be 1ms. If you increase the EPA’s to max the full throttle might be 2.2ms and the full brake might be .8ms. Since we have no idea where the center/neutral is or the endpoints we have to calibrate to the signal and learn them.

We are expecting a signal between 1.7ms and 2.4ms for throttle. If your radio is backwards it might be giving us a brake signal of 1.3ms to .8ms and we will not accept it. Many older speedos will take the signal either way. For diagnostic purposes we do not.

So if you start a calibrate and we accept the neutral, but will not accept the throttle we are not seeing what we want. If you push the brake and we accept that as throttle then obviously the signal is backwards and needs to be reversed on the radio.

As a diagnostic we have people unhook the motor and trick the unit into initializing. When the unit is turned on we are looking for the neutral. Since the default is 1.5ms and many radios are actually 1.3ms for neutral we will flash leds 1,2,3 to show that we see a signal but it is lower than we expect. If you pull the trigger it should change to flashing leds 5,6,7 to show the signal is too high. If the opposite is happening the signal is reversed. You can also move the trigger slightly until you find the neutral we want and get the unit to initialize. Then you can pull throttle and see if the leds react from left to right showing throttle. If they react right to left showing brake the signal is reversed. This also allows you to see how the trigger relates to the signal. IE if you pull full throttle and we only show 6 leds then the EPA’s are turned down and the signal is less than 2ms. If when you pull the throttle halfway all the leds are flashing the EPA’s are turned way up and you are giving us a 2ms signal at partial throttle. This is an excellent way to really see what the radio signal is.

Spectrum can trick you if the radio is not really talking to the receiver. They will give us a neutral signal that we accept, but when you pull throttle or push brake nothing happens and we still see a neutral signal from the reciever.

Another thing we have learned is the the unit will not calibrate the brake signal if you have any kind of antilock turned on in the radio. This varies the brake signal to us and we do not see enough consistent pulses to calibrate and store the value.

I hope this make it more clear to some and helps you get setup right. If the radio is working and giving us a signal within the ranges we expect, we will accept it. We have seen some radios where the trigger has slipped and signals are off significantly.

This concludes our NERD lesson for today.

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Old 06-12-2009, 05:10 PM   #4274
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Will the turbo make it easier to find the right gear?
Because when you gear it a bit lighter so you have good infield speed, the turbo will ad the little bit of top speed that you lost by gearing it lighter?

Tomorrow i'm going to drive with the Redline 10,5T. It's my best motor that i have and i didn't use it jet in the races because i didn't hath the change to test it.
Tomorrow i'm going to test it and find the right gearing.
I tested it earlier but at that time i used i think to much motor timing.
I will now use 3 on the motor and max boost.
Also can i check tomorrow my temp and compare my top speed with an other driver that drives with a LRP and a Tekin RS Pro.
When i tested it the first time i didn't hat the change to check the temp of the motor. So i didn't gear heavy. I found out that i hath a lot of infield speed. more than i have now but to low top speed.
Tomorrow i will try to get some more top speed. it will cost me some infield speed but i hope that the Turbo will come soon.
Than i have extra power for the fast parts of the track and a super infield power. Also i now for shore that my motor temp will stay low.

Will the motor get also hot when you gear to light?
Some other drivers that use a GM has that problem. I didn't hath that problem jet but can it get hot?
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Old 06-12-2009, 06:24 PM   #4275
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Quote:
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Spot on! Now include that we actually fire the winding before we get to the sensor when boosting timing above what is physically set in the motor.

Heat is always king! Start low and work up. Nothing has really changed since brushed motors except when you over shoot the BL motors do not burn up so easy.

All the motors we have looked at are in the 15deg range of extra timing so we really can ignore it... until we try to compare to sensorless where this does not exist.

We are working on a good explaination of the different timing settings. Fortunately you do not have to understand it all because we have a Randy and a great team of drivers that can tell you where to set everything for a starting point in any application. The short story is we have 3 levels of timing, the motor timing, boost timing and now turbo timing. Motor timing launches you from a standstill and carries you thru the first few feet. Boost timing is added with rpm and increases the acceleration, turbo timing is added over time when at full throttle and increases the motor rpm for top speed. In all cases if you have too much timing in any area you will create extra heat in the motor. Typically it will run good upfront, but die off a couple minutes in. Motor timing is the most dangerous because it is always there and easy to overgear. Motor timing is the launch and initial accel out of a corner. Boost can get you in trouble also and the one that lower gearing helps the most with. Boost is your infield rip. Turbo is pretty safe because it adds over time and unless you have a really long straight, 200', you will not get full turbo engaged even if you set the full amount. You also get to set the delay before it even starts.

In effect we have a 3 speed tranny which allows you to run lower gearing, get better launches and acceleration and still get good top speed with less overall heatů. In short it makes you go fast!

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I dont really agree with motor timing statements you made.

motor timing, to me anyway, affects not just the initial first few feet, but the entire power range. I know this is an onroad forum, but when I apply full throttle, and then change the timing, I can physically see the tyre expand considerably! More motor timing equals less torque, and more rpm. So your statements are very contradictive to what actually happens in real situations.
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