one way bearing

[t-driver]

my one way bearing feels a bit stiff if i turn the head with my fingers.
if i turn on the flybar fast,(without the blades) and let go,
the head spins for another 3 turns than stops. sometimes it doesn't even disengage the main gear.

i tried all kind of things to fix that,but ones i secure the upper grub screw from the mast collar it gets stiff again. :confused: (without it it is perfectly free)
the heli hasn't crashed yet,so everything is still ok and nothing is bend.
it also hasn't been flown much.

any suggestions?

[crabfu]

I have 2 gaui200's and one of them did this, the other one did not. The stiff one flew as well as the loose one, I could not tell the difference since I only auto inches from the ground :) I changed out so many things to try to fix this problem, but could not... upper and lower collars, main shaft, main gear, shaft support with bearings, shaft support holder.... took the whole frame apart in the process.... like you've said, loosen the collar and it's free, secure the collar and it's tight and won't turn much at all, was driving me nuts even though it was flying just fine.

So I did finally fix it... but by accident. One day I had a bit of vibration, trying to track down the issue, and since I had put in a new straight shaft, I decided to see if my head is bent or something. I was trying to do this by marking the center of the top of the head, sort of like a center punch, and spin the rotor to see if the center is a dot for is going around in a circle. So I put a screw driver and pushed down a bit on the top of the head to make the mark on the soft aluminum. When I spun it to check, it all of a sudden spun smooth and free, I did not loosen the collar or done anything else. My guess is by pressing down on the head, that it pushed the bearing below the gear down a bit to have better tolerance or something... I dunno. And since I am not sure, I wouldn't recommend you or anything do this, because it may cause other issues and not fix the problem. But thought I'd share what ended up fixing it for me :)

-Crabfu

[t-driver]

i know it won't effect flying,
but i also like to try some autorotation,this way it's almost impossible.

i may try out your "trick"

[mjr_larkin]

i know it won't effect flying,
but i also like to try some autorotation,this way it's almost impossible.

i may try out your "trick"
check the orientation of the mast collar above the main gear. Those mast collars are different stock than spare. You want it flipped so that the raised end is on the gear side. this lifts that grub screw above the gear so it doesn't grind on the plastic. Might want to check that out.

[crabfu]

check the orientation of the mast collar above the main gear. Those mast collars are different stock than spare. You want it flipped so that the raised end is on the gear side. this lifts that grub screw above the gear so it doesn't grind on the plastic. Might want to check that out.

in my case, I've tried flipping the collars.... MANY times, and tried a couple of sets, didn't make a difference, it's always tight. But they are the spares collars, not stock. My last push accident that made it work, has the raised end on top, not towards the gears, and it just all of the sudden rotated smoothly.

-Crabfu

[t-driver]

check the orientation of the mast collar above the main gear. Those mast collars are different stock than spare. You want it flipped so that the raised end is on the gear side. this lifts that grub screw above the gear so it doesn't grind on the plastic. Might want to check that out.

i checked,everything is fine.

in my case, I've tried flipping the collars.... MANY times, and tried a couple of sets, didn't make a difference, it's always tight. But they are the spares collars, not stock. My last push accident that made it work, has the raised end on top, not towards the gears, and it just all of the sudden rotated smoothly.

-Crabfu

i'm thinking maybe the upper collar is pushing too hard on the bearing.
i may try some things this weekend.

[t-driver]

well, after crabfu's instruction i did a mix of it, and something different.

i unscrewed the upper collars grub screw,and by pushing and holding the shaft softly down,i screwed the grub screw back in.
the rotor was only a tiny bit easier to spin at that time,but after 10 minutes of flying it spins perfectly free !! :thumbup:

[crabfu]

Sweeeeeeeeeeet :) Glad that you got it fixed.... time to auto :)

-Crabfu