E7SE and Low Head Speed

[johncclayton]

Hi

I have previously owned a Gaui X7, Gaui X5 and a Goblin 570.  I am slowly changing my style to prefer low head speed setups.

As I recently completely destroyed the X7 (only the servos, rotor head, main gear and screws/bolts survived) I’m considering getting an E7 and I’d like to know if its well suited to RPM’s within a range of 1100 - 1500.  For example, is there a need to speed up the tail or use larger blades than those in the delivered kit?  Is a 4.9:1 tail ratio good enough for say 1300 when using 106mm tail blades?

If anyone has concrete setup recommendations or could share their own stories about flying low head speed setups that'd be greatly appreciated.

Thanks
--
John Clayton
Switzerland

[Chris Sexton]

Hello!

Welcome to the synergy forums!

The E7se is a great low head speed machine. The tail ratio of 4.9:1 is one of the faster on the market in a stock kit and it performs well with low head speed!

Like all things when you turn the head that slow it is easier to blow out the tail but it's a very capable setup.

Here is a video of Matt flying the original E7 at 1100 rpm. This model was using the older 4.5:1 tail and it still performed very well!

http://youtu.be/9lISQu3LSdk

Keep your setup light, 4000-4400mah packs and run 116 tails, you will love the E7se at 1100-1300rpm.


Sent from my iPhone using Tapatalk

[johncclayton]

Thanks Chris, I appreciate it.

I presume that's a 6S setup in the video?

So if I understand right, a lower head speed setup should be something like:
- 12s == 2x 4000 mAh packs
- 11t main pinion
- 4.9:1 tail ratio paired with 116 tail blades

Can I run 716's as well as 116 tails?

Thanks

[Chris Sexton]

Thanks Chris, I appreciate it.

I presume that's a 6S setup in the video?

So if I understand right, a lower head speed setup should be something like:
- 12s == 2x 4000 mAh packs
- 11t main pinion
- 4.9:1 tail ratio paired with 116 tail blades

Can I run 716's as well as 116 tails?

Thanks

The E7se head is lower than the standard E7 head, so if you want to run 716 mains with 116 tails you will need to pull the tail box back about 5mm.  Not a problem, the boom goes into the tail box over an inch and the whole tail box is a clamp. Just Pin the boom for extra security.

12s 4000mAh is a good place to start! I do believe you are right, and that video of Matt's is on 6s with a jumper to complete the series plug.

[okanor]

Hello John! I have been flying low head speed for about 3 years now and have a dedicated bird for it. I have ran an E7 before with 716 mains and 116 tails (4.5:1 tail ratio), it works very well. I currently have a Synergy E5 stretched to run 696 main blades with 106 tails (4.9:1 tail ratio). My setup is a bit different from your average setup, since it was purpose built for LHS. I have tried quite a range of motors for LHS. Like most things there are some good guidelines and some personal preferences. 6s works well and depending on the motor/head speed/gearing you can normally get a solid 9 minutes of flight time out it. I like to keep my motors as light as possible and find that the Scorpion 4035 and 4225 work well in this application for a 700 size bird. I run a 4225 550kv in mine currently and a 14 tooth pinion. I already had this motor from my previous E7 or I would have gone for something slightly higher in KV (650ish). My head speeds are 1200/1350/1500 and I spend a lot of time at 1200 (11+ minute flights). I can do tail slides @ 1200 head speed with this setup and the tail is rock solid, my tail first hurricanes are not all that fast but the tail holds true in these maneuvers as well. I am curious of your flying style and what you would like to get out of your low head speed setup? I am happy to expand more on my setup or expand further on my opinions of LHS setups. Chuck Bole also runs LHS and has played around with 6s-8s setups. I currently run 7s but have played around with 6s-10s setup for LHS. I like the small bump in voltage (allows me to run a smaller pinion) and the additional weight of the 7th cell. This allows my run my pack further in the chassis. 

[johncclayton]

Hi Okanor,

Thank you for the information - it is much appreciated.

I’m new to low head speed - having discovered it about 4 months ago on my Gaui X7.  This last week I spent time in Croatia at a heli holiday with Hugo Markes and Tobias Wilhelm (both great pilots), mixing heli lessons with  flying/practising on my own and with others as much as I could.  I’m presently quite comfortable flying in all orientations, my funnels and hurricanes need more work, my piro flips in both directions are coming along but I still feel they take up too much space.  I am starting to be able to fly fluid transitions between rolls, funnels, loops and piro flips - a huge improvement on my previous style which included lots of "reset to tail in before thinking about the  next move" events.

I am going LHS because to fly in this style is quite relaxing and calm.  Low head speed flight is more like a slow dance than a mad race to the finish.  I have found that I prefer to perfect each move, to feel it as I control the model.  The conscious effort to flying each arc and transition with intent is more pleasing than flying hard - perhaps because I don’t yet have the required skill to elegantly control harder 3D flight.

I’ve not tried 6S yet, nor any head speed on the 700 heli’s lower than about 1500 - but I would very much like to.  The purchase of the E7 is one of need, as I drove the X7 in so hard last week that the only pieces left fit in the left hand compartment of my toolchest - that’s a shame, but at the same time I look forward to trying something new.

I would really welcome as much input as possible about different setup choices and their pro’s / contras. My current plan is to go with an E7 that it’s using larger blades (I also wish to practise autos), both head and tails - so 715 and 116’s along with a 4.9:1 ratio and on my Heli Jive a throttle curve of 50%.  I have *assumed* that a 11T pinion will be suitable in the sense that it allows a lower head speed with more efficiency at the motor, but I’ll also pair that with an ESC capable of active freewheeling.   

The 550kv motor with a 14T pinion on E7, that sounds like a 6 or 7S setup, correct?  Wasn’t sure.

One question immediately; you mentioned that you like the extra weight of 7S.  I’m curious, what does “too light” feel like then?  The Gaui X7 wasn’t light, and I’m hoping to have an E7SE that runs quite light in order to create more lift on autos and extend battery time. 

Thanks
--
John Clayton
Switzerland

[johncclayton]

Hi Okanor,

I presume you run the 4225 & 14t pinion on 6S - what's the throttle level you run and the AMP draw you are seeing in this configuration?

Cheers

[okanor]

Hi Okanor,

I presume you run the 4225 & 14t pinion on 6S - what's the throttle level you run and the AMP draw you are seeing in this configuration?

Cheers

Scorpion 4225 w/a 14 tooth pinion on 7s 5000mah 45c. I run the ikon gov so I don't run % to achieve head speed.I run 30%/70%/100%, but there is still head room. When I was running a castle on it I was averging 18-22 amps average and could spike @ 90 amps if really tried but that was extremely brief.

I prefer the 7s for weight so I can run the pack further in the chassis and so I can run a smaller pinion to achieve my desired head speed. I moved to the 14 tooth when I bumped up 100 rpm on the head to 1200-1500.

[johncclayton]

Thanks for sharing the info - I appreciate it.  You mentioned that you had tried a few motors - can you expand a bit on that and provide you personal pro/cons?  I'm assuming there were two motivations: weight and power consumption?

Thanks again,
--
John Clayton
Switzerland

[okanor]

I find that smaller motors do just fine on the lower head speed setups and tend to be lighter. I run a Scorpion 4225 550kv but I have tried a Scorpion 4526 and a 4530 but I did not see any improved power from them in low head speed setups.

[johncclayton]

Makes sense. Was there an rpm range at which you felt it did make a difference having a larger
Motor? I guess north of 1900 but keen on knowing if you noticed anything when testing.