600/OS55 Cutting Inverted

[Nick B]

Sorry it broke Dave,how long has the 55 been running with the pipe?

I take it that it never used to cut?

[waveydavey]

It's been doing it since I put it the engine in really, I've just been lucky enough that It's been recoverable until yesterday, previously it just seemed to be when I was inverted. It's not that bad as damage goes just seems like I'm not going to get to the bottom of it without a bit of risk. The engine has had around 4.5 gallons through it and I love it just not the cutting out

[coolice]

Ian I have got another pipe but it's just the standard align 50 one, Pete runs the same combo, the reason I went for it really. I do think it sounds like tuning now just wish I done it before writing it off yesterday.

Thing is I've lost so much confidence in it how do I test it, lots of height and hope for the chance to get it down in one piece I suppose

Hey matey.

If all else fails tuning wise it certainly might be a good idea to try the Align muffler, again its not ideal for the 55 I'm sure but the tuning will be different to try and eliminate a possible cause.
Squeaky's got the same combo but what ratio does the ElyQ run over the 600? I wouldn't imagine its far off but if its different it will effect things, so to will tank location within the model to engine.

I did hear you'd paid a visit to the gun club heli pad ;-/
There's not much else for it but keep trying, unless someone had head leaders as a basic test? I know what you mean about confidence in the model being lost, your always on edge waiting for it to stop.

It's got to be something really silly as the majority of the flight its ok but just inverted and unloaded from what I'm gathering.
We'll all have to have a go sorting it.
.

[coolice]

Just checked Vision 50 is 8.72:1 and trex is 8.5:1 so the motor is reving higher in the ElyQ for a given motor rpm.

Squeeky what HS you running? Perhaps we could try and match it on Dave's.
.

[waveydavey]

Cheers Ian, the lads in the gun club were in too, oops! Optifuel use the same combo for testing too so I don't think it's the engine and pipe, maybe just the tuning as Andy said yesterday. I'll see what Saturday brings, get it back together, my current TT muffler is a bit bent but I've just bought a new one off Russ so I'll test it with the old one before going for the new one I think. Just in case if you know what I mean. The ely Q is 8.7:1 compared to 8.5:1 for the 600. Why would this make a difference?

[coolice]

Hey.

With the ratio difference on the ElyQ running 2k on the head the engine will be reving higher than the same engine running 2k in the trex.
I don't know off the top of my head what the optimum rpm of the 55 is to work out from the gear ratio what head speed you need to be at ideally to get max power, have to Google.

It does seem strange the problems but it sounds like it might be getting worse as you go along, is it getting more frequent? It's not impossible the pipe is blocked or a baffle had moved altering things.

Put it all back together and perhaps if we all put our heads together we'll sort it.
.

[squeaky pete]

i havent got a clue what headspeed im running, im not using a gov on the model, just flying curves, giv me 5mins and ill check my needles and my thottle curves

and u want to be aiming for about 17500rpm on the engine so u fall in the power band

[waveydavey]

17500 would give me 2050 on the head and I run 2070 so if I bog it with my bif Geordie thumbs it drops into it's normal range.

Pete what are your needles set at.

Ian I don't know if it's getting worse just seems to be since I started to lean it in.

[squeaky pete]

right, now shes off the fone i can go check, and i ment 17750 lol was on the fone when i rote that lol

[squeaky pete]

right, my idle needle is almost hoizonital, between 2 and 3 oclock, the top needle is about 1 and a 1/4 and the mid is 1 1/4 aswell, and a os8 plug for what its worth

and my idle 2 thottle curve is 100-62-100 and exp on

[squeaky pete]

must add aswell, ive got 15% thottle to ali and thottle to eli mixes

[Cuppa]

Yep yep n yep been down those paths when my YS56sr
did that to me a few times, new pants please lol.
ternd out to be a winter time fuel boggy!
as i think most of us fly far less in the winter (heli layd up more)
any fuel residue left in the carb system will become 'snotty'
Drain tank and flush, change fuel lines (thay get sticky at shut off points,
if you use a fuel magnet or the like change the eliment,remove jet needles
and gently blow it through with something like Wynns carb spray cleaner
then run at a richer setting, 1/4turn do a tank nowt clever!
then re tune all being well, outsid that ask someone who knows


Air thicker, use more fuel,thinner Air less, colder the thicker.

[squeaky pete]

1 and a 1/4 on each needle lol not a 1/4 lol

[Cuppa]

Fair play pete 1 1/4 how about nitro% i run 30 in my 6&700
ys56sr and os hz91-r

[squeaky pete]

oh yes, 30% nitro, rapicon, mine starts 1st time, lumpyish idle, but once up to speed its a power house