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Saito FG-20 or 21

Old 11-06-2017, 07:21 AM
  #1801  
SWORDSN
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I don't have pics,but he is running 20-1 oil and they were both installed in an open cowl,plenty of air ,situation. Both were older engines with many hours of run time.I will post more info as available.
Old 11-08-2017, 04:18 AM
  #1802  
AA5BY
 
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I've now 43 flights (7 hrs) on a Saito 125a converted to gas, using the stock carb. Running 20:1 fuel mix.
Old 11-08-2017, 05:51 AM
  #1803  
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+1
Old 11-08-2017, 06:38 AM
  #1804  
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Originally Posted by AA5BY View Post
I've now 43 flights (7 hrs) on a Saito 125a converted to gas, using the stock carb. Running 20:1 fuel mix.
So you have the glow carb on it, and not having issues with the seals?
Old 11-08-2017, 12:27 PM
  #1805  
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Originally Posted by acdii View Post
So you have the glow carb on it, and not having issues with the seals?
Not so far.
Old 11-08-2017, 01:14 PM
  #1806  
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Been considering adding CH to my 125 in my Mustang, converting to gas without the need for a new carb is a plus. $125 for the 125.
Old 11-09-2017, 07:06 PM
  #1807  
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Originally Posted by acdii View Post
Been considering adding CH to my 125 in my Mustang, converting to gas without the need for a new carb is a plus. $125 for the 125.
The only thing I needed to do beyond installing the ignition is to provide a throttle servo speed slow down.
Old 11-10-2017, 08:02 AM
  #1808  
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I can do that through my radio. Neat trick too, use it for deploying flaps.
Old 11-06-2018, 08:08 AM
  #1809  
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Hello all.Now I have just bought one of these engines brand new but 2nd hand to me(BNIB)I have read nearly every post of the 73 pages and it had made me think.I wonder if running them in on methanol(glow fuel)would help the cooling and running in process.I.E just put a glow plug in and treat like a normal glow running in.I have run in hundreds of glow saito's with no issues and just thought it might help to settle down the engine before running on petrol.I intend to use Mobil 1 2t oil as I have been using it on a converted saito 72A for months now with good results.One other thought,if it does play up big time with spark plugs,ignition..etc.etc..I will just run it on glow forever..I know that is not the point but its my back up plan...What do you guys think?


P.S it was very cheap for BNIB so could spend some more money if required etc..etc..
Old 11-06-2018, 09:39 AM
  #1810  
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Glow would destroy the carburetor. If you keep the ignition system and swap out to a glow carb, then you get more power and better fuel use, but trying to run it as is with a glow plug instead of the ignition will fail .
Old 11-06-2018, 12:58 PM
  #1811  
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Originally Posted by acdii View Post
Glow would destroy the carburetor. If you keep the ignition system and swap out to a glow carb, then you get more power and better fuel use, but trying to run it as is with a glow plug instead of the ignition will fail .
Ok,just wondered what the carb(diaphragm etc) was made of you see.If it was unaffected by methanol then it might work as the needles are still too sensitive ,even when supposed to be designed for petrol..weird really for Saito to do that.Yes I have read somewhere that you can run on glow with the spark plug and timing stuff on and it gives 5% more power,Ironically. ..That would be nice.As i said earlier I have converted a Saito 72a to petrol and its rips around in a Kyosho Calmato lowinger.It gives nearly 1.1HP instead of 1.2,or at least over 1hp so like a saito 62 really.All i did was make a gasket of about 0.4mm to put under the head and change the spray bar and needle valve to whats in a saito 14c and it tunes very well.Idles at 2200 and gives about 10200 on a 12.5x6 Bolly prop.Obviously its got a RCEXL ignition system and magnet ring/pickup etc..etc.. I have a saito 14c and fg-11,I have run the 14c and it goes well once I had re-learned the tuning for their petrol's as i learned from re- building the carb on the 72a that the idle needle drastically affects the top end tune at all times as the idle needle still covers the split in the spray bar where the fuel comes out of into the intake manifold.Once I had got this then the 14c purred like a kitten.I am ready to give the fg-20 a go but just got all sweaty from reading here!Maybe I should not have bothered reading and just done it.I have checked,my fg-20 has a new type spark plug in with no label,and a small center punch dot on the carb behind the fuel intake ,not where it shows on the pics here but maybe they put them in a few places..I hope so.

If the ignition plays up then i will get the RCEXL setup like on my 72A but I understand the hall sensor setup for the fg-20 has an offset sensor to allow for the 28deg timing BTDC that the RCEXL unit uses,unlike the original saito big bulky sensor...if I have read correctly.And if the carb fails I might get a proper petrol one ,or glow one and run it on glow...For the financially interested, i paid 145 for it, so about $188 for a BNIB Saito FG-20....we will see,fingers crossed....FG
Old 11-07-2018, 02:15 AM
  #1812  
forrest gump
 
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So my main question is Why cant we use glow fuel on the saito petrol carb?When using tubing and tank bungs suitable for Petrol fuel ,you can use glow fuel on those with no issues.It usually only works one way round..don't use petrol on stuff made for glow...that's my point really...Does anyone definitely know what's in the saito petrol carb and whether glow fuel will kill it or not??

Last edited by forrest gump; 11-07-2018 at 02:16 AM. Reason: spelling
Old 01-20-2020, 11:07 PM
  #1813  
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Hello,
I am wondering is it safe to run gf21 with straight stock pipe only, no bulky can muffler Part installed?
Since i fly the ngh38 4stroke and it is mentioned in Manual that with short straight pipe it gives more power and runs happier.

What about fg21?
no noise restriction problem

Thanks
Old 01-21-2020, 05:58 AM
  #1814  
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Sure, just tune for it.
Old 01-25-2020, 12:27 AM
  #1815  
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Thnx will try then and report

Received it at last.
Spark gap was double than spec, fixed, now it fires a much nicer arc.

Ignition is an rxcel one which is great,
no need for upgrade as I have seen some have done with old saito one to fix some problems...





before


after



And valve clearances were none, 0.
Tuned them but did also experience the needles falling out from rocker seats, as some have reported here.
Sure hope valves/springs wont float during operation since that may force needles to fall out (seat disengages from needle since spring is not putting pressure on it)










Last edited by dr.tom; 01-25-2020 at 07:31 AM.
Old 01-27-2020, 01:16 PM
  #1816  
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Works like Saito should work,
Flipped it a few times in reverse to prime it and it came alive.
Valve clearance are supposed to be 0, so adjusted them back to stock before starting.

Hand start, first run ever.

https://youtu.be/aTnkCfMrKE4







Last edited by dr.tom; 01-28-2020 at 10:34 AM.

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