EasyCounter
I have assembled over a dozen JR Ergos. Basically, the Ergo is very easy to assemble and maintain. While assembling the Ergo, there are points below that you should be careful of from my experience:
Line up the frame squarely- Don't screw tight all the frame bolts when you are assembling the frames. After you've had the whole frame structure built up, put the whole frame, leave out the L-shaped landing gear mount, onto a piece of glass. First, try touch the four corners of the frame to see if it rocks, and if it does, loosen all bolts and use your hand to lightly press on the top of the frame while you re-tightened the bolts. Next, if you have a 90 degree ruler, set the ruler onto the frame and the glass to see if the frame is 90 degree perpendicular to the glass. This is very important, cause if your frame is not set right, the heli will vibrate or will not fly straight. After the frame is set straight, loose each bolt and apply locktite and re-tighten one by one. This is very time consuming, but contributes to the stability of the helicopter.
Before you slot the top portion of the clutch pinion into the starter bearing block, put some locktite onto inner surface of the lower bearing. This will stick the pinion with the bearing. If you do not do this, the top of the motor pinion will wear out after prolong use, and leads to vibration and damage of gears. When applying loctite, be careful not to let the locktite goes into the bearings, or the bearings will be damaged.
Due to the design of the fan hub, the engine locknut might come loose during flight, and if it does, it will jam the clutch, and the whole rotor will stop. Imagine having your heli's rotor stopped during a flight! I have seen this happened to some people, and this tip is derived from other people's disasters. As a result, while tightening the fan onto the engine, be sure to use just a drop of loctite, and tight the prop nut real tight. I use a stainless steel 6mm spring shim to prevent the prop nut from coming loose, but it might be hard to find one of these washers.
While mounting the engine, make sure that the clutch is 90 degree to the start shaft. You can check this by rotating the clutch bell and see if it touch on the clutch after assembling the engine. When setting the engine into the heli, line up the clutch so that the bottom of the clutch sticks out of the bottom of the clutch bell about 1mm. Don't go overboard and push the engine all the way up to the clutch bell, cause it will increase wear of the clutch liner.
While setting the pitch servo, going by the manual will only give you about 13 degree of pitch travel. If you would like a bigger range, use a longer servo arm. While assembling the cyclic, collective, pitch servo, make sure they are 90 degree to the pushrods, the three mixing arms are in the same pane, and when all servos are in mid positions, the mixing arms are 90 degrees to the frames. If not, adjust the pushrods to make them so. Both elevator arms,$and aileron triangle should be 90 degrees, and the swashplate should be level when the mixing arms are 90 degrees, and the servos are in mid positions. Eventhough you've followed the manual to set up all pushrods, you might not achieve this, some adjustments had to be made. Also, don't use differential ATVs on one channel to set up ANY controls, except for the gyro in some case. (Differential ATV means use one figure for one side of control and different figure for another side. e.g. 80%ATV for left aileron, 85%ATV for right aileron is differential ATV) Differential ATV means your helicopter is not set up right, and if you use differential ATVs in throttle and pitch channels, your curve settings WILL BE DISTORTED. Use different lengths of servo horns to achieve the desired travel, and don't use the software on the radio to compensate wrong pushrod setups.
While mounting the tail boom to the tail boom holder, use some tapes to wrap the end of the tail boom before sitting it into the holder. Without the tape, the tail boom will slip into the holder and the belt tension will lost after about one or two flights. If the belt tension is loosen, then the belt might come loose while flying, then you'll end up with no tail rotor power! If you use the plastic tail boom holder, try drill two 3mm holes on each side of the holder, and use 3mm setscrews to secure the tail boom in place.
When you are assembling the tail pushrod, don't overtighten the pushrod clamps, cause you might damage the screw hole and it might come loose during flight. Also, after setting up the tail pushrod, make sure it is smooth enough, if not, move or turn the pushrod clamps to achieve this. You can try using your hand to push/pull the rod to feel the smoothness of it.
If your Ergo is not a Type II, you might want a bigger fuel tank. If you do, you need to get the Type II fuel tank (JR#60333) and K&S large fuel tank holder (K&S#561). You have to cut out some materials from the lower main frame bracket for the fuel tank, stick in the large fuel tank, and secure it with the K&S part. By doing this, it gives you about 2 more minutes of flight time.
After doing the above, your Ergo should be smooth. I tried to keep my upgrade recommendation less, cause I am a bad example of an upgrade freak! ( I had two Ergos totally built up with upgrade parts). If you have more questions, feel free to e-mail me.