Check your Tail Drive Shaft

[James Kovach]

I was getting some odd noise from the tail drive of my Frenzy. I was thinking maybe the bearings were getting notchy. So I removed the tail drive setup to find what you see pictured below.

The top bearing was wearing a groove into the tail drive shaft. This is not the first time I have seen this. Century Hawk/Ravens have the same issue with their counter gear shafts. The problem is that the shaft is just a little too small for the inner race so the shaft spins inside the race rather then the shaft and race spinning together. So make sure you keep an eye on this. If left unattended too, it is quite possible for that to wear away enough that it will snap off.

The solution with the Hawk/Ravens was to red lock-tite the inner bearing race to the shaft. I would suggest you do this. Just make sure you have it installed before the red lock-tite sets up. Also, be very careful to NOT get ANY of the red lock-tite in the bearing. You wont have a bearing that spins anymore .

[tessex]

James, Good to know! Thanks!! -- Tom

[grnmac1]

I could be wrong, but it looks to me that you may have had the belt to tight?

[James Kovach]

Belt was not tight.

Head the warning or not. Doesn't take long to check it.

[James Kovach]

I just got done talking with Dan at Amain Hobbies. They pulled two helis that they have been flying to inspect the tail drive shaft and found that the shafts were wearing in the same manner. One was flown by Ben for around 15 flights. The other I do not recall how many flights. But they both had their tail drive shafts wearing.

Dan said they forwarded the info off to JS Models. So I am sure they will come up with a solution. Hopefully just a harder shaft will fix the problem.

So I would pull your tail drives and take a look at that shaft. Last thing you want is that shaft snapping while in flight. If it is worn, you can use the shaft off the orginal assembly if you still have it. Just make sure you lock-tite the bearing inner races to the shaft. This should take care of the problem.

[James Kovach]

Got an email from Dan today. JS is going to start putting harder shafts in the tail drive systems. I would highly suggest you lock-tite your bearings if you haven't yet.