HELP My front gear keeps stripping

[herman munster]

I posted this problem a few days ago and today I got my replacement gears from Ready Heli so I installed the gear, reset the backlash on the pinion and front gear,this time setting it a little tighter, double checked the tailbelt to make sure it wasn't twisted and took heli outside to check it out. It spools up fine and then I increase throttle, get it light on the skids then shut it down and the front gear is stripped again!!!! So I get the other front gear (ordered 2) install it reset the backlash just a tad less tight take it out side again and spool it up to about 1/2 throttle and then shut it down and check the gear, everything looks OK, so I spool it up to 1/2 throttle and back down again 3 more times checking the gear each time and it's doing fine, so I go ahead and spool up get it light on the skids a little more throttle get it to hover about 4 inches off the ground and then set it down and #*!@#$ If the front gear isn't stripped again. I am totally frustrated and can't figure out why this is happening. Does anyone have any ideas? I am running a Z20-980KV motor with Revco 19T pinion and Revco 68T front gear and Revco 61T rear.

[worldofmaya]

Did you have the same problem with Gaui pinions & gears?
-klaus

[herman munster]

Did you have the same problem with Gaui pinions & gears?
-klaus

Yea the first time it was Gaui OK gears and pinion, I changed to the Revco gears to get the head speed a bit lower

[mjdee14]

something is definately not right here....if your using all compatible gears...you say they are all revco....and yor sure....because if your not....the gear mesh is not the same...

Then have you checked and have no excessive binding?

whne you firstput is together..and set the mesh....does it look like the gears mesh correctly all the way around?


The Z20 is not that much of a powerhouse to strip gears that are of the correct type.

You are overlooking something basic.....why not try the gaui...we all know that works...and gears are cheap. with the 50t front you have many more gear ratios...

I run the 14t pinion, 42t 1st, 20t OWB and 61t main with my z20 and love it.

[skigolfmike]

OWB shaft bearings are probably shot. Or, the RevCo gears are too soft. I melted one in one flight on mine. Went back to Hurri 550 gears. If you get the 42, 50 60 & 61 Mains with the 13-16 pinions you can get just about any gearing you want.

[herman munster]

something is definately not right here....if your using all compatible gears...you say they are all revco....and yor sure....because if your not....the gear mesh is not the same...

Then have you checked and have no excessive binding?

whne you firstput is together..and set the mesh....does it look like the gears mesh correctly all the way around?


The Z20 is not that much of a powerhouse to strip gears that are of the correct type.

You are overlooking something basic.....why not try the gaui...we all know that works...and gears are cheap. with the 50t front you have many more gear ratios...

I run the 14t pinion, 42t 1st, 20t OWB and 61t main with my z20 and love it.

The very first time I spooled it up it stripped the front gear and that was with the Gaui OK gears, I'll check the one way bearing,, like Mike suggested, my kit came with the 19T but I put a 20T in it because of all the reports of the 19T failing.

[Mikej]

If you do go back to the Gaui gears then it is probably worth going with a 50T primary - it gives more options on gearing and also pushes the Z20A a bit further away which it needs - other wise it can bind on the pitch and elevator lever screws

[herman munster]

Well, checked the OWB and there's nothing wrong with it , it is nice and smooth

[skigolfmike]

I was talking about the bearings the shaft runs in, i.e. in the frame bearing blocks. Take off the motor mount and see if there is any play in the top of the shaft.

[mjdee14]

Is something that has happened since you first got the heli.....? or has this happened after a while of owning it...like it flew normal for a certain period then started striping gears..?

maybe post some closeups of the geartrain....and something might pop out at us...

[herman munster]

Is something that has happened since you first got the heli.....? or has this happened after a while of owning it...like it flew normal for a certain period then started striping gears..?

maybe post some closeups of the geartrain....and something might pop out at us...

This happenned on my first spool up, I haven't even gotten a chance to fly it yet except for my 15 second hover today.

[herman munster]

I was talking about the bearings the shaft runs in, i.e. in the frame bearing blocks. Take off the motor mount and see if there is any play in the top of the shaft.

Checked those bearings and they are fine.

[skigolfmike]

14/50 with the stock gears will give you the same ratio. They are .8mod so setting the mesh is a little less critical.

[Sircrashalott]

Herman......did you find the problem....?

if so please share......I am in the same boat......:YeaBaby:

Do you have the plastic frames also..........?

[herman munster]

I ended up replacing the OWB Shaft and haven't had a stripped gear since and I do have the plastic frames

[jujiro]

ahh was going to say check that. Think that might have been why my hurry has been stripping gears. Odd to as the gear would melt after 50 seconds of just hovering did that twice before I thought to check the OWB and when I did I found that it was missing some pins. Can't believe that OWB went bad so fast as I just recently put it in there and I hardly fly it since it's been giving me problems :mad:. Glad to hear that you got your problem sorted ^^;

[vicrc]

I guess I been lucky with my OWB, 300+ flights. I wonder if there is too much play between the bearing casing and the plastic block it sits in. If the bearing is loose it might cause for some problems. Are you guys putting shoe goo where the bearing goes to prevent the bearings from turning on its outside casing and eating up the plastic housing? Just a thought.

Does it seem like it tends to happen more with the number of flights your putting in the heli?