okay, my two SRX 200 triblades.

bird one Rakon head, with EH200 4100 kv motor, 13t opps 14T ! pinion, rocket ship to fly

Maximum head speed, a stonking 4256 RPM !!! static thrust test 700 grams, flying weight 290 grams, thats decent thrust to weight = 2.14 times ! 150mm blades.

bird two. Microheli head with modified stock 6 degree main blades and repitched 175mm blades. stock motor stock 11t pinion (tried a 13t but the rotor is just to loaded with the 3 blades) feels smooth and fast.

Maximum head speed 3074 rpm. static thrust, hit 900 grams then pulled back to 800 grams constant !!!~ 2.71 thrust to weight !!!

currently the pitch is still a bit steep and more adjustments needed should see the rpm go up. The stock motor has good torque and thrives in the higher loads, where as the EH200 is a revver and loves the shorter blades on the stock rakon setup.......

both fly superb, not going back to a stocker now.........


with the stock drive line and 8 degree xtreme blades we saw around 3600 rpm, jumping to a 13T we saw 3800 rpm and a big improvement in how it flew. 14 T was better but the rpm gain tampered off, maybe 3875. For fp birds they seem best in the 70 to 80 efficency range, above 80 means your under geared and below 70 your over geared. no thrust test though.

See spreadsheet data below. efficiency = max thrusted loaded rpm / unload rpm (based on Kv by volts - found this to be pretty close)

The tri blades stonk! two different builds, two different machines, I like BOTH !

FY 02/03/05 etc fans

New out on aliexpress, full alloy HD differential units, these look superb, ring gear and spider housing is all one piece with bolt on end caps

under hard abuse the plastic diff housing can stretch and the spider gears can slip damaging the teeth

just need banggood to get stock and a sharper pricing and happiness filled!

https://www.aliexpress.com/item/Feiy...9-27c4bee71213

https://www.aliexpress.com/item/Feiy...9-27c4bee71213

https://www.aliexpress.com/item/Feiy...8-f5c7b31d8326

https://www.aliexpress.com/item/Feiy...8-f5c7b31d8326

a decent splined driveshaft, personally don't like the sliding pin drives as they wear like crazy............

https://www.aliexpress.com/item/Feiy...9-27c4bee71213


and new adjustable steering rods, finally !

https://www.aliexpress.com/item/Feiy...7-9a0cd5f82eec

now to get my hands on some !

well after numerous late nights, head scratching and related, I have found a cure.......

the 150mm blades included in these kits are simply to short.................

I altered the pitch setting by sliding the swash locker up the drive shaft, this reduces the pitch, and trimmed the blade roots on the stock 185mm FP blades and fitted these up, and damn it, it flies as docile as.................... no death wobble, zippo, hovers happy as, STUNNED !

The tails working, just humming, with all the extra torque off the head, but no more death wooble...... I can see a longer tail tube to balance the head torque.

So the real problem is the stupidly short bloody blades they fit on these things. !!!!! waste of space.......

There is a still an odd response to the servos due to the fraction off phasing, but at least its well flyable......... I can work with this !!!

Translating this back to the stocker id bet serious $$$ if some one made a set of blades say 10mm longer than the stocker it would make a tremendous difference to the birds stability in stock 2 bladed form.....

Bloody helll..... What a journey this has been..... And i ordered a rakon head yesterday in frustration, arh well. Twin tri blades ....

This is my take on the situation: for the 200 the rx is tuned to suit the response from the stock rotor diameter, at around 400mm, The tri blades, they reduce this to 350mm and put in more pitch...... The rx senses an out of sync aileron roll and puts out...Continue Reading

Lots of choices out there, its really important to get the motor KV / battery / gearing all matched.

there seems to be allot of high Kv "kits" that basically cog like hell and are rubbish to drive,

here is my spreadsheet figuring kv. batteries and gearing compared to the stock setup running a 2S lipo as the base line 100% value.

basically around 30% speed increase is the practical limit - gain

I went to the effort of hunting out the 2845 - 2600kv motor, it works nicely, excellent torque and stellar top end speed on 3S.

