View Full Version : Trex 500 Collective Servos... Which ones...

01-13-2009, 06:05 AM
Hi All... I'm currently looking into collective servos for my trex500... max Price allowed is around $50-60 each...

currently I've been pondering....

hs 225mg
hs 5245mg

My buddy flys extreemly well on the 225mg's and suggests for me to use them also... but.... When I had them on a 48" balsa 3d plane I found them to be very weak for my rudder, and they didn't center very well (ALL4)... I know that they should hold up for a 500heli, but has anyone else found that they don't center well?

If you have any opinions on other brands I am willing to hear any options... I would also Prefer Metal gear servos....

I will be using a 9254 servo on the rudder and a Spartan DS760 gyro....


01-13-2009, 06:25 AM
I am currently running the Hitech HS-5245mg's in my T-Rex 500. I bought them hoping they would be as tough as the HS-65mg's in my 450. The 5245s work well in the 500. I have a flying buddy that also runs them in his 500. One minor problem with them is how they fit in the frame. The 500 frame was designed to fit Futaba S9650s. You will need to use the included spacers to run the 5245s. No big deal really but some don't like using the spacers. The only other downside to them is that the servo case is weak. In a crash you will not strip your gears but you will likely break the top of the servo case. The problem is where the pin for the gears mates with the top of the case. The case is not strong enough and the pin cracks the case. The last time I crashed I had to look high and low to get three new servo cases before I could fly again. If I was building one over again I would use Futaba S9650's. You might also look into the new Align DS510 servos that come in the 500esp kit.

I just built a 425mm blade MSH Protos about a week ago. The 5245s will fit in it as well, but I used Futaba S9650s on it and just plan on replacing gears when I crash. I got all three of them from ReadyHeli.com for $160 shipped.

You might want to check out the Protos. It uses the same 425mm blades and 6s 2500 packs as the 500. However, my Protos weighs in 290g lighter than my T-Rex 500. Here is a link to their website.



The 9254 is going to be rather large on the tail of the 500. If you want to use that servo you will need the rudder mount that comes with the T-Rex 600 kit. I am using a Futaba S9257 for the rudder on both my 500 and Protos. I have it hooked up to a Gy401 on the 500 and a Spartan DS760 on the Protos.

For batteries, I am really like the Outrage 25C 6S 2500 packs. They really put out the power! I have 4 that I share between my 500 and Protos. I get them from Kyle at RCSuperSales.net for $128 shipped.

Hope this helps,


01-13-2009, 06:47 AM
Speed and tork are less on the 9650's so that rules them out.... No sense for me to pay more, get less, and have the gears strip...

any better options...


01-13-2009, 06:55 AM

I'm also looking at the MKS servos... they spec much nicer than the rest... anyone use them? they seem to get good reviews on runryder...


01-13-2009, 07:23 AM
appears these can be a Gearset upgrade for the 9650...
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=6757&Product_Name=MKS_DS9660_Precise_Digital_Servo_Gear _Set


01-13-2009, 08:15 AM
I just bought a set of the DS9660's I'll let you know how they work out...


01-15-2009, 05:36 PM
Those look like they will work great! Let us know how they turn out. I have seen the gear sets before and am planning on using them in my 9650's if and when they strip out. The DS9660 look to be .01 faster than the 9650s on 6V and have the same stall torque. According to the specs posted on servo city.

The big plus is that they come with metal gears.

Hope they work out for you.


01-15-2009, 09:04 PM
there are a few reviews on helifreak, and runryder, and a few other places... most people seem to really like them... I should get them soon, they're already in customs Inspection on the tracking number...LOL


01-25-2009, 07:10 AM
Hi, I thought I'd let you know that we finally finished building my Trex500... the servos seem good, I won't know more untill We do a test flight....

also... I'm using a zippy 3300mah pack in my trex, I had to lower the battery tray about 9mm down, but it fits perfect, and strangly enough... it balances out perfect...

Trex specs...

MKS 9660 servos for cyclic,
futaba 9254 servo for tail
Spartan 760 gyro - With Bert krammer settings... (and newest firmware)
zippy 3300mah 6cell pack (529grams)

another tip, for washers for the trex servo mounting, you can use frame washers.. they look great and hold great too...

side note....
funny thing happened... My buddy built the tail wrong, the blade grips were backwards.... so when we went to throttle up, after a little rpm's... it would spin counter clockwise like mad.... He thought it was the belt being twisted... but I wasn't so sure... so I did a google search and found someone on rcg asking about the same thing.... and they posted that the blade grips were backwards... so I checked mine and compaired them with his... and What do ya know... they were.... so we put them back and it hovered fine.... Trims were within a click or two right of the get go.... looks to be a good day when the rain lets up....


03-17-2009, 08:15 PM
did anyone mention the JR3517MG? from what i can tell its a great servo. 0.9sec and 51 oz.in @6v... not too bad...