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Hi All, long time lurker first time poster here.

I’m having an issue with a recently bought second hand GF01… when I go full throttle it just cuts out and stops accelerating. If I pump the throttle it can go quite fast but towards the very high end it dies. It doesn’t wheelie like it should and if I do manage to get it to wheelie after reversing and then a quick throttle forwards, it won’t sustain the wheelie like I’ve seen it do on YouTube videos.

One of the main reasons I wanted a GF01 was because it’s supposed to be a wheelie machine, right? 
 

It has just a 27T Tamiya Silver Can brushed motor, but it should still pop wheelies with that. And obviously it shouldn’t be cutting out on full throttle. 
 

Does anyone know what might be going on?

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Sounds like the ESC cutting out. Full throttle from a standstill draws a lot of power and if the ESC is faulty, it can cut out. When you pump it, it spreads out the surges in power demand.

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Sounds like it might be a battery issue to me. Do you have another fully charged battery you can try?

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I’m using a brand new fully charged Overlander 3300 NIMH battery, brand new DumboRC X6PM 350 transmitter with X6FG receiver but I don’t know the brand or model of the ESC, which came with the car and is second hand. Here are some photos of the ESC, does anyone recognise what one it might be? It has no branding on it, looks like the sticker it once had has peeled off.

IMG_7661.jpeg

IMG_7662.jpeg

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It is indeed an Mtroniks ESC. Based on the configuration of the cables and calibration button, I'd guess a Sniper RV12. This suggests a possible cause of your troubles. In my experience (I have 7 of them), these ESCs don't always have the same stock endpoint parameters as most other radio gear. About 90% throttle on the transmitter equates to full throttle on the ESC. Full throttle on the transmitter overshoots the endpoint on the ESC, confusing it and causing it to cut power to the motor. I found that if one lowers the endpoint adjustment on the transmitter to about 90% and then recalibrates the ESC, everything works as it should. 

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15 minutes ago, TurnipJF said:

these ESCs don't always have the same stock endpoint

The same can be said of any 'auto' ESC. 1060s, for example, hits 100% at about 60% TX input.

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2 minutes ago, alvinlwh said:

The same can be said of any 'auto' ESC. 1060s, for example, hits 100% at about 60% TX input.

True, but most of them hit 100% and keep going. The Mtroniks sometimes have the unfortunate habit of cutting out if their endpoints are exceeded. 

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6 minutes ago, alvinlwh said:

The same can be said of any 'auto' ESC. 1060s, for example, hits 100% at about 60% TX input.

I realize I may have had the same sort of issue as the OP with a 1060, using two servos (25 kg) and a silver can. Trying to reverse full throttle with this combo cuts the ESC. Pumping the throttle works. Does it have to do with that the ESC has a 60A limit forward, but 30A going backwards? I am anyways replacing the 1060 with a 1080, but it surprised me when it happened.

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22 minutes ago, TurnipJF said:

True, but most of them hit 100% and keep going. The Mtroniks sometimes have the unfortunate habit of cutting out if their endpoints are exceeded. 

You are right! They even acknowledge it themselves!

SLRqD0z.jpeg

 

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10 minutes ago, JimBear said:

1060, using two servos (25 kg)

No, in your case, it is likely a BEC issue. Your 2 servos can draw up to 2 x 7A (depending on type, brand, etc) while the 1060's BEC only can do 3A, 5A at peak. 

Baring faults elsewhere, you probably will be better off using a UBEC for such a setup.

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I do like the way I can hang out on this forum and learn things from other people asking and answering questions.

For those of you that knew of this issue, when you build a car do you always spend time tweaking Tx settings to tune things like the throttle % at end of stick travel? for example

1 hour ago, alvinlwh said:

1060s, for example, hits 100% at about 60% TX input

If you built a car with a 1060 would you always adjust the Tx to match its output to the ESC max before considering the build complete?

