• Welcome to Tekno RC Forums! Are you a Tekno RC fan? If so you're in luck as you've have arrived to the biggest and best Tekno RC community.

    Come join our community and ask your questions, show off your Tekno RCs and share your experience!

Talk Servo's!!!

Ifti

Well-known member
Messages
401
Reaction score
263
Location
UK
Interesting article here with the EB48 2.0 : https://www.promodeler.com/caseSTUDY/Servo-for-a-comp-buggy

I've not used Promodeler in the past, and have used SRT in my last build, but Promodeler seem to come well recommended, and the details on their website are certainly 'to the point' and impressive!

Have a DS1155BLHV on the way for an ET48 2.0 bashing build so will try it out soon!!

Do you have a particular brand/make you tend to stick with??
 

Billl DeLong

Well-known member
TF Excellence Award
Build Thread Contributor
Messages
937
Reaction score
755
Location
Austin, TX
Tekno RC's
  1. EB410
  2. EB48
  3. ET48
  4. ET410
  5. MT410
  6. SCT410
Driving Style
Racer

PrimaRC

Well-known member
Build Thread Contributor
Messages
146
Reaction score
90
Location
South Coast NSW, Australia
Tekno RC's
  1. ET48
Driving Style
Basher
I have ordered one of these to try on my ET48 2.0 build https://www.agf-rc.com/35kg-high-to...ammable-brushless-servo-a81bhsw-p2972783.html I haven't used these before, but I hope it is decent. I have used various Ebay/Amazon servos with some success. The slow ones have lasted ok, but tend to break on huge jumps, the fast one's I've had either start to hunt or won't return to center correctly after a while.

I have more issues with the Nitro cars than electric cars with JX servos.
 

Klappars

Premium Member
Supporting Member
Build Thread Contributor
Messages
113
Reaction score
81
Driving Style
Basher
I run a highest DS1000 servo in my ET48.3, I have also used Savox and PowerHD in the past.

The highest servos can be bought in the UK I believe and are very high quality.

The DS1000 is extremely, extremely fast and has plenty of torque for turning Backflip LP tyres!
 

Billl DeLong

Well-known member
TF Excellence Award
Build Thread Contributor
Messages
937
Reaction score
755
Location
Austin, TX
Tekno RC's
  1. EB410
  2. EB48
  3. ET48
  4. ET410
  5. MT410
  6. SCT410
Driving Style
Racer
I have ordered one of these to try on my ET48 2.0 build https://www.agf-rc.com/35kg-high-to...ammable-brushless-servo-a81bhsw-p2972783.html I haven't used these before, but I hope it is decent. I have used various Ebay/Amazon servos with some success. The slow ones have lasted ok, but tend to break on huge jumps, the fast one's I've had either start to hunt or won't return to center correctly after a while.

I have more issues with the Nitro cars than electric cars with JX servos.

Maybe you will have better luck with AGFrc than me, but here's my experience with the brand:
 
Last edited:

PrimaRC

Well-known member
Build Thread Contributor
Messages
146
Reaction score
90
Location
South Coast NSW, Australia
Tekno RC's
  1. ET48
Driving Style
Basher
Maybe you will have better luck with AGFrc than me, but here's my experience with the brand:
Wow, ok that's a bit disappointing to read, I'll have a spare on hand then. I've only bought the one, so it might be a less painful lesson learned than your experience. What have you settled with now for 1/8th truggy? Thank you for the feedback.
 

PrimaRC

Well-known member
Build Thread Contributor
Messages
146
Reaction score
90
Location
South Coast NSW, Australia
Tekno RC's
  1. ET48
Driving Style
Basher
I have ordered one of these to try on my ET48 2.0 build https://www.agf-rc.com/35kg-high-to...ammable-brushless-servo-a81bhsw-p2972783.html I haven't used these before, but I hope it is decent. I have used various Ebay/Amazon servos with some success. The slow ones have lasted ok, but tend to break on huge jumps, the fast one's I've had either start to hunt or won't return to center correctly after a while.

I have more issues with the Nitro cars than electric cars with JX servos.
Maybe you will have better luck with AGFrc than me, but here's my experience with the brand:
I actually linked the incorrect servo above this is the one I ordered https://www.agfrc.com/index.php?id=1950 which is one of the one's you had an issue with and were advised to buy the 81 version. Oh well, I'll use it till it dies I guess.
 

