E640 Helical Gearing

[phoenixheli]

Has anyone flown an e640 with a helical gear set? If so, was it worth the reduction in gear noise or not?

My objective is to reduce gear whine and hear more of the rotors as possible. I've only been able to find a helical gear set for the main and pinion but nothing for the tail drive gears.

[codfish124]

I don't think they make it for the tail and i never flew mine with the stock gear so I don't know about a change in noise the helical gears are for higher power systems is what I was told.. if you look up my videos you might beable to make a noise compareison

[Dennis P]

I have only flown mine with the stock straight cut gears and the gear noise is not bad at all.No problem hearing the rotor blades at all.I am going to be doing a motor swap in the near future and will be changing out the gears . I may be able to tell you the difference then ?

[phoenixheli]

Thanks for the input. I've been on a mission the past few months to find power train components and combinations that will keep unwanted noise down in an e640 without heavy modifications.

The best setup I have seen in any heli uses a belt drive between the motor and main gear combined with a directly driven belt to the tail. There's no gear to gear contact of any kind and all you hear is the motor and lots or rotor slapping the wind. However, it wasn't in an e640. I guess the helical main gear and pinion is a start along with a quiet motor.

I was able to find a video comparing the sound of straight cut vs helical in a t600. Seems to make some difference.

YouTube

YouTube

The straight gear flights almost remind me of the sound of my ol swift 16.

[Furious Predator]

Century makes Helical metal tail gears for the Raven/Hawk/NX50 and the Predator. One of those sets might be able to retrofit to the 640's....or they may come out with some soon. I hope so, they are great gears!

[codfish124]

They are working on metal gears for the tail on the E640 its not for noise and will probably make more noise

[Furious Predator]

From my experience with the metal helical tail gears on the 50 and 90, the tail is pretty quiet. You hear the main&crown gears.

This of course assumes the tail gears are meshed just right. They are much more picky when compared to spur or beveled gears. The metal tail gear upgrade for the 50 comes with very thin washers to dial in the mesh.

If they do come out with an upgrade for the 640's, I would also like to see a closed tail box. I like keeping the metal gears well greased.

[codfish124]

If u want to try the helical stuff for cheap I have a set for 20 I could sell you

[phoenixheli]

Thanks for the offer, but I don't plan on spending any more money for a while yet. lol. My focus is on getting an xera 4030 3y, then I'll start on helical gearing. I just like to get a good idea on something well in advance.