2S - the 3100 motor is the pick, 3S the 2600 or 2800 motors are the go.

gears the robinson racing gear sets are the way to go 16t through to 26t works on these setups.

get the bigger 2845 can motors, forget the smaller 2838 motors, gutless in comparison. and anything higher than 3600kv just wont work worth a damn.......

test flights: lots of them, bottom line, flies like crap............

I cant believe how poor this flies. forward flight, okay but vastly different left aileron vs right right, very slow to turn left with allot of lag, right, rolls over nicely and turns 3 times faster,,,,,,,,,,,,. static hover is good and allot of fine tuning on the servo links to get this spot on. very slow on left turn, fast on right aileron.

if I fly in reverse this is where it goes totally pear shaped, heli starts to roll to the right, aileron left to counter response is very poor, wont respond, several near misses. I'm not talking fast flight here just gently bringing it back toward me. stock is fine as doing this. this was a real eye opener, something wierd is going on with the cyclic on the head for sure...........

on spool up and initial hover it can get into a wobble then stablises.

Gains set according to the instructions and fine tuned the tail and filter settings. tails was twitchy at 180 and improved as the gain value was bought back to around 150. definite improvement with tweaking the gains

seems to have allot of pitch, collar is set correctlyin the recess on the driveshaft, moved the collar to the top of the recess notch to takes some pitch off, still seems excessive. might just try locking it higher up.

been right through this several times. Drive shaft bearings and frame are new, servos good, was flying fine in stock form.

observations are - blade grip feathering...Continue Reading

Blade comparision, the microheli blade is a proper symmetrical cp type blade where the stock unit is a typical assymetric profile to generate lift and has the pitch set into the blade root.

The rotor head is a smaller diameter, the blade grips are longer by 10mm versus stock, but the blades are shorter, 150mm vs 185mm stock. Taking into account the difference in blade grip length the rotor dia is 50mm less than stock.

The stock canopy grommets are a right pain in the rear, tend to pull through the canopy and tear with use and fiddly to get on, ive been flying with out the grommets but the canopy vibrates on the mounting pins.....

Microheli grommets have a larger flange and outer diameter to prevent pull through, and the canopy mount pin hole is
larger, rubber is noticably harder. Fit is still tight, and a bit of silicone grease works wonders. 4 in the pack also.

Ready for final install, stunning piece of kit !

Getting it done ! Assembly is pretty straight forward.

Assembly instructions, pretty good

A closer look at the...Continue Reading

Intial un pack and look over of the parts, damn nice i must say !...Continue Reading

attached is my xls spread sheet comparing the stock motor to various aftermarket brushless motors at 2s and 3s and varying pinion sizes. the values are approximate but give good guidance on relative performance vs stock.

This is based on the blue can 2845 motors that are readily available on aliexpress

Currently running the 2845 2600kv on 3s with the 22 pinion, FAST. Yet has good low speed manners and no cogging.

After allot of searching i have found what has turned out to be a perfect upgrade shock. Price is resonable for an all alloy body rebuildable shock.

http://www.banggood.com/REMO-A6955-A...?rmmds=myorder

Excellent build, and prefilled from the factory, so bolt on and go.

A fraction shorter than stock by about 2-3mm, certainly not an issue. Springing and damping seems good , needed a small amout of preload, spot on. Good shock, good price.

Feiyue FY 03 upgrade part 4. Steering geometry

Fitting up the billet steering arms etc on the brushless car i noticed an improvement to the geometry - less toe in than stock. Transpires the billet arms have an offset sperical bearing, the extra height improved the geometry relative to the bottom arm which sets the steering geometry basically.

Most of you have noticed that the steering toes in as it compresses. Looking at the reason is pretty simple and the cure equally easy. Basically the steering arm needs to be parrellel to the bottom arm over the majority of the suspension arc, if you look front on the steering arm is steeper and as the suspension compresses it pushes the steering arm at the wheel end outwards and creates toe in.

The fix is dead simple, space the steering arm end point upwards at the wheel end and downwards on the steering rack.

