MikeXray

iTrader: (73)

Hey Randy, any chance we could get some feedback on this issue?
http://www.rctech.net/forum/electric...esc-issue.html

DaveW

iTrader: (1)

In regards to the above posts, i have had similar problems with my Tekin RS. This post is only to share my findings/situation.

My RS would stutter at startup, unless the motor shaft was initially spun by hand. Then the motor would spool up, and the lights on the RS would show full throttle. If i dropped to half throttle and brought it back up to WOT, the lights would do the same on the RS... but the motor would clearly sound either faster or slower each time. If i let off the throttle and waited for the motor to stop, 80% of the time it would start up on its own. If i went from WOT to full brake, i had to spin the shaft to get it started again... or it wouldnt start again at all. Each time i goosed the trigger for throttle, the motor would stutter and make varying squelching sounds. The motor would then get extremely hot.

Let me tell you what all i have done/changed, convinced this was a loading software or sensor issue.

2 LRPx12 17.5 motors
1 LRPx12 13.5 motor

This includes just sensor swaps in each motor to verify it wasnt a Precisensor or motor stack issue. Timing inserts were tried in 0, -5, and -10 positions. Positive physical timing wasnt tried for obvious reasons.

1 Speed Passion 13.5 motor
1 Speed Passion 10.5 motor

Both Speed Passion motors are unaltered.

All 5 motors worked prior to, and after this testing on another brand 'X' speedo.

Sensor wire was also swapped out, methodically on each motor and replicated the test procedure.

As far as software goes, i have loaded and loaded and loaded until i never want to open Hotwire again. Each time i changed motors or the sensor wire, i reloaded the software to the RS, and reprogrammed my transmitter. I tried rolling back the software, and updating to BETA 203. That DID actually fix one thing. I set Turbo delay to .5 to be able to hear if there was a change in motor RPM. After the second time i updated to BETA 203, i could hear the motor hit max RPM, then bump up a little higher. It didnt do that before. If i replicated the previous tests, the results were the same... and the motor got hot even faster. The speedo even got up to the 4th led for temp. It didnt do that before.

Now all of these tests were bench tests... not track tests. I would imagine my issues would have been partially masked except at startup. Tapping the brakes wouldnt bring the car to a complete stop, so the shaft would be spinning from the driveline and let the speedo start the motor. So for those guys that seem to have similar issues, try testing the setup with the motor unloaded.

If the issues went away when i went to the unaltered Speed Passion motors, i might lean towards the discussion of advanced mechanical timing found in the LRP's. Im not convinced. I can see the need to reduce RS timing considering advanced physical motor timing, but i dont think that is relevant to these issues.

Oh, and the cherry on top of all this? This was a NIB Tekin RS speedo. Im hoping that the one i get back from Tekin works great. Since i started racing in 1994 i have never had to send a speedo back for repairs... until now.

M-Technic

iTrader: (15)

After all that bench testing, what actually happened when you put the car on the track with a load?

I ask because sometimes my motor stutters at low RPM with no load, but it has absolutely 0 effect once the car hits the track. It never cogs, stutters, or fails to start on the line.

Capt'N_Slow

iTrader: (10)

I have been using the following item from digi-key to replace the stock cap once it lets go.

Nichicon CAP POLY ALUM 470UF 16V RADIAL LOW ESR (9mohm)

For 4.8V/3.7V pan car use I have been using one or two of the following as replacements.

CAP 680UF 10V ELECT POLY RAD LOW ESR (7mohm)


The cost is a bit high per unit does anybody else have another source?

DaveW

iTrader: (1)

It never made it out of the house. Once installed in the car and set on the floor to check steering trims and such, was when it did this. I had to punt it with my foot to get the car to move forward. lol Thats why all the bench testing followed.

I wanted the RS to work sooo badly. My VFS-1 just doesnt have the top end all the other RS owners have. Im talkin 4mph less at the end of the front straight... each lap (motor temp 180-190 degrees after a 6:30 run). I can make up a lot of that in the infield but thats pushin the car hard, every lap.

