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Old 06-21-2010, 02:09 PM   #15241
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I've got 2 Tekin RS Pros. I got one when they first came out and one a few months back.

The first one I got had rubbish brakes, I posted a few times about it without resolution. I tried different motors, boost and turbo settings, FDRs, spur and pinion combinations, reloading software versions, lowered brake settings and all sorts. Nothing worked. For those that say you are locking up the tyres, that's highly unlikely unless you're racing on ice or incredibly low traction tracks. Here's something to try, put your car on the ground, apply the brakes and gently nudge your car forward and I bet you'll see the wheels are turning, even if you do it on laminate flooring.

The second one I bought had fantastic brakes straight from the off.

I solved the problem of rubbish brakes on the first one by making the speedo a forward AND reverse speedo and then turning reverse down to 12%. That's not enough to make it move backwards on the track, but it sure as hell stops the car when you want it to. Oh, and the brake test above will still show the tyres turn when you apply brakes and nudge the car forward with your foot, but when you hit the brakes on the track, be prepared for a nice surprise

As to why I needed to make that change, who knows...
Tim - thanks for the info.

Just tried your test and sure enough I could nudge it forward very easily.

Have changed speedo settings as suggested and have noticed a difference in the time it takes for the wheels to stop when fully revved out on the table (not for very long though!) against before without the reverse settings applied.

Will test at Aldershot on Sunday.

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Old 06-21-2010, 02:25 PM   #15242
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My brakes seemed to get softer when i increased the timing boost. I usually turn my brakes down 20% or so, but this weekend i had them maxed out. I also ran different EPA's this weekend compared to before, in an attempt to resolve my previous turbo loss.

As far as brake lockup goes, um yeah. I can definitely get them to lockup and the car to slide... you can even hear it in the tires. The tires squeal is a great indication of the cars cornering, throttle, and brake attitude...
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Old 06-21-2010, 03:22 PM   #15243
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Originally Posted by THancock View Post
I've got 2 Tekin RS Pros. I got one when they first came out and one a few months back.

The first one I got had rubbish brakes, I posted a few times about it without resolution. I tried different motors, boost and turbo settings, FDRs, spur and pinion combinations, reloading software versions, lowered brake settings and all sorts. Nothing worked. For those that say you are locking up the tyres, that's highly unlikely unless you're racing on ice or incredibly low traction tracks. Here's something to try, put your car on the ground, apply the brakes and gently nudge your car forward and I bet you'll see the wheels are turning, even if you do it on laminate flooring.

The second one I bought had fantastic brakes straight from the off.

I solved the problem of rubbish brakes on the first one by making the speedo a forward AND reverse speedo and then turning reverse down to 12%. That's not enough to make it move backwards on the track, but it sure as hell stops the car when you want it to. Oh, and the brake test above will still show the tyres turn when you apply brakes and nudge the car forward with your foot, but when you hit the brakes on the track, be prepared for a nice surprise

As to why I needed to make that change, who knows...
The brakes on a brushless motor just don't work that way.

I dont' know the exact science behind it, but it has to do with the speed in which the motor is spinning. The faster it is spinning, the more brake power you get when you apply them. If you are standing still or moving just a tiny bit, braking power will be really weak, no matter how strong you make them.

For example. I run 17.5 and run my brakes at a medium setting (forget the exact setting off hand)... just strong enough to let me brake hard charging/diving into a corner... but not strong enough to get the car sliding. So at 30+ mph, the brakes come on pretty strong and the car stops great. But, if I am rolling my car around the track at 1mph.. the brakes barely stop it at all.

So sitting the car on the ground at a stand still, and seeing how easy it is to push the car forward, isn't ANY kind of test to see how strong your brakes are while driving the car.
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Old 06-21-2010, 06:39 PM   #15244
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You're correct. Brakes on ep cars don't work that way.

I've read about these issues in the SP/HW and MambaMax forums too.. I have em' all and have never had any issues with brakes. Mine is always turned down to about 60% for more control. I wonder if its the radio settings for those having issues.. Especially with the newer high end radios with hundreds of setup options like ABS, Throttle speed bla bla...
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Old 06-21-2010, 06:48 PM   #15245
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from what i can say is that timing does affect braking power. there were timesi had brilliant brakes and times i could use full braking but it just stopped like a old worn handbrake... in about two weeks im heading back to the track as i am in exams right now. i think i can put some time in this as i realy lose time in one particular corner because i have to brake a 1second earlier to get it to stop properly for the hairpin! tried a fresh cap, didn't work. i use 100% brakes on both my RS and my transmitter.
the thing i also notice is when revving in the free air is that when you put like 50% throttle on and then decrease to like 10% this goes way faster than when from 50% to full brake! strange!
maybe i could give this reverse trick a shot...
im running a LRP x11 10.5 on a fairly large 1:5GP track.
all timing on max! max boost, max turbo, max on motor, fdr: 5.33 but still only getting 85C!!! im like overtaking 1:10 nitro cars on the back straight as well as going as fast as the mod cars. I LIKE!
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Old 06-21-2010, 11:33 PM   #15246
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re phrase your ? how does SP/HW stack up to a Tekin
Enough said lol.
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Old 06-21-2010, 11:58 PM   #15247
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what would u guys recommend setting the motor timing for tekin 13.5 ? For outdoor asphalt 120 x 65.

