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Is it common to have to change the pilot jet when installing a flex jet?

 

I installed one and when I tried to adjust it I found that I could turn it all the way in and the bike still ran, roughly, but it ran.

 

I installed one size smaller (42) and It ran best when turned all the way in.

 

Installed a 40 and now it runs best when about 3/4 to 1 turn out but doesn't die when turned all the way in.

 

Am I where I want to be or do I need to try the next smaller jet size?

 

Thanks

RM14

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Did you first lower the idle speed? If not, you could be slightly on the needle and that will give you poor adjustment. Also, if you have a E with the coast enricher, if it is not working oer removedimporperly, it too, will mess up the pilot/fuel screw.


Flex Jet is supposed to be identical to an OEM screw and should not require a different pilot.


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Did you first lower the idle speed? If not, you could be slightly on the needle and that will give you poor adjustment. Also, if you have a E with the coast enricher, if it is not working oer removedimporperly, it too, will mess up the pilot/fuel screw.

Flex Jet is supposed to be identical to an OEM screw and should not require a different pilot.

 

 

+1.....which model fcr did you install it on...?...

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The carb is an fcr mx got it new from Eddie/Epic 9 months ago or so. Its on a 2011 S model, stock engine.  San Francisco bay area, 50 to 3849 feet.(summit of Mt. Diablo)

 

The flex jet came with washer, spring, O ring. I used what it came with.  Would the bits off of the other fuel screw make a difference?

 

I was surprised I had to change the pilot jet, twice no less. I'm getting good at the carb removal/installation dance.

 

Thanks to you guys for the help. For me and thousands of others.

 

RM14

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When you removed the stock fuel screw, you did remove the oring/washer and spring? Nothing left behind?

 

No need to remove the carb to swap pilot jet. It is a five minute job on the bike.

 

SSW FCR should need the 45. You must have the idle speed way too high when setting the fuel screw. With the bike hot, slow the idle down to where it will just run. THEN adjust the fuel screw for the fastest speed. Slow the idle speed again if needed. Once you find the best idle based on the slowest speed and optimum fuel screw setting, close the fuel screw, trackign carefully how much you have to turn it to gently closed. If the bike only stalls at 1/2 or just closed, the ilot jet is right. Reset according to the optimum setting. If you have to open the screw more then 2 turns, try the next larger pilot.

 

I thinki you are going to discover, a 45 pilot at abount 1.5 turns for you is actually correct.

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Correct, nothing left behind.

 

I'll try what you suggest.

 

As far as removing the jet, I assume you are talking about rotating the carb after loosening the clamps.

 

I can't get it to rotate, the throttle wheel hits the frame.  Any suggestions?

 

Thanks again

RM14

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I got a R&D Flex Jet off TT this month. It's given me nothing but problems. I think I FINALLY have it sorted out. I too have a 39mm FCR set up by Eddie. I ended up swapping the flex jet spring, washer, and o-ring with what came off the FCR fuel screw. I noticed the o-ring on the flex jet is smaller than FCR stock. My flex jet wasn't holding a setting. I'd go 1.5 turns out and after a ride it's 4 turns out, bike floods, and I had trouble getting a restart. I lubed the cable and knob/bracket with teflon wax because I think it was binding and unwinding if that is possible.

 

When it kept slipping 4 turns out it caused me to foul a plug. I needed a tow a couple weeks ago at the beginning of a group ride. I didn't have an allen key on me to drain the float or a back up spark plug. I found the only way I could get a restart was to shut off the gas and hold the throttle wide open. If that didn't work drain the excess gas in the float bowl and repeat. Yesterday I needed a push start to jump the bike on the backside of Mt. Hamilton down on Del Puerto. I'm 1 & 1/4 turn out and didn't have any problems for the remainder of the day. The bike idles high when hot, but comes down nicely when it cools off a little and starts on the first try with no throttle. The idle setting and the fuel screw setting are really sensitive. Mine won't die instantly when I turn the fuel screw all the way in. If I leave it there it will choke itself.

 

Hopefully it's settled now. Wondering if your bike will start every time you shut it off, even seconds after coming off a freeway and shutting it off, really sucks the big one.

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I don't have many miles with the flex jet. Just a few laps around the neighborhood to warm it up.

It starts fine as of now.

 

RM14

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It took me over 400 miles to sort mine out, because I didn't understand what the problem was the first time, the second time, the THIRD TIME.

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Quick question -Will the flex jet fit a non MX FCR, i.e. the one on an aussie E after drilling out the bowl hole?

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Quick question -Will the flex jet fit a non MX FCR, i.e. the one on an aussie E after drilling out the bowl hole?

 

YES it will fit the FCR slant body,not sure why people keep saying it doesn't. drill out the bowl with a 6mm drill bit, i have found it best not to attach the brass knob to the float bowl,it sits hard up against the start motor otherwise and is really difficult to turn

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