Setting the Fuel Mixture Screw?

hey guys.
i need a bit of help setting my fuel mixture screw on my KTM 450 EXC 2004 model.
ive currently got it 2.5 turns out from closed. i think it might be a little rich, however the only symptoms i had of it being too rich, is that i barely need to use choke to start the bike up; i only need to use choke for a few seconds.

the bike isn't hard to start at all when hot and there are no other symptoms to suggest that im running too rich.
the reason why i think i might be running rich is because others have said that anymore than 2.5 turns out means i need a bigger pilot jet.

all my jets are stock, as per the manual and recommended by various KTM dealerships around my area. I am not interested in purchasing a JD Jet kit just in case anyone was going to suggest that.

I tuned the carby as per the manual, by setting it at the basic/factory setting of 1.25 turns out then turning the mixture screw in(clockwise) until idle decreased, then back out(anti clockwise), until the bike started to die again......then set it at the highest point between these 2 points which was 2 - 2.5 turns out from closed(the idle didn't change between these marks), so i set it to the 2.5 turn mark as i thought its better to run richer than it is to run leaner.

the current set up is:
main: 178(stock)
needle: OBDTR on the 4th clip(stock)
pilot jet/idle jet: 45(stock)
starting jet: 85(stock)
Mixture Screw: 2.5 turns out from closed
Float Height is set to stock height of 2.5mm

all stock jetting.
im just wondering what others recommend the fuel screw setting should be(roughly) or what others have it set to on their bikes, preferably from KTM RFS owners.

at the moment its spring season down here where i live, average temperature of 15 degrees Celsius(59 degrees Fahrenheit)..and cold, but during summer time it gets up to 35-40 degrees Celsius(104 degrees Fahrenheit) on average.
 
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Ok cool. Thanks mate :)
Question though, it's a 4 stroke, so if I happen to run it slightly too lean, will it have any negative affects or do engine damage?
Just wondering out of curiosity, cos I know on 2 stokes it can do damage if its too lean.
 
it is pretty hard to hurt either one with the low speed settings unless your high speed settings are already on the dangerous side. try tuning it to the suggestions in the manual and see if it ends up being leaner when done the factory way would be where I would start. there is nothing wrong with having a screw set out further than what is recommended as long as it will stay in place and in adjustment. after about two to two and a half turns, most are candidates for being lost though.
 
hey guys.
i need a bit of help setting my fuel mixture screw on my KTM 450 EXC 2004 model.
ive currently got it 2.5 turns out from closed. i think it might be a little rich, however the only symptoms i had of it being too rich, is that i barely need to use choke to start the bike up; i only need to use choke for a few seconds.

the bike isn't hard to start at all when hot and there are no other symptoms to suggest that im running too rich.
the reason why i think i might be running rich is because others have said that anymore than 2.5 turns out means i need a bigger pilot jet.

all my jets are stock, as per the manual and recommended by various KTM dealerships around my area. I am not interested in purchasing a JD Jet kit just in case anyone was going to suggest that.

I tuned the carby as per the manual, by setting it at the basic/factory setting of 1.25 turns out then turning the mixture screw in(clockwise) until idle decreased, then back out(anti clockwise), until the bike started to die again......then set it at the highest point between these 2 points which was 2 - 2.5 turns out from closed(the idle didn't change between these marks), so i set it to the 2.5 turn mark as i thought its better to run richer than it is to run leaner.

the current set up is:
main: 178(stock)
needle: OBDTR on the 4th clip(stock)
pilot jet/idle jet: 45(stock)
starting jet: 85(stock)
Mixture Screw: 2.5 turns out from closed
Float Height is set to stock height of 2.5mm

all stock jetting.
im just wondering what others recommend the fuel screw setting should be(roughly) or what others have it set to on their bikes, preferably from KTM RFS owners.

at the moment its spring season down here where i live, average temperature of 15 degrees Celsius(59 degrees Fahrenheit)..and cold, but during summer time it gets up to 35-40 degrees Celsius(104 degrees Fahrenheit) on average.

sounds like your pretty close, but as far as the choke goes....i only use it to start cold and run for the first few seconds myself, then dont use it again till the motor has been shut down for a couple hours, and by the way 59 degrees F is not cold in my opinion.
 
Most two strokes are jetted a little rich for me on the low end. If the enrichenor isn't needed for long, we are all giving up some hp (small amount really) at the higher revs. Road racers and flat track bikes alike used to be push started almost exclusively. One reason was a weight savings, but many of the flattrackers retained the kick start anyway (TT races in particular had stalls and slideouts that could be overcome and points salvaged). One of the reasons for the push starts by the guys who were fastest (Kenny Roberts, Gary Scott, Hank Scott, Keith Mashburn etc) was because they were jetted so lean that the riders would get tired kicking them and from their dad's to the mechanics it was easier to just push them. Those critters ran some pretty oil rich mixes, had electrics that weren't at all like today's (points in many cases) and lots of times had little for brakes. So slowing with a compression release and the motor was common then. So were fouled plugs if yours was an easy starter.

For those guys the extra .75 hp plus the reduced chance of fouling or nearly fouling was a pretty strong motivator.
 
2.25 turns out seems to be the sweet spot for my bike. i set the idle to within spec(1500 RPM).
at 2 turns out the idle dropped a bit(down to 1430), at 2.25 turns out the idle rose to 1550 and at 2.5 turns out the idle dropped again to 1455-1470).

is 2.25 turns out okay?
 
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2.25 turns out seems to be the sweet spot for my bike.
2 turns out the idle dropped a bit(down to 1430), at 2.25 turns out the idle rose to 1550 and at 2.5 turns out the idle dropped again to 1455).

is 2.25 turns out okay?
For me I usually go to best idle and back down maybe 1/4 turn. Seems to be a decent rule of thumb for me.
 
I set my idle a little higher to the 1800rpm range to help with the accidental stalling and to not have as much off throttle engine braking..the pilot and FS settings are fine///I would re-jet tho and do the AP o-ring mod and diaphram to make it run better.
 
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