rich fcr,s
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- steve speed
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rich fcr,s
can any one give me a clew as to why my fcr41s run rich at 2000rpm its ony at that revs it dose it i have adjusted the slow air screw and the fuel screw ,its ok every were else its just goes rich at 2000 rpm (i have no tps ) any ideas ????
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- honkdawillydahonk
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Re: rich fcr,s
2000RPM? Do you use that part of the rev range much then?
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- steve speed
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- honkdawillydahonk
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Re: rich fcr,s
steve speed wrote:No i don't but it bugs me that it does it![]()
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- Killerwhale
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Re: rich fcr,s
I went down one size on the slow jet and upped the fuel screws, helped me anyway.....in polarbear country....steve speed wrote:can any one give me a clew as to why my fcr41s run rich at 2000rpm its ony at that revs it dose it i have adjusted the slow air screw and the fuel screw ,its ok every were else its just goes rich at 2000 rpm (i have no tps ) any ideas ????
- steve speed
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Re: rich fcr,s
went down one size on slow jet , its better but not right so i will give 40s a try and if its still rich it has to be the needle jet , , yes they do ware out , it runs ok on tick over then it hits 2000rpm and its like the choke has come on, it then clears its throat by 3000 rpm and run sweet
(needle jets are not cheap) bugger

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Re: rich fcr,s
How many turns on the fuel screws??steve speed wrote:went down one size on slow jet , its better but not right so i will give 40s a try and if its still rich it has to be the needle jet , , yes they do ware out , it runs ok on tick over then it hits 2000rpm and its like the choke has come on, it then clears its throat by 3000 rpm and run sweet![]()
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(needle jets are not cheap) bugger
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- steve speed
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Re: rich fcr,s
one turn on fuel screw but when i tried them at half a turn it was not right on tickover and was still as rich at 2000rpm slow air is at 1.5 turns, its looking more like needle jets the more i think of it and as steve at alans said its the only thing it can be now ,,,,I WILL HAVE IT RIGHT

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Re: rich fcr,s
If under 1 turn out...smaller slow jet and same on top IIRC...steve speed wrote:one turn on fuel screw but when i tried them at half a turn it was not right on tickover and was still as rich at 2000rpm slow air is at 1.5 turns, its looking more like needle jets the more i think of it and as steve at alans said its the only thing it can be now ,,,,I WILL HAVE IT RIGHT![]()
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Mine where better when i locked the AccPump arm so it don´t rely on the spring....might add that i use the boyesen quick shot though.
...also, mine has a REALLY nasty lean spike at 3k....see pic:

- steve speed
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Re: rich fcr,s
$81us a bit expensive ,,,,well i tried 40s slow jet and it was rubbish so i have new needles and now on there way is new needle jets we will see tomorrow what happens
TRX850 ,The thinking mans R1
- steve speed
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Re: rich fcr,s
new needle jets,, new needles this time the right ones OCEMP not T ,,48 slow jet ,gone down on main jet to 165 but fitted smaller main air jet 180 runs a LOT better on the stand i will give it a test ride once it stops persisting down

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- steve speed
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Re: rich fcr,s
Wonder why you don´t have the standard MAJ in yours?steve speed wrote:runs a lot better at WOT with 180 maj in ,,,,dyno time
- steve speed
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Re: rich fcr,s
the 200 maj was just making it go lean at wot,, it was ok up to 8000 rpm then it would start to go lean ,so this points to the maj is too big ,,,i think !
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Re: rich fcr,s
There you go how different they are, mine goes fat on the top!steve speed wrote:the 200 maj was just making it go lean at wot,, it was ok up to 8000 rpm then it would start to go lean ,so this points to the maj is too big ,,,i think !
....not that it matters much coz then i´m already over max HP...