Raptor e700 tail ratio

[CromedCm]

Hi everyone,

I was looking through some videos of Nick Maxwell flying the e700 and noticed in the description his tail ratio was 4.71. I am not sure what this means, but have an idea. So i am not sure if my e700s are running this ratio, but i can imagine its an upgrade to the tail performance. Could someone explain to me what this is, how it will affect what blades you can run and the performance?

Thanks in advance

[George J]

They bought out an upgrade tail gear set which gave a faster gear ratio and this allows the use of 105mm tail blades instead of 115/120mm blades and better performing tail in general. You change the front tail gearbox gear and the autorotation gear, it's worthwhile doing as I've stripped gears in flight on the old ratio but had no issues since.

[bigpops]

They bought out an upgrade tail gear set which gave a faster gear ratio and this allows the use of 105mm tail blades instead of 115/120mm blades and better performing tail in general. You change the front tail gearbox gears and the autorotation gear, it's worthwhile doing as I've stripped gears in flight on the old ratio but had no issues since.

Are you sure they weren't the old V1 tail drive gears? One of the changes on the V2 was the new ribbed autorotation gear and a new tail box gear to match it. I know I bought the new version as the old ones were known to strip in flight.

Obviously the 4.7:1 gears are all the new type.

[r4nd0m]

Both Nick and Simone have highlighted that 106s are the longest tail blades you should run with the new tail ratio everything else could completely destroy the tail under certain conditions - when running more than 2050rpm and sometimes even lower.

with the older ratio you could also longer ones ...

I run 696 rail mains and 106 rail tail blades and apart from "killing" the tail gears last weekend I never had an issue - I received the upgraded parts as part of a V1 upgraded box - you would have found a new drive pulley PV1657 in a separate bag in the box and the upgraded front tail gearbox gears supplied as usual along with the V1 canopy

if I remember correctly the kit came with 106s or 105s so you didnt had the required authority unless you switched them to 115/120s

[bigpops]

Yeah it did. I've never used the supplied 105s.

They are ridiculously light though. Over a gram lighter, each, than the Rail 105s I bought for my Trex.

I've had KBDD 112mm on there since I built it, but running the V2 gears on the old 4.2:1 ratio. Never had any tail problems.

[CromedCm]

Both Nick and Simone have highlighted that 106s are the longest tail blades you should run with the new tail ratio everything else could completely destroy the tail under certain conditions - when running more than 2050rpm and sometimes even lower.

with the older ratio you could also longer ones ...

I run 696 rail mains and 106 rail tail blades and apart from "killing" the tail gears last weekend I never had an issue - I received the upgraded parts as part of a V1 upgraded box - you would have found a new drive pulley PV1657 in a separate bag in the box and the upgraded front tail gearbox gears supplied as usual along with the V1 canopy

if I remember correctly the kit came with 106s or 105s so you didnt had the required authority unless you switched them to 115/120s

I guess then the e700 i have flying atm is on the older gear ratio as i am running edge 115mm and have not had any issues.

I also have another e700 which is not fully ready, but it come with 105mm blades which i found strange at the time as i thought you could only run 115mm. I guess its on the new ratio.

[waveydavey]

It is on the original ratio

[bigpops]

Yes, even new V2 E700s have the old ratio. The 4.7:1 is an upgrade option, not a necessity.

[CromedCm]

Ok so i have counted both of the helis tail drive gears and am getting 26 for both. So its the new 111t drive pulley that is changing the ratio?

I am Hoping to get both of these helis flying the same, so i am going to have them both on the new ratio 4.71 with 105 tail blades

[bigpops]

The new ratio comes as a pair of gears. Both need to be changed.

[George J]

Are you sure they weren't the old V1 tail drive gears?

Thats what I said surely!!

[r4nd0m]

The new ratio comes as a pair of gears. Both need to be changed.

seems to be correct, just checked my upgraded V1 came with PV1651 Tail Drive Gear Set (which includes the PV1653 Tail Drive Gear 26T) but with the upgradedP V1657 111T Drive Pulley V2

so that wasnt the PV6140 Tail Drive Gear 4.71 upgrade

[CromedCm]

Just went to buy the PV6140 upgrade from fastlad but someone else just did :/ now its out of stock

[bigpops]

Thats what I said surely!!

You said you stripped the old ratio. You can get the new strengthened gears with the old ratio (as ship with the V2s), so it could have been either type of gear.

[r4nd0m]

Just went to buy the PV6140 upgrade from fastlad but someone else just did :/ now its out of stock

Thunder Tiger PV6140 - Thunder Tiger E700 V2 4:71 Tail Drive Gear