i bought a used nexus..also i am new to helis...sometimes when i run up the engine i have no tail rotor control...tail rotor spins but no control..heli just spins around..pulled engine..clutch and shoes looks fine..gears look to be in aligment..i can lower the throttle and rerun up the throttle..everything works fine...this doesn't happen everytime.....ok what do i try next???

I would first recomend that you verify that the servos actually move before each flight. Do this with the engine off and on. BEFORE EVERY flight no matter what. Try not to find out about the problems once you are airborne. It could be anything from the RX to the Gyro to the servo. The choice is yours. Try to get it to fail on the ground and then start checking the wires and the gyro. You can verify the RX by plugging the servo directly into the RX, DO NOT fly it this way, but just check iton the ground, in fact I would recomend that you nt run up the engine, and if you do do not try to pull it into a hover.

i have run 5 tanks of fuel..can only achieve a 1 foot hover... the rudder servo is workin fine and the tail blades are rotating..just not holding the tail still.....yes i always range check..have 10+ r/c in planes..oh the gryo is workin too ..............thanks!!

How much sensitivity is set on the gain of the gyro?
Is the gyro set to compensate in the right direction?
Is the tail rotor servo set to right direction, right rudder = nose right, left rudder= nose left

Are the tail blades facing the right direction and not on the heli backwards?

These are just a few things that could be your problem.

David

Check the set screw where the tail drive gear connects to the main gear... is it missing? If it is, the tail may spin sometimes but won't fully grab onto the drive wire.

when the rotor is workin right the helis flys well....except for my lack of control..after work i'll check set screw for tightness.......thanks for all the help!!!!!!!!!!!

I have a nexus also and have had the same problem with no tail rotor control. I found the tail rotor pitch change arm loose on the left hand thread brass bushing this causes a lot of slop and when the gyro tries to work it just keeps going around and when you try to work the rudder controls it will become really erratic. If you find this I suggest drilling a small hole in the brass bushing in the center area where the control arm runs also a small hole in the top of the control arm hookup bushing almost directly across from the pin. This will let you oil all bushing or bearings and the tail rotor shaft under the pitch control arm. This is only my opinion.

thanks blackrockminer...i'll try that!!

I had the same problem with my Nexus, the tail pitch plate threads stripped on the pitch slider... the replacement pitch slider comes with a lock ring to keep the pitch plate from coming loose ( No. H3045 ).

Fortunately I had just got proficient at fwd. flt. and a good breeze was blowing when I had an uncommanded piroette on takeoff. ie: weathervaning is a good thing. I found this site after I had problems, so we're not the first people this has happened to!!

http://www.heliguy.com/nexus/nexustips.html

Good Luck, Dale

Hi guy,
Been flying a Nexus 30 for 5 months now. Many moons ago, I removed the brass/bronze bushings in the tail pitch slider, and replaced them with ball bearings my LHS had in stock. Solved tons of problems with that problem. The LHS charged me $10.00 for the set. Kyosho has them as an upgrade, but they wanted $14.00 for the same thing. Oil them with real light weight oil, like turbine oil, and keek oiling them on a regular basis.
Only upgrade on this bird except Century blades (wood), and this thing flys great. Lots of luck..... Jack Hall

what is the size of the bearing to replace the tail pitch slider bushing?

The're 6X10 mm . You'll need 2. My LHS had them both in flanged (big on one side), and unflanged. You need the unflanged style. (Normal looking bearing). You should oil them when installing them and on a regular basis after that. In fact, On mine, if it moves, I oil it. I got into a practice after a flying session to clean the whole machine, and doing the oiling then. As well, after every 5th or 6th session, I remove the tail assembly and grease the wire drive, as well as the tail gearcase.
Heli's are a lot more high maintanance item than a plane. Do it regularly, and you'll get good service out of it.

alright thanks i'll go ahead and buy those 6x10mm bearings

One more thing. This is crazy, but it happened to me. I assembled the kit myself, and everything seemed fine. Took it to the field to have a seasoned club member set it up, and do the first flight for me.
Well, he set it up, then took it to the line, spooled it up, and just at lift off it was loosing tail control. Now this is a brand new everything. He's one great heli pilot. He took it back to the truck, and ripped the tail assembly apart. Turned out that Kyosho had supplied the wrong wire drive, and it was just short enough that it would engage the the takeoff spline and then release and then catch again. Kyosho makes 3 different wire drives of different lengths. Mine was about 3/4 inch shorter than the one it called for. New wire drive solved the problem. Maybe..................
Jack Hall