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Old 10-27-2008, 04:43 PM
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kavvika kavvika is offline
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An in-depth look at Recoil servo options:

On-center spacing:
Both straight mounts: 43mm
Left offset mount, right straight mount: 37mm
Left straight mount, right offset mount: 33.5mm
Both offset mounts: 26mm
The Pro does not come with screws to mount the servo to the servo mounts, the servo mounts to the chassis, or the servo saver to the servo output shaft. You will need 3mm diameter countersunk screws to attach the mounts to the chassis and 3mm panhead screws with washers to securely attach the servo to the mounts, and the proper screw to attach the servo saver depending on which servo you choose.

The typical BEC provides 5v for the servos, so the speed and torque numbers are the measurements at 4.8v. This is the minimum guaranteed performance. A digital servo can only be used with a radio that offers EPA adjustment. A coreless motor is preferred over a ferrite motor as it spins up faster. If a servo is not listed as having a coreless motor, that means it has a standard 3-pole ferrite motor.

*List now arranged by price: lowest to highest*

Hitec HS-81
Standard micro servo for mini cars and aircraft
Street price: $15
Analog or digital: Analog
Ball bearings? No
Metal gears? No
29mm length, 33.27mm on-center mounting tabs. Use left straight mount, right offset mount
.11 sec/60° 36oz-in torque at 4.8v
User comments: Might as well pick one of these up for a spare! Very quick, more than enough torque. No ball bearings or metal gears, but what did you expect for $15? Hitec used to sell a metal-geared version of this servo called the 81MG, but I believe it was discontinued and replaced by the 82MG. Not sure how the HS-85 fits into their lineup, though. The Multiplex Tiny S is a clone of this servo. Fitment confirmed by RCTech user "johnnyshore."

Hitec HS-65MG
Micro servo for mini cars and aircraft
Street price: $36
Analog or digital: Analog
Ball bearings? Yes, 1 on output shaft
Metal gears? Yes
24mm length, 27mm on-center mounting tabs. Use both offset mounts
.14 sec/60° 25oz-in torque at 4.8v
User comments: Hitec also offers a Karbonite-geared version of this servo, the HS-65HB, for $26. I remember reading that some people had trouble attaching the RC18T servo saver to the MG version of this servo. The servo is not sold with the proper screw, which is 2.5 or 2.6mm in diameter. The 65HB would be a great budget upgrade servo. Fitment confirmed by RCTech user "lutach," who uses it with the Associated "Hitec" RC18 servo saver.

Blue Bird BMS-385DMAX
Micro servo for mini car and aircraft
Street price: $40
Analog or digital: Digital
Ball bearings? Yes
Metal gears? Yes
26mm length, use left straight mount and right offset mount.
.15 sec/60° 57oz-in torque at 4.8v
User comments: Huge torque in a small package. Hard to go wrong at this price point. However, I have only heard of one instance of this servo being used in a Recoil. Blue Bird also offers a non-digital version of this servo named the BMS-380MAX, along with a nylon geared BMS-380 and metal geared (no ball bearing) BMS-380MG for $24, $15 and $17, respectively. While you're checking out the Blue Bird servos, be sure to consider the BMS-373 and BMS-375 (digital) series, also. They're 22mm long servos that compete with JR's DS285MG. There's simply too many to list, so check their website.

JR DS-285MG
Sub-micro servo for mini aircraft and car
Street price: $50
Analog or digital: Digital
Ball bearings? No
Metal gears? Yes
22mm length. Use both offset servo mounts
.18 sec/60° and 17 oz-in torque at 4.8v
User comments: A lightweight option at only .42 oz. Speed does seem a bit slow for tight, twisty indoor tracks. Must buy new, I have never seen one for sale secondhand. A nylon gear version is available, the JR DS285, for $35. Fitment confirmed by YM user "Nerve."

Multiplex Polo Digi 4
Mini servo for aircraft and cars
Street price: $50
Analog or digital? Digital
Ball bearings? Yes, 2
Metal gears? Yes
28mm length. Use left straight, right offset mount.
.10 sec/60° 39oz-in torque at 4.8v
User comments: The fastest servo I have seem, and quite a bit of torque, which is surprising considering it uses a 3-pole ferrite motor. Price is good for its awesome specs. Must buy new, I have never seen one for sale secondhand. Recommended by RCTech member "duneland," fitment not yet confirmed, but I believe it will drop right in.

Airtronics 94761Z
Mini servo for sailpane wings, T-rex tail, and 1/18 cars
Street price: $60
Analog or digital? Digital
Ball bearings? Yes, 2
Metal gears? No
27mm length.
.15 sec/60° 55oz-in torque at 4.8v
User comments: Recommended and fitment confirmed by RCTech member "duneland." Which mounts to use is currently unknown, but I'd guess the left straight mount and right offset mount.

Futaba S-9650
1/12 scale pan car or aircraft servo
Street price: $60 Used price: <$35
Analog or digital: Digital
Coreless motor
Ball bearings?
Metal gears? No
35.5mm length, 43mm on-center mounting tabs. Use straight mounts.
.14 sec/60° and 50oz-in torque @4.8v
User comments: Like the S-9602, the 4 additional mounting tabs will need to be clipped off. 50% more torque at the expense of speed. Would be a good servo for a off-road truck, but between this and the S-9602, the latter is probably a better choice. Fitment confirmed by RCTech users "supafastsupra2" and "geeunit1014."

Futaba S-9602
1/12 scale pan car or aircraft servo
Street price: $65 Used price: <$40
Analog or Digital: Analog
Coreless motor
Ball Bearings? Yes, 2 on output shaft
Metal Gears? Yes
36mm length, 44mm on-center mounting tabs. Use straight mounts.
.11 sec/60° and 30 oz-in torque @ 4.8v
User comments: A very tight fit in the Recoil. Servo lead wire exits at a sharp angle due to front bulkhead. The four additional servo case mounting tabs must be clipped off. Since output shaft is closer to centerline of car, bellcrank linkage needs to be shortened for proper steering. Metal gears and ball bearings are a huge plus, since movement is smoother and a stronger servo saver can be used, but it is one of the heaviest options at 1.1oz. Fitment confirmed by me, "Kavvika."

JR Z3650
1/12 scale pan car servo
Street price: $90
Analog or digital? Digital
Coreless motor
Ball bearings? Yes, 1
Metal gears? Yes
33mm length
.11 sec/60° 42oz-in torque at 4.8v
User comments: The quickest, torquiest 1/12 scale servo with metal gears you can put in a Recoil, but it comes at a steep price. At 1.04oz, it's second heaviest to the Futaba S9602. Highly recommended by RCTech member "duneland" and fitment confirmed by "ammdrew."
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Last edited by kavvika; 10-29-2008 at 03:19 AM.
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