Hi there!,
I have a saito FG 30,I had it from new, is being bench tested tunned and runned in,using 20-1 amsoil dominator oil
http://www.youtube.com/watch?v=r4kaiM2vhYc
it started very easy,no ptoblems at all, setted high end for max rpm then opened a bit ,the low end needle for a smooth idle and quick pickup,all was looking good!.
Then I fitted the engine to a Goldwings 30cc 73" MX2 very light and nice plane, had to cut the firewal back and reinfroce it because the engine is quite long, so after this got all ready, took off and no trim needed at all, very smooth fast and accurate to fly,didn't want to abuse the engine so just tryed to hover and was doing it at 1/2 stick and pulling out vertical very fast, pleased with the whole setup.
So here is the problem, noticed on take off was hesitating on full throttle when speeding up (the patch Ifly is very short) and loosing a bit of power for a split second then ok, also when flying straight and going very quick to a nife edge (on the left side) the same hesitating and losing power a bit then ok.
Didn't bother me because I knew the engine still new,but know having a good 20 flights, last weekend spent lots of time trying to sort this out with no succes, ovious thing to do is get the low end richer Idid also the high end. still doing the same, only getting rougher running, and it was misfiring a bit on the middle stick at level fly, Itried all the possible neddles combinations, same resault , that hesitation
allways there,sparkplug is new,checked no much carbon just a nice mushrom grey colour.
Had a dubro Easy fill valve Ioverrided just in case,changed the fuel lines for bigger ones ,and I done the plumbing dead straigth from the tank to the carb,going just trough a filter,tank is close anyway. (also changed the clunk and clunk line)
Im a car mechanic and im being playing with engines since my 13s, so my ears are well used to a well tunned engine!,
so my guess is, Ibelive this engine has a walbro type carb,but with a barrel like the glow ones, also Ithink they dont use a diaphragm pump system due the lack of back pressure being a 4st, so my guess is they are using an ocsillating one, which it might not work properly at high g forces manouvers, the actual ballbearing inside might just stop or slowtoo muchfor asplit of second when the airplane rotates too fast in the same direction, drooping the fuel pressure a bit.
If you fly normally, just scale aerobatics is just fine,but if you put the sticks in the corners, it will do it then is ok,when going quick to knife edge it does but then goes ok you can do figure 8 knife edge circuits through the whole tank! is just the very quick change of direction which affects the engine.
So my other plane is a 63"sukhoi with a cheap crrc pro 2st 26cc, a bit less power ,but once riched the sweet spot never gave me a trouble,dont miss a single beat using just a chanisaw walbro carb!,so If this saito is more suitable for scale, war bird aircrafts, I might sell it and buy a JC28cc or dle 30cc for less money, SAito sounds awsome! but is much heavy 400g more up front ,wings rocks a lot and is hard to keep a harrier stright and ifI cant sort this problem will be betteron ascale plane instead!!
Any ideas
Thanks!!
Luis