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Blf
2017.01.10, 11:45 AM
I know Arch2b has similar issue but getting cogging on light throttle in both directions on one of my gp chassis in LM confg:

https://youtu.be/rowLbXn7tU0

I'm slowly increasing throttle and it cogs then finally moves - tried putting travel back to 100 both directions already.

Why would this happen all the sudden?

briankstan
2017.01.10, 12:24 PM
to reduce the cog try changing the gearing you can keep the overall gear ratio but go with a smaller pinion. also there a some changes you can make on the board with the ICS that helps as well. the setting that affect the torque.

cowboysir
2017.01.10, 02:14 PM
I find it happens to me most often with batteries that aren't at their peak...just a suggestion.

Blf
2017.01.10, 03:23 PM
I tried different cells/fully charged etc..... I just don't get why it would happen on one and not the other chassis. A contact a Kyosho said he doubts the ICS settings will help.

Do others have it like this? Arch? I know Larry said he was unable to bind but nothing on cog like that. The car is feeling/running great when it gets going but man...

Brian - I would try a lesser pinion ( I have 9t Derlin on both now) but again, my other car with same setup essentially is not cogging. Is that a motor OR board issue maybe?

briankstan
2017.01.10, 03:57 PM
I tried different cells/fully charged etc..... I just don't get why it would happen on one and not the other chassis. A contact a Kyosho said he doubts the ICS settings will help.

Do others have it like this? Arch? I know Larry said he was unable to bind but nothing on cog like that. The car is feeling/running great when it gets going but man...

Brian - I would try a lesser pinion ( I have 9t Derlin on both now) but again, my other car with same setup essentially is not cogging. Is that a motor OR board issue maybe?

I would give it a shot and see if it goes away. might just be slight differences in the motors.

EMU
2017.01.10, 04:36 PM
Have you tried swapping motors with the car that does not cog to see if it is a motor or pcb issue?

Blf
2017.01.10, 06:06 PM
Good points guys ----- I actually saw an improvement from standing start with progressively more throttle with a stock 7t -----but still there a little. But its showed definite improvement.

Man those pinions are loud though --- are there any derlin options in 6t and 7t? The Pro 2 Derlin with set screw locking are what I use normally (and working perfectly with the other GP BTW)

I'll maybe just try a stock VE Xspeed maroon colored motor I have drilled here to see if its any different.

lfisminiz
2017.01.10, 06:27 PM
The PN 3500 is smooth. Also try 64P. gears...smoother and more quiet. Not sure what you have on now.
On another note...as far as binding issues for me, i believe i may have puffed the board by putting the wrong batteries in accidently. Regular AAA/LIPO AAA. Tried another VE board and all is good.

Blf
2017.01.10, 10:33 PM
Wow on the boards frying - on that note, kyosho thinks it's maybe motor wires damaged or the board itself. Anyone ever have that happen?

I did remember making a tiny nick in the esc wire when cutting the original zip tie holding the wires to the motor case to keep them out of the way. I covered it with a pinhead of bondic and thought nothing of it. Could that be the cause?

The is car feeling fantastic around the track otherwise - I love it

arch2b
2017.01.11, 06:55 AM
for me it's not the motor. I tried the kyosho red and blue, atomic 5500kv, and pn 3500kv. some are worse than others. unfortunately i tossed the kyosho motors thinking there was something flawed in the motors as they were drilled and tapped :rolleyes: that was a costly mistake. I'm giving up on brushless for the time being. i simply do not have the time to deal with a finicky car anymore, much like F1. time is better spent on properly taking care of my other cars instead of endless troubleshooting on one in particular.

good luck to you though, i'll be following this just in case i bring my VE Pro board back out and put into something.

Blf
2017.01.11, 07:03 AM
I hear you on not wasting time chasing issues - I'd rather be running/maitaining the "good ones" in my arsenal but I always try to save the problem cars

I'll try a new motor and see if it's the board I suppose first

Blf
2017.01.11, 09:53 AM
Update:

Just put a brand new Burgundy colored xspeed ve in and not a cog sight..... Does that mean it definitely the motor or is it maybe still the board and how it interacts with the 12000kv?

