Published January 13th, 2007 by Jim O'Halloran
Hyper 7 Steering Servo
Kevin left a comment on one of my earlier posts about running in the Hyper 7, saying that he’d broken the steering servo in his and no one seems to stock Ho Bao servos. I had the same problem with mine, I stripped out the steering servo pretty early on after landing awkwardly off a jump. Anyway, I replied to Kevin’s comment in email, but thought I’d share my replay in case it helps anyone else…
In general terms servo’s (as used in cars anyway) come in two sizes. Standard and Mini. The mini servos are generally only used in smaller scale cars, like 1/12th and 1/18th scale. The Hyper 7 servo’s are standard size.
The other thing to look out for is the type of plug which goes into the receiver. Generally these are either a “Futaba” sttle which have a small tag on one end to stop you from plugging it in backwards, or “Sanwa” which doesn’t have a tag and instead has two chamfered corners. If you’re careful you can plug a Sanwa plug into a Futaba socket but there’s nothing to stop you from plugging it in the wrong way. Likewise, you can take to a Futaba plug with a knife and cut it to fit a Sanwa socket, I’ve done that myself and it works fine, but its really just easier to get the right plug.
The standard Ho Bao receiver has a Sanwa plug. In fact, I think the whole radio is just a re-badged Futaba unit, in which case, the servo’s that came with the car would most likely be rebarged Futaba S3001’s. According to Futaba’s web site they do sell gear sets for the servos, but given that you can buy the whole servo from most happy shops for around $30-$35 it may not be worth trying to fix. You don’t have to use Futaba servo’s either, any standard size servo with a Futaba plug would work fine. That said, the Hyper 7 is a heavy car and the plastic gears break pretty easily, so I wouldn’t replace it with cheap servo. You’ll break them too quickly and it’ll cost you more in the long run.
I replaced mine with a high speed, metal geared servo (Hitec 525MG). The high speed gives a bit quicker steering response, but the metal gears make the servo much more durable. Mine’s still going strong after 12 months. The only problem I had is the Hitec servo is a different size where the servo horn connects to the sero so you’ll need to adapt one of the servo horns that comes with the Hitec to fit rather then using the standard one.