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Thanks for your help everyone, I’ve managed to stop it from cutting out on full throttle by recalibrating the ESC. But it still won’t pull wheelies on demand like I’ve seen on YouTube. It seems as though it’s not accelerating hard or fast enough to wheelie.

The GF01 with stock parts is a wheelie machine, right?

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5 minutes ago, BennyRocket said:

The GF01 with stock parts is a wheelie machine, right?

It isn't as prone to wheelies as, say, a WR-02 or CW-01, but it can wheelie with stock parts. The reason I prefer driving my GF-01 over my WR-02 is because it doesn't wheelie as much, and tends to handle better as a result. 

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51 minutes ago, Gebbly said:

If you built a car with a 1060 would you always adjust the Tx to match its output to the ESC max before considering the build complete?

Yes, just observe the light on the 1060 and adjust EPA down until it starts to flash, then up by 2 or 3%.

iRNDI9A.jpg

A random 1060 equipped car that I have, 79% means the light goes solid at 76 - 7%.

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11 minutes ago, BennyRocket said:

But it still won’t pull wheelies on demand like I’ve seen on YouTube. It seems as though it’s not accelerating hard or fast enough to wheelie.

The GF01 with stock parts is a wheelie machine, right?

Some changes that will help.

1. Lipo, on my Lunchbox, I actually had to downgrade my motor from Sports Tuned to silver can after I started using lipo to prevent excessive wheelies.

2. Change to the smaller pinion if you haven't already. Small pinion means more torque, but less top speed. 

3. The GF has more weight to the front due to the 4WD vs my WR which is so light at the front that I actually use brass crawler wheel hexes to weight the front down. Adding some weight to your rear may help to get wheelies.

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3 minutes ago, alvinlwh said:

Some changes that will help.

1. Lipo, on my Lunchbox, I actually had to downgrade my motor from Sports Tuned to silver can after I started using lipo to prevent excessive wheelies.

2. Change to the smaller pinion if you haven't already. Small pinion means more torque, but less top speed. 

3. The GF has more weight to the front due to the 4WD vs my WR which is so light at the front that I actually use brass crawler wheel hexes to weight the front down. Adding some weight to your rear may help to get wheelies.

Great tips, thanks. Would using a Tamiya TBLE-02 ESC be a better option for this car?


I was hoping to stick to Nimh batteries but guess I could put a Sport Tuned motor in for more power?

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15 minutes ago, BennyRocket said:

The GF01 with stock parts is a wheelie machine, right

My GF-01 has the torque tuned motor that came with it and a 1080 ESC. It can wheelie from a standing start but it does so less than some of the youtube videos I have seen.

Something else to consider is the further back your centre of gravity is the more likely it is to wheelie. I deliberately placed my electronics further forwards and included things like an aluminium motor mount/heatsink to move my centre of gravity closer to the centre of the car to reduce wheelies. Conversely if you wanted to encourage wheelies you could try moving any weight further to the back and lightening the front.

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I have a GF-01 Heavy Dump Truck with a 3300mAh NiMH battery, a Torque Tuned motor and an 18T pinion all controlled by a Carson Dragster ESC.  It wheelies like a champ and does forward rolls on demand  :D

I'd make sure you have an 18T pinion and consider swapping the ESC, maybe it doesn't give as much initial punch in order to wheelie nicely?

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1 minute ago, BennyRocket said:

hoping to stick to Nimh batteries

My torque tuned motor and 1080 ESC are working fine with a NiMH battery fine and I would expect a sport tuned motor to work fine to if you wanted to switch motor but keep the NiMH.

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7 minutes ago, BennyRocket said:

Would using a Tamiya TBLE-02 ESC be a better option for this car?

I tend to stay away from the TBLEs, had too much problems with them.

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2 hours ago, alvinlwh said:

You are right! They even acknowledge it themselves!

SLRqD0z.jpeg

 

Well good god.

I bought the two WR02 tractors ages ago in a lot of stuff and both had issues with the throttle.....they both have mtronics ESCs...

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Does anyone know if you can tell if a GF01 has a full metal bearing set installed without taking it all apart?

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