Billl DeLong

Well-known member
TF Excellence Award
Build Thread Contributor
Messages
937
Reaction score
755
Location
Austin, TX
Tekno RC's
  1. EB410
  2. EB48
  3. ET48
  4. ET410
  5. MT410
  6. SCT410
Driving Style
Racer
I actually linked the incorrect servo above this is the one I ordered https://www.agfrc.com/index.php?id=1950 which is one of the one's you had an issue with and were advised to buy the 81 version. Oh well, I'll use it till it dies I guess.

Yeah that A80BHSW didn't last very long and I'm not really confident that AGFrc has been assembling any of their servos properly. I do believe that NitroPro has made a significant improvement based on the AGFrc A80BHM but they still have a few more kinks to work out around the pins and slop... I am not the only one experiencing these issues with both brands.

I would be willing to give NitroPro another chance once they have assured these issues are resolved, but I probably won't buy an AGFrc branded servo again.

I have settled on the SRT 9032 as my servo of choice for 1/8 classes :)

https://dialedhobbies.com/srt-bh9032-1-8-hv-high-torque-aluminum-case-brushless-servo-detail
 

Ifti

Well-known member
Messages
401
Reaction score
263
Location
UK
The SRT 9032 is a solid choice - and that's usually my go-to servo also.
I was drawn to the larger gear set and bearings in the Promodeller 1155 this time and thought I would give it a shot. The reviews have been very positive.....
https://www.promodeler.com/DS1155BLHV
 

PrimaRC

Well-known member
Build Thread Contributor
Messages
146
Reaction score
90
Location
South Coast NSW, Australia
Tekno RC's
  1. ET48
Driving Style
Basher
Yeah that A80BHSW didn't last very long and I'm not really confident that AGFrc has been assembling any of their servos properly. I do believe that NitroPro has made a significant improvement based on the AGFrc A80BHM but they still have a few more kinks to work out around the pins and slop... I am not the only one experiencing these issues with both brands.

I would be willing to give NitroPro another chance once they have assured these issues are resolved, but I probably won't buy an AGFrc branded servo again.

I have settled on the SRT 9032 as my servo of choice for 1/8 classes :)

https://dialedhobbies.com/srt-bh9032-1-8-hv-high-torque-aluminum-case-brushless-servo-detail
Is there anything you think I could check before installing it inside the housing? Checking for grease or the like? What about in the settings with the usb programmer?

Thanks
 

Billl DeLong

Well-known member
TF Excellence Award
Build Thread Contributor
Messages
937
Reaction score
755
Location
Austin, TX
Tekno RC's
  1. EB410
  2. EB48
  3. ET48
  4. ET410
  5. MT410
  6. SCT410
Driving Style
Racer
Is there anything you think I could check before installing it inside the housing? Checking for grease or the like? What about in the settings with the usb programmer?

Thanks

There are 5 fundamental problems with AGFrc and their re-branded servos that I am currently aware of:

1) The potentiometer is glued in place with silicone and the silicone degrades over time where the POT will slide out of place from under the main servo spline gear, I used CA glue to re-attached my POT. The symptom is when the servo no longer centers. You can either wait for issue to occur or use a better quality glue as a preventative. In a perfect world the POT should be secured with fasteners which is what I believe is done with NitroPro upgrade

2) The servo motor is also glued in place with silicone and will slide out of position which causes the pinion to slide off the motor shaft and loose mesh with the first gear in the gear box. The symptom is grinding sound where the servo may work under no load but will grind under load. This can be repaired by using a tap to reset the pinion onto the shaft. NitroPro has improved the design to where I believe they use fasteners on the motor and they include a special lip over the shaft of the motor to prevent it from sliding out of place.

3) The 1.6mm pin which aligns all the gears will tend to snap over time, NitroPro is experimenting with a softer metal to let it bend instead of snap. I have made my own pin with a body clip and that seems to be holding up better. The symptom of a snapped pin is the servo arm locks up when power is turned off. Always check that the servo arm moves freely after every run with the radio system off.

4) If the pin has snapped the servo will still function without any other warnings, but you risk bending the shaft of the servo motor because the gears will be wobbling around without the pin to keep everything aligned properly. Once you bend the shaft of the servo motor then it's damaged beyond repair... this issue exists for both AGFrc and NitroPro branded servos.