PitNamedGordie

iTrader: (8)

That definitely sounds like a sensor issue of some sort. I have a broken sensor plug on one of my RS's. I found out it was broken because my car would squeal and shutter unless I pushed it with my foot. When I pulled the sensor wire off the white sensor plug came with it. I never sent it in to get it fixed, but I remember when I called it in they said they would replace the top board on the ESC....for like $80?..but don't quote me on the price. If I were you I'd call Tekin and go over the testing with them. They always answer and are very helpful.

yodace

iTrader: (8)

Does Ne1 have setup for a tekin 13.5 and RSPRO 100x65 outdoor asphalt track?

DaveW

iTrader: (1)

Gordie, i know what ya mean. I was convinced it was sensor or sensor wire related as well. I tried Dual Mode, sensor wire removal, etc. I mean, it was a new speedo, so the last thing you think would be wrong is the new item you just purchased.

I did call Tekin, and we talked for a bit about the issues i was having. They were very helpful, and gave me an RA# to warranty the RS. No complaints at all so far.

20 SMOKE

iTrader: (103)

this should get you started
http://www.teamtekin.com/hotwire/ESC...dium-Track.pdf

DrBen

Im still trying to understand the inital idea of turbo vs. boost..
The boost makes completely sense to me: the faster the motor turns, the more timing I add, considering the factors rpm, torque, heat and efficiency.

I also understand that turbo will add even more timing on top of boost.
But what I dont understand: Why is this based on a time delay?

Using a fixed time for the turbo to kick in includes quite a few variables into the equation (track conditions, car weight, actual point when WOT is applied, etc.) the moment when the extra timing kicks in needs to figured out by guessing and trying.
For a given straight, you might well arrive at a good point, and get the turbo to kick in at a certain point when its beneficial, but if you have different straights on a track (or want to use the same setup on different tracks) this might not hit the sweet spot at all times.

For my understanding, it would make more sense to base the turbo timing on rpm, same as the boost.
Lets say I run 40 boost (5k-20k), and 15 turbo (0.6), and this makes the turbo kick in roughly at the point where 20k rpm is reached.
Without turbo, the acceleration would ease off at 20k, and the motor would maybe spool up to 22k. With turbo, it would accelerate a bit more, and maybe spool up to 24k.
--> What would be the difference in performance when I increase boost to 55 and the rpm range to 5k-24k, and set the turbo to 0?
Im thinking this would allow the extra 15* to come in much more accurate and smooth,
compared to adding it via time delay, where its likely to kick in a bit before or after 20k.

The only advantage of turbo I can see is the steeper ramp at the end, so more timing is applied in a shorter time.
But again my lack of understanding for the time delay: Why is the turbo not based on rpm? For a steeper timing ramp on the upper rpms, the turbo could have an rpm range as well, and I would set 40 boost (5k-20k) and 15 turbo (20k-24k).

I read alot in this thread, but looking at the number of posts, it might well be that I missed something.
If some of the gurus on this board could elaborate on the above or point me to the right posts, that would be greatly appreciated!

20 SMOKE

iTrader: (103)

in a quick lay mens term,if turbo come in to soon it will create to much heat,with the rpm range and delay you want to make the curve of rpm as economical as possible.you have the right idea on watch your talking about but i think you are thinking to hard

dawgmeat

iTrader: (9)

Jamie do you have a 10.5 ballistic set-up

20 SMOKE

iTrader: (103)

no just start with a 13.5 conservative setup and go up.start with no turbo and bring it up slowley.where are you running a 10.5

dawgmeat

iTrader: (9)

k raceway

DrBen

exactly, turbo too early will cause too much heat and less efficiency, and turbo too late will cause less speed. So why not base it on rpm and have a very accurate application of the extra timing?

"Thinking hard" seems to be my fate.. but it feels so good to understand things in the end