|KST DS125MG Servo Specifications|
|Dimensions||30 mm wide x 10 mm thick x 35.5 mm high|
|Stall torque (4.8V)||6.0 Kg.cm||83 oz in|
|Stall torque (6V)||7.0 Kg.cm||97 oz in|
|Operating speed (4.8V)||0.15 sec/60°|
|Operating speed (6V)||0.12 sec/60°|
|Operating voltage||4.5V to 6.0V|
|Lead length||16 cm||6.3 in|
|Weight||27.5 g||0.97 oz|
|Bearings||Dual ball bearings|
|Motor Type||DC motor|
|Supplied accessories||3 white plastic output arms, 3 red extra strong plastic output arms, 2 output arm retaining screws, 3 mounting screws|
|Optional accessories||Frame with bearing for the KST X10, Ply Frame for KST X10, KST Plastic Servo Arm Set, KST 25T-5 Metal Servo Output Arm, Gear Set for KST X10|
Review by: Bill T, Burnie Tasmania
Before going further I should state that I am delighted with these servos and Neil's service. The servos have minimal backlash, good speed and centering, and under normal conditions are extremely reliable. However, like any mechanism they have limits.
I fly mostly on slope and the normal heavy usage that this entails coupled with my inexperience with heavy, slippery planes has given these servos an extreme trial and revealed the conditions under which they could fail.
When I bought my first moulded glider, a second hand but immaculate Valenta Prosecco full carbon it was fitted with these servos on the ailerons, and I also installed on the flaps before I flew the model.
First flight I had a hard dorked landing in turbulence and damaged the fuselage but no apparent damage to servos.
On rebuild I installed a motor to get some landing practice away from slope and had many successful flights but with the inevitable failures to fully raise flaps on landing.
One day I noticed that the flaps servos although operating correctly had some notchy movement at certain points in their travel. I decided to investigate and discovered that both of the servos had missing teeth on their output gears. Purchased replacement gears from Neil and servos functioned perfectly after they were fitted (see my review of replacement gearsets).
Later a combination of gusty weather and over confidence led to a vertical arrival at high speed. Luckily the ground was soft but still the carbon wing joiner was cleanly sheared off both sides. Miraculously the only other damage apparent was a couple of very minor cracks in one wing and the tail broken off - a tribute to the massive construction of the Prosecco. However further inspection revealed that the plastic flap servo arms had shattered and the servos had rough spots in travel, aileron servos seemed OK initially but careful inspection also showed rough spots. All of the servos had broken teeth. Since rebuild of plane and servos I have had many more flights with absolutely no issues.
Given the hard usage detailed above it is no surprise that the gear failures occurred. The output gears are robustly dimensioned and are used on a wide range of KST servos up to 10kg.cm torque. However they are made from case hardened steel and large impact loadings cause brittle failure of teeth. To some extent this is a good thing as it protects the other parts of the mechanism from damage, after rebuild all the servos have shown no ill effects over a long period.
Usually the failure is of a single tooth and can be quite difficult to detect. It is very good practice to carefully inspect the servo operation after any hard landing or flap contact, and dismantle and check the gears if there is any suspicion of damage.
Again I must state that I am completely satisfied with these servos and have no hesitation in recommending them.
Review by: Wayne JonesKST DS125MG
Always been great servos and add to that great service from Hyperflight.
Delivered to Australia in under 2 weeks.
Review by: Eric ElstonKST DS125MG
These servos buzz a fair amount as they hunt for neutral point. Otherwise they seem to be great so far
Review by: Mezri FILALIPrecise
Very pricise and no play around neutral.
Review by: Gary GrantKST DS125MG
Great Servo and hyper flight is a great online store!
Review by: John Lacey
Excellent servos . Cant fault them in any way and quickly despatched.
Review by: Jolly Roger
I donít like this servo....I LOVE IT! Well built, no discernible slop, strong and light...just right for the key role of elevator servo in my 4m 5kg glider. The only difficulty is believing that a servo this good can be so cheap. Assuming it proves reliable, this is remarkable value for money.
Neilís service first class as always, and nice to see a reasonable p&p charge. Many thanks.
Review by: Pete WReliable High Performance Servoi
I have all my gliders fitted out with these servos and they have been in use for many years. They are a good high perform high quality servos that have never let me down. Highly recommended
Review by: Gabriele
Work fine as elevator on discus 4,5m
Review by: Good Value servos
Very precise servo equal to much more expensive servos.Prompt service.