5) Slop --- After fixing the pin with a flexible body clip, then the aluminum case will start to wallow out around the slots which hold the pin and this creates excessive slop, this issue exists for both AGFrc and NitroPro branded servos and was the final reason why I switched brands of servos

I have only addressed what NitroPro has done to correct issues above the base model AGFrc servo, I did not inspect any other of the handful of rebranded servo that are also based on AGFrc servos.

I question the integrity of AGFrc but have been very impressed with all the hard work and support that is offered by NitroPro on improving the quality of AGFrc based servos, I believe NitroPro will get all these issues resolved soon :)
 
Last edited:

EvilT

Premium Member
Supporting Member
Messages
53
Reaction score
32
I have pretty much always gone with the high end Futaba’s and mainly run the CB-700 in most my builds, expensive but never let me down!
 

PrimaRC

Well-known member
Build Thread Contributor
Messages
146
Reaction score
90
Location
South Coast NSW, Australia
Tekno RC's
  1. ET48
Driving Style
Basher
There are 5 fundamental problems with AGFrc and their re-branded servos that I am currently aware of:

1) The potentiometer is glued in place with silicone and the silicone degrades over time where the POT will slide out of place from under the main servo spline gear, I used CA glue to re-attached my POT. The symptom is when the servo no longer centers. You can either wait for issue to occur or use a better quality glue as a preventative. In a perfect world the POT should be secured with fasteners which is what I believe is done with NitroPro upgrade

2) The servo motor is also glued in place with silicone and will slide out of position which causes the pinion to slide off the motor shaft and loose mesh with the first gear in the gear box. The symptom is grinding sound where the servo may work under no load but will grind under load. This can be repaired by using a tap to reset the pinion onto the shaft. NitroPro has improved the design to where I believe they use fasteners on the motor and they include a special lip over the shaft of the motor to prevent it from sliding out of place.

3) The 1.6mm pin which aligns all the gears will tend to snap over time, NitroPro is experimenting with a softer metal to let it bend instead of snap. I have made my own pin with a body clip and that seems to be holding up better. The symptom of a snapped pin is the servo arm locks up when power is turned off. Always check that the servo arm moves freely after every run with the radio system off.

4) If the pin has snapped the servo will still function without any other warnings, but you risk bending the shaft of the servo motor because the gears will be wobbling around without the pin to keep everything aligned properly. Once you bend the shaft of the servo motor then it's damaged beyond repair... this issue exists for both AGFrc and NitroPro branded servos.

5) Slop --- After fixing the pin with a flexible body clip, then the aluminum case will start to wallow out around the slots which hold the pin and this creates excessive slop, this issue exists for both AGFrc and NitroPro branded servos and was the final reason why I switched brands of servos

I have only addressed what NitroPro has done to correct issues above the base model AGFrc servo, I did not inspect any other of the handful of rebranded servo that are also based on AGFrc servos.

I question the integrity of AGFrc but have been very impressed with all the hard work and support that is offered by NitroPro on improving the quality of AGFrc based servos, I believe NitroPro will get all these issues resolved soon :)
wow @Billl DeLong that is a very extensive write up, thank you for your thorough response. I will probably just run this thing till it dies and chalk this up to experience. I have a couple of spare 35kg Ebay specials that I will have on hand as spares. Hopefully this will get me by for a few months at least. Servos have been such a painful part of the hobby for me and I know that it is frustrating for many. In hindsight if I knew that there was a servo that would be reliable I'd be willing to spend the money, because the amount I've spent on rubbish would well and truly cover the cost.
 

Billl DeLong

Well-known member
TF Excellence Award
Build Thread Contributor
Messages
937
Reaction score
755
Location
Austin, TX
Tekno RC's
  1. EB410
  2. EB48
  3. ET48
  4. ET410
  5. MT410
  6. SCT410
Driving Style
Racer
I knew better... I got suckered into AGFrc with a low introductory price of $45 and then I foolishly spent $80 on subsequent servos where the servos will probably do just fine for light duty bashing with small jumps which is why their servos were fine in my 1/10 cars raced on smaller 1/10 tracks.

AGFrc servos are not designed to handle the rigors of racing on a 1/8 track with large triples.... too many hard chassis slaps will cause the internals to unglue themselves, etc...