Running Randy Pikes Tekin Rspro 13.5 setup> fdr 7.06 T3
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Old 06-22-2010, 02:02 AM   #15248
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what would u guys recommend setting the motor timing for tekin 13.5 ? For outdoor asphalt 120 x 65.

Running Randy Pikes Tekin Rspro 13.5 setup> fdr 7.06 T3
Stock setting from the factory.
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Old 06-22-2010, 02:59 AM   #15249
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I dont' know the exact science behind it, but it has to do with the speed in which the motor is spinning. The faster it is spinning, the more brake power you get when you apply them. If you are standing still or moving just a tiny bit, braking power will be really weak, no matter how strong you make them.
The difference is likely to be negligable. If it were as strong as you suggest, hitting brakes from 34k RPM compared to 0 RPM would rip the transmission right out. But it doesn't.

The fact here is that some Tekin speedos have rubbish brakes. Why? Nobody seems to know.

I have one that stops instantly when moving slowly (which shatters the rotor RPM theory - excuse the pun) and stops in about 3 to 4 metres from 40mph at 34k rpm. I have another that stops instantly when moving slowly, but takes about 7 to 8 metres to stop from full speed. The full speed braking for that speedo is only fixed by turning the reverse on at low power.

Forget all the timing and RPM theories because you've probably got one of the speedos with good brakes straight out of the box.

And if people are locking their tyres up on a high grip track, it's either not as high grip as they think, their car setup is making the car bounce or they're not braking in a straight line so the tyres are trying to steer and brake at the same time.

Oh, and I should add, I buy all my own gear and I really like my Tekins (now at least) so this isn't a bashing by a fan boy of another manufacturer.
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Old 06-22-2010, 04:03 AM   #15250
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I have one that stops instantly when moving slowly (which shatters the rotor RPM theory - excuse the pun) and stops in about 3 to 4 metres from 40mph at 34k rpm. I have another that stops instantly when moving slowly, but takes about 7 to 8 metres to stop from full speed. The full speed braking for that speedo is only fixed by turning the reverse on at low power.
When you turn on the reverse at low power, does the distance to stop also go down to about 3 to 4 meters like the other and does it feel the same?
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Old 06-22-2010, 05:12 AM   #15251
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Originally Posted by THancock View Post
...
The full speed braking for that speedo is only fixed by turning the reverse on at low power.
...
Can you please explain how to configure things in order to use reverse as a brake assist. In general, ESC firmware only engages reverse after the car has stopped (rpm zero). Not sure on the behaviour of the Tekin RS ESC firmware in regards to reversing.

Thanks in advance
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Old 06-22-2010, 05:19 AM   #15252
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When you turn on the reverse at low power, does the distance to stop also go down to about 3 to 4 meters like the other and does it feel the same?
Yes, using 12% reverse strength makes the car stop in 3 to 4 metres and it feels the same as my other Tekin with good brakes.
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Old 06-22-2010, 05:27 AM   #15253
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Can you please explain how to configure things in order to use reverse as a brake assist. In general, ESC firmware only engages reverse after the car has stopped (rpm zero). Not sure on the behaviour of the Tekin RS ESC firmware in regards to reversing.

Thanks in advance
I set the speedo type to BL-FR which is the reverse with no delay option. Leave the brakes at 100% (because they were rubbish anyway) and set the reverse strength to 12%.

I've not noticed any change in motor or speedo temps with this setting, but I don't use brakes unless absolutely necessary.
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Old 06-22-2010, 06:42 AM   #15254
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Originally Posted by THancock View Post
I set the speedo type to BL-FR which is the reverse with no delay option. Leave the brakes at 100% (because they were rubbish anyway) and set the reverse strength to 12%.

I've not noticed any change in motor or speedo temps with this setting, but I don't use brakes unless absolutely necessary.
ditto, although I do run around 30% on the reverse, but this is with 10.5 so it may require a bit more.

It does make a big difference to the brakes but also doesn't seem to take much more out of the cells either.

My Nosram and Black Diamond are capable of locking the wheels if provoked very hard.

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Old 06-22-2010, 07:32 AM   #15255
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I set the speedo type to BL-FR which is the reverse with no delay option. Leave the brakes at 100% (because they were rubbish anyway) and set the reverse strength to 12%.

I've not noticed any change in motor or speedo temps with this setting, but I don't use brakes unless absolutely necessary.
Thanks - I'll try this weekend
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