RJX FBL Head not centered lots of vibrations

[heliaddx]

I've converted my Trex 600ESP FB to the RJX FBL head.

Even without the blades on when you spool up the center hub (stopper) seems to wonk side to side as it spins to speed - it's quite visbly unaligned.

Is this normal?

If not how do I fix this?

I've refitted the head onto the main shaft to make sure it fit's snugly and flushed to the tip of the main shaft before tightening everything up.

Helis runs smoother with the stock FB head.

Hovering with the RJX head makes the whole heli vibrate which is quite visible on the skids of the heli.

Any advise would be great.

[davor6696]

I saw two versions of 50 FBL head, one nickel plated aluminium, and other is anodised.
Nickel plated has larger bore (+0.15 mm) so it has play on main shaft, anodised is better fitted.
Anodised can be found on e-bay, nickel plated is from HK.
Anodised may be "real" RJX and nickel plated may be copy.
Which one is your's?

[heraldo]

Contact the seller. I had play in the grips and had a new one sent to me without question.


Sent from my iPhone using Tapatalk

[superjon78]

I saw the same issue on a friends 600 as well. His head was genuine RJX and was chrome. We measured the sizes of everything and found that the bore way up inside the head was too big compared to the main shaft. Sure, the bottom clamped tight and centered itself when mounted. However, once the machine comes up to speed, the mass at the top would always cause the head to "shift" to one side or the other...ultimately putting everything out of balance.
In my opinion, I think the head should be replaced. However, he simply shimmed the tip of the main shaft until it was a snug fit. I don't like rigged fixes, but it seems to be working so far. He just had to make sure his shim was the same thickness all the way around the shaft to ensure the head was centered.

Good luck with yours.