Kevinmueller
2017.01.11, 11:38 AM
Hey I have had the exact same issue as you have described. It happened to me when the engine became very hot during one particular run. I believe what happens is that the small protective film around the wire coils wears out and a short is made in the wires (maybe this happens because the rotor expands and makes contact with the wires, I noticed the magnet casing had some scratch marks, or the film simply overheats and dissolves, I'm not sure). I tired to apply some glue to the coils in an attempt to stop the short and this did make the engine work again, but only temporarily, as the engine heated back up it started to cog again. I haven't found any solution yet other than what you did which is to replace the engine. But for sure this is not the same issue as having poor batteries, connected wires to the engine or even a fet issue as I already tried all those possibilities. If you could check your rotor and let me know if you see any scratch marks maybe one of my theories could be correct.

Blf
2017.01.11, 04:33 PM
I'll take a look - yes it's running great with the xspeed ve that came with a ve pro

Larry, on th 64p recommendation, can I use the 51 tooth spurs from reflex with an otherwise stock kyosho ball diff? Looks like it just requires using a bearing in the center and then just use the kyosho plates / housing e clip etc?

lfisminiz
2017.01.11, 06:12 PM
I'll take a look - yes it's running great with the xspeed ve that came with a ve pro

Larry, on th 64p recommendation, can I use the 51 tooth spurs from reflex with an otherwise stock kyosho ball diff? Looks like it just requires using a bearing in the center and then just use the kyosho plates / housing e clip etc?

As long as the REFLEX spur is 64P, yes. Which i believe thats all they made. I assume with some work, dont exactly remember anymore, it would work with Kyosho diff. Im thinking maybe the inside hub needed some sanding?
Ive been using the PN complete diff. for a long time now.

Blf
2017.01.11, 11:15 PM
Good deal - I'll give it a shot

Blf
2017.01.29, 12:40 AM
To revisit this l, I tried a red xspeed brushless and it ran great then when my new 12000kv a just arrived putting one made it worst - it actually stopped and was acting like it does if you unplug just the red wire

I noticed the red esc wire seemed like it's female plug was loose and sure enough it came off! Maybe this was it all along?

I'm going to try another proboard but I noticed my friends brand new gp was tough to get in reverse as well today.

I actually secure the extra wires over the chassis in front of top shock - do you thing the heat from the car is messing up the es wires internally??? Just trying to figure this out.

My other gp 98mm car is absolutely fantastic with hardly any cog to speak of

byteme909
2017.02.01, 09:23 PM
Just curious if people are having issue with the new VE Pro car and boards or if its just brushless boards in general (VE and VE Pro). I was thinking of acquiring a brushless car to mess around with but news of cogging etc makes me want to keep investing in my asf brushed cars instead.

Blf
2017.02.03, 08:28 PM
I just tried two new 12000kv motors on my cogging gp ( ve pro board) and still acting this way - seems like you have dying batteries when you get on it out of a turn and stay on power? So I switch ed to a new ve pro board and same thing. What leads me back to the motors is that I still have an unmolested GP VE PRO with a 12000kv that's perfect and barely cogs.

The other two will cog especially in reverse but even in fwd sometimes from a stop/ during recovery from a screw up on track.

So are the 12000kvs that unreliable?

Blf
2017.02.03, 08:30 PM
Just curious if people are having issue with the new VE Pro car and boards or if its just brushless boards in general (VE and VE Pro). I was thinking of acquiring a brushless car to mess around with but news of cogging etc makes me want to keep investing in my asf brushed cars instead.

It's gotta be the motors - none of the ve pros with 8500kv red xspeed motors act like this, even when I swapped one in the car in question on this thread.

Traveler
2017.02.28, 04:00 PM
This is discouraging. Was looking forward to building my first brushless Z.

TeeSquared
2017.02.28, 05:00 PM
It's gotta be the motors - none of the ve pros with 8500kv red xspeed motors act like this, even when I swapped one in the car in question on this thread.

Makes me wonder if poor quality enamel was used to insulate the motor windings. It's a stretch (Need to emphasize this!) but take the motor into a pitch dark room and let your eyes adjust. Once you've done that, try and run the motor with a bit of load on it and peer inside the can to see if you can spot any arcing. I saw this once or twice many years ago on hand-wound, home-made CD ROM out-runner brushless motors on higher voltages so who knows if this will work for in-runners on low voltage. Could have been the frequency ramp/profile of the old ESCs I was using too.

If anyone has a better method than my redneck technique than please comment :o Unfortunately you can't use a DMM to check winding resistance because you usually need high frequencies to expose weaknesses in the windings dielectric strength.

byebye
2017.02.28, 07:10 PM
I've personally gone to all brushless except one for our clubs box stock racing. I haven't experienced any issues related to boards. I did experience a couple bad brushless motors. I wouldn't count the VE stuff out. I've had real consistency with the Atomic 5000kv motors however.

Kris