This machine was purchased from Cyberheli.

All the goodies about to be unpacked.

All the bits, note the showcase box to the left.

The helical cut main gear with the auto hub installed.

The power module.

Power module with main gear and pinion.

The main shaft with the collar installed.

Assembled power module.

The Sylphide 90 is JR Heli Divisions top shelf FAI machine. It's loaded with all the nice flash, 'lick your lips' bits that you expect in a top of the line machine. The Sylphide's competitors include machines such as the Kyosho Caliber 90, Hirobo Eagle, and Xcell Tempest FAI to name a few.

I purchased my Sylphide a month or two ago already built up. I had done the setup flights, and infact, most of the flying this machine before I bought it, but I had not built it. I was, and still am, very happy with the Sylphide.

However, the opportunity presented itself for me to build a brand new one for a mate of mine which would allow me to see what the machine is like to build, so I jumped at the chance.

This machine was going to be the same as mine, full of Futaba 9252 digital servos, Futaba GY601 gyro, Futaba GV-1 governor and a Funtech muffler. The only point of difference on this machine was that it was going to be powered by a YS 91 instead of the OS 91 PS I have in my machine. Having had no practical experience with a YS engine, I was keen to see how this would go, especially after seeing Kazuyuki Sensui's YS 91 powered machine go in Bali.

PRESENTATION:
The Sylphide arrives in the box packed like most other JR helis however all the nice 'blingy' bits are nicely showcased in a cardboard box with a see through cover!

Included in this 'showcase' box is the large billet aluminium transmission case unique to the Sylphide. As we've come to expect from JR, all the parts are beautifully machined.

As always, the parts are broken down into bags which you assemble the contents and which relate to a specific section in the instruction manual.

The instruction manual that came with this machine was actually printed in English whereas the one that came with mine was all Japanese.

The fully assembled head comes in it's own box.

ASSEMBLY:
Transmission:
As with all JR machines, assembly is very straight forward and clear. You begin by assembling the CCPM levers and the clutch mechanism.

The Sylphide has a stacked frame design built around two large aluminium blocks called the 'Power Module'.

The transmission is helical cut (as opposed to straight cut gears which most helicopters have), this is to cut down on transmission noise which I can personally attest to. The pinion is threaded into the clutch bell which is then loctited into a bearing block which bolts onto the power module. It's here where I find the only slight disappointment I had with the whole machine. This is that the bottom of the clutch bell itself is not supported by anything apart from the start shaft which goes through it to the clutch. This is fairly common, however on the Vigors, the clutch bell is held in place top and bottom by ball bearings so the bell cannot move at all. This prevents 'fretting' of the pinion in the bearing if the loctite happens to let go. Eventually this will get worse and the pinion will have to be replaced. I had this happen a couple of times on my old Ergo Z230 gasser and the little Ergos. It's never happened on the Vigors.
It would have been nice to have the clutch bell supported top and bottom on the Sylphide as already on my one which has probably done about 60 flights, has had to be re-loctited into the top bearing. It's something I will keep an eye on in future.

Early Sylphides seemed to have a problem with autorotation bearings letting go or locking up. Apparently JR changed the hub and now subsequent machines have been fine. Certainly my machine has never had a problem. I was certainly impressed with the whole auto hub assembly on this machine. It looks very industrial when compared to the Vigor and is certainly up there on par with the Tempest which had a very serious one way bearing in my opinion.

As you'd expect, it's a split gear drive system. The belt driven tail is driven from a gear bolted to the mainshaft and the maingear/auto hub assembly sits below that.

The main shaft has a thrust bearing at the bottom of it just above the Jesus bolt. The auto hub assembly is secured to a separate autorotation shaft which is bolted and set screwed to the mainshaft.

With the hub assemblies and mainshaft in place in the transmission module (the large aluminum block), the drive pinion/clutch bell assembly is then bolted to the front.

Frame Assembly/Engine Mount:
With the drive train now assembled, the second large aluminium section is now temporarily bolted on. This forms the engine mount and also the basis for the frame sections to attach to.

Skid rails are attached to the bottom of the frames and the elevator 'A' assembly is installed into the frames just prior to the power module being squeezed in between the frames. The instruction manual reckoned it would just slide on in, but I found I had to loosen off the frame cross member bolts in order to spread the frames so the main gear could be positioned. Not a big deal.

The servo frame assembly is the next item to assemble and install and it's here where I was caught out. I should have twigged, but it was late and I had the flu (enough of a disclaimer?), but the servo frame assembly has a definite left and right frame. I hadn't picked up on this until I went to install the servos and found that nothing was going to go in right. This meant trying to get the servo frame assembly out of the main frames to swap the frames around and reinstall. This wouldn't normally be the pain in the ass I'm making it out to be except for the way in which JR have decided to attach the servo frames to the main frames. They've decided that instead of using frame standoffs and long bolts that go from the main frames, through the standoffs to the servo frames, they would use standoffs with threads that you wind in, then in turn, wind into the servo frames. This means you only use a little bolt to secure the main frames to the standoff which isn't a problem, except when you have to try and get one of those standoffs out (so you can get the servo frames out) and you've perhaps used more loctite than you should have!

JR have also seen fit to use the threaded standoff method to secure the back of the radio tray to the mainframes as well.

The rear mounted fuel tank is a long narrow affair and in the past I've had issues where the clunk has not been able to scavenge enough when the fuel level gets lower.
The tank is supported in rubber mounts between the frames.

The landing gear is made up of Voyager cross members with long skids. I think the theory here being to ensure light weight. The landing gear is attached to the skid rails on the bottom of the frames by rubber shock absorbers.

Page Two