The magic number, 2.35mm......... Which was the width of some prop spacers i had ! I think going to 2.5mm sure wouldnt hurt longer cap head bolts needed.

perfect afternoon so took a box of helis to the park - the V930 huey flew beautifully, the XK X110 tail motor and blade worked a treat for the tail hold. HP05C main motor works nice and you can hear the RPM in. overall I calling this a success.

WL V930 chassis, HP05C main motor , XK X110 tail motor / blade and the HK white servos.

So far have found the V930 main rotors to be way nicer than the 966 or 988 blades ? the 966 blades where distorted, different pitch one blade to the other, that took some figuring out....... and very brittle.

next job is to connect the neat LED lights that came in the helimax body.

V930 Huey (3 min 3 sec)

V930 is a powerful brushless FP brother to the popular v977. Had the helimax huey shell for awhile and all but done bar final fit up.

Everything has been a tight fit and allot of lateral thinking to get everything into the front of the huey is an understatement. Lifting the pcb and moving back and cantilevering over the motor and front servo was the defining moment that i knew it would work.

All together today and initially Flying very nicely then all sorts of problems, erratic behavior to say the least, hand holding the unit and wow was there some buzz vibration going on. Long story short pulled the stock motor and in with an hp05c, no more vibes and smooth as....... Was running a 9t on the stock motor but went back to the 8t on the hp05c and let it rev.

Was running the v966 blades, black with green trim but it flew terrible, transpires the pitch is a fraction different one blade to the other, god it was a handfull, so back to the stock blades for now, and smooth as.... will look at the walkera blades in black and green.

Getting 5 minutex on the 520 mah goo, will swap the plug and go for the turnigys.

Job done !

Next job will be plugging up the leds and adding a jst plug for the turnigy batteries. And might see if i can replace the stock Motors bearings....Continue Reading

Since the WL version has turned out to be a dog, have decided to jump in and go brushless on the FY.

the popular 2845 motor and esc kit. Got three motor to test 3100kv / 2800kv and the 2600kv. The 2600 will be 3S

going to start with the 3100 and regear to suit, a massive increase in top speed is not what I'm after, more toque and acceleration = the plan!

Also went with the robertson race 48P - 6 pack of pinion gears, they are nice

opened up the ESC, two boards, going to seal all that up as any water getting in there will then short things out. Heat sink ? has a rubber protection layer on top of the FETs- gotta question how much heat will get transferred like that, I can see heat silicone going in. Also see plenty of silicone around all the wiring soldered joints etc to try and waterproof this.

The front end of the FY has lets us say a bit of float in it....... turns out the front hexs don't sit correctly onto the bearing, the drive pin bottoms in the hex and as a result the hex does not press onto the side of the bearing like it is supposed to = floppy wheels.

the bearings themselves are nothing great, allot of slop as well.

swapped in new bearings and went with a set of HSP pinch mounted hex nuts, this work PERFECT. the HSP drive pin is a fraction larger, I stayed with the FY pins, with the way this hex nut works its not a problem

Use the stock wheel nut and pull the hex down snug, then the pinch bolt locks the hex to the drive shaft, float is all gone. Hex is 1mm wider than stock. the wheels are also a nicer snugger fit onto the hex nut, the outer wheel nut is now just holding the wheel on instead of trying to tension the entire assembly - I'm calling this GOOD to GO

http://www.banggood.com/HSP-Hexagon-...p-1066169.html

Simple maximum rpm test in a stock v977 heli

Stock battery 450 /25c. 4728 rpm

Goo 520 / 30c. 4863 rpm. Straight off the charger !

Turnigy nanotech 600 35c 4822 rpm

Turnigy Graphene 600 65c 4905 rpm

The v977 head is heavily loaded with pitch at maximum throttle, back down the rpm range i was seeing over 5300 rpm from the graphene the motor is absolutely screaming ! The extra c rate is noticable

Graphene is noticably shorter, same length as stock where as the nanotech is the same length as the Goo battery.

Weight

Stock. 12.12g
Goo. 13.52g
Nanotech. 16.13g
Graphene. 15.04g

1/2mm thicker than the nanotechs, trim the raised sections in the battery holder and its a snug fit through the remainder of the battery housing.