Review by: Richard EdmundsGOOD SERVOS
Have been using these for several years, and have never had one fail. Brilliant value and Neil's service is always 1st rate
Review by: Shaunthin wing servos
Excellent product great value for money center perfect every time and no slop
Review by: Kevin JohnsonKST DS125MG Wing Servo†
Super fast service as usual from hyperflight. Bought 4 of these for a Greacalis 3m glider
The servos are quality servos. No slop. Well made. Good centering
Strong and reliable
Review by: Barry Hallgreat Servo from Hyperflight
Product is as ordered and arrived within good time. Very accurate and powerful & good response & centering
Review by: Anonymous
Review by: Anonymous
Used in my 5 mtre vortex good value and performance will definatly use again
Review by: ian bryant
servos look good, nice smooth operation, very fast delivery,,,pleased
Review by: Steve RogersKST DS125mg wing servo
An excellant servo at an amazing price, bought to replace a damaged similar servo in an older non HV model. Usual top class service from Neil that we are so familiar with.
Review by: Pete
Great performing servo at a competitive price
Review by: Colin Taylor
KST DS 125 Great servo man enough for the ailerons and airbrake in a 5mtre woodie glider, no gear box slop. Great service
Review by: PW
Good quality reliable servo at an affordable price backed up by a great service.
Review by: Richard Edmunds
These servos are an excellent combination of performance and quality.
Very reliable service from Neil
Review by: Jcc
Utilisť comme servo de volets sur Xplorer 3, fonctionnement impecable.
Review by: PW
This is the second batch of 4 KST DS125MG Wing Servos I have bought from Hyperflight which I intend to use in my Valenta models Freddy. I am very please with the performance of the DS125MG servos that I installed in my Schwing last month. I intend to use the KST DS125MG Wing Servos as my preferred wing servos. Good performing servos at a reasonable price.
Review by: Nicholas PuseyKST DS125MG
I bought 4 of these off Neil for my Nan models Orion and wow, value for money, amazing!
Brilliant servos, powerful, no slop and very efficient.
They fly my machine around like nothing else I have had before.
Review by: PWKST DS125MG Wing Servo
I recently bought a 2.3m Schwing. My standard wing servo choice for such a model would be a Hitec 125mg however I decided this time to look for something with a higher torque and faster movement for the Schwing. Looking at the data of the KST DS125MG wing servo it was similar in size and the speed was 0.02 seconds faster than the Hitec 125 servo. However the torque was double that of the Hitec 125. At on £1 extra the decision was made and I ordered 4 from KTS 125's with the servo frame and bearing kit from Neil. Receiving the usual excellent service from the Hyperflight team the ordered arrived 36hr later (it was a Sunday when I ordered). The servos are very well made and operate precisely. They were easy to install into the wing using the frame bearing kit which will allow my to remove the servos for repair or replacement even on the slope. I have yet to complete the fuselage on the model and fly it but I am very happy with the servos during installation and bench testing. Over all great performance and value.
Review by: Andy DeaconTough little servo
Seems to be a very high quality servo with plenty of power in a compact sturdy case
Review by: Ken Rose
very nicely made and for it's size to be able to handle 7.0Kg is fantastic.
Review by: Malcolm Tyenew zefiros
Really nice servos, the only criticism I have is that the metal
servo arms were rather loose on the splines. I cured this by
carefully squeezing the outside of the splined bosses with a
large drill chuck, worked really well but sounds brutal!
I would certainly use these servos again in future.
Review by: Richard EdmundsASW17
Overall well made with powerful torque without compromising speed. Slight play in one servo, and had to get Neil to send me another aluminium arm, as the one supplied was burred.
As always, great service.
Review by: John TunnicliffeSolid servos
Fitted to my 2.75m Floater as a strong wing servo only 5 hours air time as yet but good tight and reasonably fast servos. Time will tell. As an aside, just gone over 120hours fly time on my Mini Graphite the SD100 tail servos are still going strong!
Review by: AnonymousBargain substitute for MKS
I bought this to replace an MKS DS6125 mini servo that had developed oscillation. The MKS was being used as a flap servo on a 4 servo wing and the oscillation seemed to be as a result of a tiny amount of play that had developed in the gears. The KST dropped straight into the servo frame and seems to be equally good as the MKS it replaced.
Review by: David Martinkst flap servo
Nice powerful servo and at reasonable cost happy to be fitting them into my LET Ventus cx 6mtr
Review by: AnonymousKST DS125MG Servo
A really good servo. Well made with good centering and resolution. Be careful that all linkages are free for their full travel and do not bind as I have managed through my own fault to burn a motor out (the motor brushes are very delicate).
Review by: Anonymous
These are good, they are accurate, powerful and well built to stand the stresses of a larger model on the slope, this means I will have to buy more, couldn't bear to use anything less in my mouldie.
Review by: Anonymous
So far the KST DS125MG wing servo's have performed perfectly, they are fitted to a new Maxa4e.
Review by: Anonymous
Have not yet had chance to use this servo type but recently purchased 8 of them for an upcoming project.
I have however found that there are considerable differences in the amount of play in the gear train from one servo to the next. I had to send back 5 out of 8.
Excellent response from hyperflight in changing the servos for slop free ones.