Lehner 3080 / 8 Brushless Motor ? fault

[mohanjude]

The 20kg is due to the weight of the lipo cells - I had 2 banks of 10S 6000MA - which works out to 37V @12000MA.

I also going to shed all the alloy including the alloy rollcage.

Thanks for all the tips - the motor is a Lehner 3080 /9 -> the amp draw was with me trying to stop the shaft with my fingers using a Leather glove. I would not let a motor just simply rev full blast. I must say my thick leather gloves got very hot!!

The bottom line is that I have taken the Lehner off the truck put the Bolido in their shed some weight by taking the heavy aluminium rollcage and only running one back of 10S 6000MA lipos. The trucks appears to run well and I will post some videos shortly. I will weigh the truck and give you the correct loaded weight including batteries.

Mohan

[lincpimp]

Originally Posted by mohanjude

The 20kg is due to the weight of the lipo cells - I had 2 banks of 10S 6000MA - which works out to 37V @12000MA.

I also going to shed all the alloy including the alloy rollcage.

Thanks for all the tips - the motor is a Lehner 3080 /9 -> the amp draw was with me trying to stop the shaft with my fingers using a Leather glove. I would not let a motor just simply rev full blast. I must say my thick leather gloves got very hot!!

The bottom line is that I have taken the Lehner off the truck put the Bolido in their shed some weight by taking the heavy aluminium rollcage and only running one back of 10S 6000MA lipos. The trucks appears to run well and I will post some videos shortly. I will weigh the truck and give you the correct loaded weight including batteries.

Mohan

Wow, that is alot of lipo! Anyways, sounds like you cured the issue. From what othello says the esc just does not like 2 pole motors... Seems weird to me.

Glad to hear that you did not let it run unloaded! 10s 6000 should do fine, loosing the weight probably helped too.

[mohanjude]

I changed the motor and controller - I started a new thread.

http://www.rc-monster.com/forum/show...041#post248041

Lety me know - I am a real chicken I am not opening it up on this narrow stretch of road.

I am looking forward to taking it to a field and given it a good blast. You can see in my first clip as soon as I gun the throttle this monster flips over.

Using a pretty similar setup with slightly less power my first hints would be to choose a shorter gear ratio and to use real high-amp connectors between Lipos and ESC (6 mm gold)!
As you know I'm driving the FG 4WD with a Lehner 3040/12, Schulze 32/170 and 8S2P (12 Ah). The weight of my monster is "only" 15 Kg but from my point of view the pinion or gear ratio is key in this weight-league.
The general problem of brushless-setups in such heavy cars is to overcome the initial startup due to the missing clutch. I could see from your pictures that you are using the original pinion (16/48). Try 14/48! It's only two teeth less but it makes all the difference.
Another way to prevent stalling might be to change the throttle EXPO in your RC. Just put it to + 100% and check it out. I am down to + 50% but I still use it.
Compared to the 40.160 the 32.170 only works up to 10S but it can face higher Amps. (up to 220 peak) and you can set up things like higher or lower timing and softer or harder running. I tried all those switches but they didn't have big effects.
As mentioned, key is the appropriate gear ratio.
The Schulze ESCs have a kind of self protection once they face a situation that they can't cope and they just stop to work - other than the BKs that try to do it until they burn (and I know the smell of burned BKs...).
BTW. 150 Amps. is by far not sufficient and that's the reason why I haven't used eagletree yet. At least at 8S you have to think about 200+ Amps. at the start.

Regarding the 4WD-thing I'll send you a message.

Last but not least I don't want to make you jealous but with the 3080 your monster should at least performe like mine:-)

http://www.youtube.com/watch?v=mZQR_Xubr8o

Regards,
Hermann

[mohanjude]

Originally Posted by E-VO-Maxx

Using a pretty similar setup with slightly less power my first hints would be to choose a shorter gear ratio and to use real high-amp connectors between Lipos and ESC (6 mm gold)!
As you know I'm driving the FG 4WD with a Lehner 3040/12, Schulze 32/170 and 8S2P (12 Ah). The weight of my monster is "only" 15 Kg but from my point of view the pinion or gear ratio is key in this weight-league.
The general problem of brushless-setups in such heavy cars is to overcome the initial startup due to the missing clutch. I could see from your pictures that you are using the original pinion (16/48). Try 14/48! It's only two teeth less but it makes all the difference.
Another way to prevent stalling might be to change the throttle EXPO in your RC. Just put it to + 100% and check it out. I am down to + 50% but I still use it.
Compared to the 40.160 the 32.170 only works up to 10S but it can face higher Amps. (up to 220 peak) and you can set up things like higher or lower timing and softer or harder running. I tried all those switches but they didn't have big effects.
As mentioned, key is the appropriate gear ratio.
The Schulze ESCs have a kind of self protection once they face a situation that they can't cope and they just stop to work - other than the BKs that try to do it until they burn (and I know the smell of burned BKs...).
BTW. 150 Amps. is by far not sufficient and that's the reason why I haven't used eagletree yet. At least at 8S you have to think about 200+ Amps. at the start.

Regarding the 4WD-thing I'll send you a message.

Last but not least I don't want to make you jealous but with the 3080 your monster should at least performe like mine:-)

http://www.youtube.com/watch?v=mZQR_Xubr8o

Regards,
Hermann

Hermann

Thanks for your detailed message. Did you read my bit about putting the motor on the bench and holding the shaft with my finger. I am not talking gears here - just my fingers. With the Schulze when the timing signal is increased to 0.154 (neutral is 0.150) the motor stalls. If I go straight to 0.157 then the motor will not stall. I will try expo which means that the motor will jump straight to say 0.160.

You are right about the BK's - I just love when I can smell them. I feel my wallet just going up in flames. What did you think of the Bolido? You dont think it is powerful enough?

Next week when Lehner opens his shop again I am going to ring him and ask what ideas he has.

My truck runs fine on the current gear ratio using the Plettenberg Bolido and the schulze controller. Why can't it run better on the Lehner 3080 which is a bigger more powerful and heavier motor.

I might be tempted to return the truck to the Lehner with bigger wires and bigger 8mm power connectors.

Mohan

Mohan

Unfortunately I have no technical background but I read your postings and I am wondering if this should be possible. But I am hesitant to try that too because I have sealed my pinions.

The Bolido is a very powerful engine but even the H+M guys that love the Bolido had to admit that the Lehner is able to outran the Bolido - based on the performance of my car.
A way different approach to controlling power in our cars might be a so called "Sinus-Leistungs-Steller".
I haven't tried it yet because it would be an approx 700 Euro-Check but this ESC promises to move a car like a trial-car but also be able to run very good top-speed.
If you check my favourites at youtube you can find two videos of a monster with this type of ESC.

Hermann