Too rich or too lean ??

[sharky]

Need a bit of help here:(]...Rev the engine to 3000+ and shut off...revs drop to around 2000 and then drops slowly to around 1000, splutters and then dies. I've tried going rich and lean on the screw (3 full turns is stock, Dynojet kit for bike said 5 turns).
It was a lot worse with the open end can as opposed to the supertrapp discs so they have gone back in. This improved it a bit but not yet right.
I'm running 2 dual outlet K&N's for an Fj12. Above 3k it revs clean and strong. I'm thinking to go up one size on the pilot jet ?????

[Booster]

See if some choke helps or makes it worse?

[TurboKat]

Sounds like a vacuum leak or fuel blockage Sharky, check your carb-manifold & manifold-head sealing & also check for blocked idle circuits or pilot jets, both can cause symptoms like you mention.

[xjrjack01]

Yep could be vac leak or fuel problem, but just out of interest what other mods have you done to run individual filters? And when you say "Rev the engine to 3000+ and shut off" do you mean turn off ignition or close throttle?

[sharky]

Booster,Adding choke made it worse. Reset mixture screws to 3 turns out and it was better but not right...ran worse up to 3k.
Xjrjack, I meant just revving it to 3k and above and closing the throttle.
So carbs stripped and cleaned. The shop suggested it might be simple thing like having the muffler straight off the collector with no link pipe so I have now added 12" of pipe and will test it tomoro.

[xjrjack01]

I think that screw on top that you can adjust is an idle air screw and has little effect on making the bike richer or leaner. Remember also that the numbers on the jets you get with a dynojet kit do not compare to the normal jets used. What I mean to say is a #115 normal jet will be a different sized jet to a #115 dynojet, I don't know why they have their own different size chart but they do.Also have you advanced your igition I know you can safely advance 4 degrees with an xjr motor, knot sure but yours may be different. From what your saying I think your problems have more to do with fueling than exhaust but hey try the pipe and see how you go. But if I were you and had the money I would get the bike on a dyno and see what the fuel is really doing.

[sharky]

The screw is the pilot (idle) mixture screw and it is only effective in the low rev range (pilot jet circuit) to around 3000 normally. Over that your on to main jet.
The jet kit said to take the screw out to 5 turns (richer) from the 3 turns stock. According to the kit I can get all the adjustment I need from the parts supplied so I am reluctant to increase the pilot jet size. Fingers crossed the pipe mod works. It sounds logical as before I changed from stock/modified mufflers it was fine and I know pipe length has a lot to do with engine characteristics.:D
I'm just trying to get it as close as before I head to the dyno.

[unsane]

Also try checking the simple stuff dude. Try messing with the throttle cable adjustments, ive had similar probs before from the cables being adjusted bad after pulling carbs of removing right switches. Either that or air leaks.

[Booster]

If choke made it worse then your too rich , put your idle screws back for best idle/part throttle and drop the needle one groove.

[sharky]

Adding the 12" of pipe helped...and choke killed it. Screws back at 3 turns out...time for a test ride.

[xjrjack01]

Try screws 1 1/2 - 2 turns out and lower the needles, if they're the same as mine there will be 3 grooves for the c clip to go on. My 1300 seems to run sweet with the needles on the second groove and #112.5 main jets, but then again I'm still running an air box.