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HPI - steering problem - servo upgrade help

HPI - steering problem - servo upgrade help

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Old 11-08-2017, 07:54 PM
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Questions?? HPI - steering problem - servo upgrade help

Hello, I've been upgrading my HPI Sport 2 Sprint trying to make it go straight, there was some floppiness on the steering system, I upgraded the front ball cups now it feels pretty steady but still steers so I finally spotted the problem:

The front servo is not powerful enough to keep the steering system straight, so after the turns it doesn't return to dead center so it keeps having a curved course. Also in case there's little force on the road (little rock, bump or sth) it again steers on its own making it super hard to drive especially in tighter situations.

After some tests even lifted in the air I'm pretty convinced it's the stock servo. I looked on ebay and youtube and there are some good ones but pretty expensive (around 50$) can you suggest a budget solution? If there's one...

For e.g. is this worth it or I have to go with the expensive ones? Any experiences?
ebay.com/itm/Core-RC-9016MG-Servo-9Kg-16-Sec-CR494/371847535431?epid=1941984865&hash=item5693d71b47:g :wnEAAOSw241Yh2zV

Waiting for your comments. Thank you :-)
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Old 11-08-2017, 09:07 PM
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Hard to say without knowing what is currently installed, but I would look at something like the Savox 1251MG ( and $50 is not an expensive servo to most BTW ). If you really want to go with a less expensive servo - copy the dimensions and torque specs of the Savox.

I would avoid super cheap ..... after all, isn't that what you have now?
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Old 11-08-2017, 10:04 PM
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Originally Posted by belewis01 View Post
Hard to say without knowing what is currently installed, but I would look at something like the Savox 1251MG ( and $50 is not an expensive servo to most BTW ). If you really want to go with a less expensive servo - copy the dimensions and torque specs of the Savox.

I would avoid super cheap ..... after all, isn't that what you have now?
I'm on the stock right now: ebay.com/itm/HPI-1-10-Jumpshot-MT-SF-10W-HIGH-TORQUE-WATERPROOF-SERVO-Steering-Throttle/371498428709?hash=item567f082925:g:9pIAAOSwO7haAcp H

I must say that I don't quite understand the specs and what the numbers mean except from the dimentions and delay time.

It's cheap but branded (cheap & branded usually means bad quality - higher life). Even on this cheap servo the kg/cm torque seems much higher than my stock and(!!!) the 50$ savox servos

Cheap: ebay.com/itm/Power-HD-4-8-6-6V-Super-Torque-Digital-Servo-Crawler-Buggy-1-10-RC-Car-LF-20MG/311773799105?epid=509801116&hash=item48972aa2c1:g: 21cAAOSwHsRYDaAI
Savox: vi.vipr.ebaydesc.com/ws/eBayISAPI.dll?ViewItemDescV4&item=131567247601&t=1 497235778000&tid=10&category=56615&seller=rcmart&e xcSoj=1&excTrk=1&lsite=0&ittenable=false&domain=eb ay.com&descgauge=1&cspheader=1&oneClk=1&secureDesc =0
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Old 11-08-2017, 10:17 PM
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I like savox servos, even the cheaper (sub 40 dollar) ones are good.

this is essentially a savox copy https://hobbyking.com/en_us/turnigy-...5kg-10sec.html

and is cheap as well.
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Old 11-09-2017, 03:33 AM
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Originally Posted by ThePanda View Post
this is essentially a savox copy hobbyking.com/en_us/turnigy-1258tg-digital-titanium-gear-servo-57g-13-5kg-10sec.html
and is cheap as well.
I found this one, same brand similar performance and availability. What is the operating voltage 4.8 and 6? Is this selectable on the car?
ebay.co.uk/itm/Turnigy-AN13-all-purpose-Metal-Gear-Servo-14-5kg-cm-0-13s-fits-1-10-steering-HPI/322263310924?epid=2197068882&hash=item4b0863e24c:g :Ha8AAOSwmfhX20O3
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Old 11-09-2017, 10:52 AM
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Originally Posted by Bob Corey View Post
I'm on the stock right now: ebay.com/itm/HPI-1-10-Jumpshot-MT-SF-10W-HIGH-TORQUE-WATERPROOF-SERVO-Steering-Throttle/371498428709?hash=item567f082925:g:9pIAAOSwO7haAcp H

I must say that I don't quite understand the specs and what the numbers mean except from the dimentions and delay time.
So, the stock servo is called High Torque, but it has about 1/2 the torque of the Savox 1251 ...... I can see why you have a problem.( Savox 1251 is kind of a standard go to servo for 1/10 scale on and off road ). Look for a servo, with similar dimensions to your stock servo so it will fit in your car. Look for a torque number around 7-9 kg.

4.8V or 6V is typically set by your ESC program. Setting is dependent on what voltage your receiver can handle, so if you have a manual, check there. Most radios and servos for the past 10 - 15 years have been able to run at 6V and you would see improved speed and power from your servos.

The HobbyKing servos would be OK, at least you know they are a copy of name brand servos. I've heard the Power HD is OK too.
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Old 11-09-2017, 09:01 PM
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Power HD 1501. You can get it from valuehobby.com for $12. I've used dozens of these. They are very good, decent speed, moderate torque, low budget servos. They won't perform as well as the Savox 1251MG but you could buy 4 of these for less than one Savox.
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