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Manufacturing and Marketing R/C helicopters since 1987

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Product Questions

Q. At full power, why does my RC helicopter not come off the ground?

A. Pitch may not be set properly, (on nitro RC helicopters) the engine may be set too lean or too rich or not enough RPMs [top]

Q. Why are the gears so tight on my helicopter?

P. When I try to turn my main gear, all the gears seem to be very tight, making it difficult to turn them by hand. Alternately, when I have changed my main gear, it again is difficult to turn the main gear in the helcopter.

A. Century uses a proven, dual gear reduction mechanism to deliver power from the engine to the main rotor head. When the helicopter is new, it is normal for the drive gears to be tight. Just wait for 4-6 tanks of fuel while the engine is wearing in to have the gears become silky smooth. Unlike most of the other designs in the market, where there are only two gears, the clutch bell and the main gear, our helicopter has four. The key benefit with this type of design is to reduce the loading on the individual teeth of each gear as there are more teeth engaged at all times.

Be carefull if you have changed the clutch bell, and installed a new lining by bonding it into the clutch bell with JB Weld. If the amount of adhesive is excessive the gap between the clutch and the bell will be too small. Use only a small amount and spread evenly on the liner. [top]

Q. Why does my counter gear seem to be warped?

P. When I spin the main gear the counter gear wobbles up and down.

A. This has been a question that customers have asked from the RC helicopters we release back in 1997. The short answer is, when the assembly instructions are followed and the counter gear assembly has no vertical play (by pressing on top of the metal drive gear and the shaft under the counter gear) the counter gear will have a high spot when turned and viewed from the side. This will not affect how the helicopter performs and will not contribute any additional vibration.

Even in the situation when the counter gear has a slight amount of vertical play, customers have flown their helicopters for years without incident. In step #10 of the Hawk IV manual, we very carefully walk you through the best procedure when building your helicopter. In the case when you have purchased the ARF assembled versions, we recommend that you check this before hand and adjust it if the gear wobbles excessively.

When the counter gear is sighted from underneath, when the mechanics are disassembled, you will notice that the gear turns perfectly true. There is zero lateral movement (the gear spins without moving in a left-right or forward-backward direction) which means that the more critical gear mesh is maintained the same and the gears will wear in normally. [top]