SRT servos are very reputable and are available for a reasonable price ;)
 

Billl DeLong

Well-known member
TF Excellence Award
Build Thread Contributor
Messages
937
Reaction score
755
Location
Austin, TX
Tekno RC's
  1. EB410
  2. EB48
  3. ET48
  4. ET410
  5. MT410
  6. SCT410
Driving Style
Racer
I wish I read this 2 days ago. I ordered and AGFRC A81BHM: https://www.agfrc.com/index.php?id=2111 I hope it holds up.

Everyone at the club in my area 5+ drivers have experienced a 100% fail rate of every single AGFrc servo where most tend to fail between 10-15 race days, one guy snapped a pin on the very first battery pack, ha!

If you're lightly bashing around on the street, then chances are you'll do fine, but if you're doing large triples on a 1/8 track with big air, then I wouldn't waste your time with AGFrc, try to sell it as new to some other sucker, ha!
 
Messages
19
Reaction score
6
Tekno RC's
  1. NB-48
Driving Style
Basher
I run a Protek 155-S and a Futaba S3004 in my NB48 2.0, respectively for steering and throttle/brake duties. No problems out of either of them. Generally don't even give the time of day to these off-brand servos; there's no telling what you get and there's no chance they're even attemping to come close to their ratings.

I look at Futaba, Hitec, Savox, ProtekRC, and if I don't find what I need there I find the closest match from there. I'd rather have a servo that's skookum as frig but a bit slower than a servo that claims to be snappy as can be and lasts a few tanks at most. Maybe that's because I fly planes more than I drive cars but I just don't trust off-brand servos any farther than I can throw them.

I've also found that people often WAY over-estimate how much servo they need. Even Tekno themselves. In no world do you need >300oz/in to stop an NB48 2.0; my measly little 55oz/in S3004 is able to get it to lock up the tires and skid on command! And open a carb barrel? Any half-decent 9gram servo could open a carb up. The only thing using a 300oz/in servo in this position accomplishes is make the builder spend more money than necessary to get their car set up. I will admit I would like a bit more snappiness to my throttle and brake so I may swap it out with a Savox 1251MG in the near future, but for now I'm all too happy to drive it on what's basically the cheapest quality servo you can put in the car.

Truth be told I'm suspecting you don't even need 300+ oz/in to steer the thing either, but as long as my 155-S chooches happily I will leave it there. I run half as much torque steering my Mad Crusher GP which puts way more demand on its steering servo and have no problems with that rig.
 
Last edited:

HigginsJD

New member
Messages
3
Reaction score
0
Everyone at the club in my area 5+ drivers have experienced a 100% fail rate of every single AGFrc servo where most tend to fail between 10-15 race days, one guy snapped a pin on the very first battery pack, ha!

If you're lightly bashing around on the street, then chances are you'll do fine, but if you're doing large triples on a 1/8 track with big air, then I wouldn't waste your time with AGFrc, try to sell it as new to some other sucker, ha!
I ordered your goto from your favorite vendor. You should get referral bonuses.
 

PrimaRC

Well-known member
Build Thread Contributor
Messages
146
Reaction score
90
Location
South Coast NSW, Australia
Tekno RC's
  1. ET48
Driving Style
Basher
Interesting article here with the EB48 2.0 : https://www.promodeler.com/caseSTUDY/Servo-for-a-comp-buggy

I've not used Promodeler in the past, and have used SRT in my last build, but Promodeler seem to come well recommended, and the details on their website are certainly 'to the point' and impressive!

Have a DS1155BLHV on the way for an ET48 2.0 bashing build so will try it out soon!!

Do you have a particular brand/make you tend to stick with??
Hi mate how have you been finding the Promodeler servo? Any feedback you can give us?

Thanks
 

Ifti

Well-known member
Messages
401
Reaction score
263
Location
UK
Hi mate how have you been finding the Promodeler servo? Any feedback you can give us?

Thanks

No issues at all. Im running via the XR8 Plus BEC output at 7.4v and its solid, no need to go to 8.4v at all. A beast of a servo! As soon as I installed I found no need to set end points etc at all - just seemed spot on. No servo whine etc whatsoever. Turns with authority at standstill on any type of surface (tested on grass too) - see no need to run at the higher voltage, it's more than enough - maybe even a little overpowered.
Bear in mind this was for my basher, I haven't a track near me to race, so not sure on longevity etc just yet, but so far its my new favourite (along with the SRT9032).
 

Similar threads

Recent Popular Liked

Top