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Discussion Starter #1
I see on a previous post about plugging the air jet. Question is which one is it and do I need to do it with my setup. Cobra Drags, carb mounted air filter and Dynojet kit installed.

Reason I ask is I have never been happy with my setup. If I run with full air flow through the filter I get lots of hesitation and stumble around mid to high end regardless of jet size, needle height and/or mixture adjustment. My solution is to restrict the air flow through the filter (read duct tape) to the approximate volume of the original setup and go back with stock needle, jet and adjustment. Runs OK but I feel like it could be better and it

Just Ain't Right.

And OH Yeah those screws are locked in GOOD!


 

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I assume you've tried the setup from the matrix (usually pretty close to perfect).
Aftermarket or stock pipes (baffles or debaffled) & Uni filter or K&N (airbox mounted):
150 or 155 main, 37.5 pilot jet, dyno spring, dyno needle on 3rd notch, mix screw at 2.5 - 3 turns. Adjust idle knob as needed to reach 1100 rpm.

I am fairly sure the jet is #3, although I plugged mine 4yrs ago with the bell on so I could be wrong) - Hurricane setup. Plug it temp with something and see if it helps. From your description I would suspect the main jet
The pilot controls idle, up to 1/3 throttle.
The needle controls 1/3 to 5/8 throttle
The main jet controls the rest


Two other common things come to mind, you've probably already checked them but I'll ask anyway.....

1 the needle needs to pop/snap in place when you put it back in. If you look at it on page 15 of Briman rejet instructions you'll see an oring around it that needs to pop/snap back in when reassembled.

2 the tiny little o-ring that 25% of the people loose, which is shown on page 13 in Briman's instructions.
 

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Yup...number 3

and yes I think you should with your set up off a high flow air filter and exhaust with the larger jets and needle.
 

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Discussion Starter #4
Yep, I pretty much followed the matrix exactly to begin with. Then varied with needle position and mixture adjustment . Mileage also dropped off like a rock. 160 was really bad got better the smaller I went and finally put the 132.5 back in. Then still had some stumble so I put the stock needle back also.

I did not replace the pilot as I did not have one but it has always run good at the low end and up through about the first half of the middle.

I can't help but think I've missed something but this is a good forum and I have yet to find anything I might have missed until the post about the Air Jet and that was under a Thunder Mfg. topic (http://www.volusiariders.com/viewtopic.php?t=91520}

I've had the carb off so much I can do it blind folded I think..

I did feel the pop and the oring is in place.

I'll tackle it again this week sometime and cross my fingers. Thanks

Ride Safe. Have Fun.
 

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Where ya located..... Sometimes another set of eyes is good....
 

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Aftermarket or stock pipes (baffles or debaffled) & K&N (carb mount):
155 or 160 main jet, 40 pilot jet, dyno spring, dyno needle on 3rd notch, mix screw at 2.5 - 3 turns. Adjust idle knob as needed to reach 1100 rpm.

I've found the pilot jet is the key to getting it all just right. I think stock is 32.5, way small for a Uni.
 

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Discussion Starter #8
Like many with the Dynojet kit, I have not changed the pilot jet. If it affects idle and low end why would changing it affect the high end.
 

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Discussion Starter #10
Not trying to be argumentative...to be honest...as much as I have read here and there about jetting I should have already changed the pilot. I didn't because the Dyno kit doesn't come with one. That I guess led me to think it wasn't necessary. I'll go get a few...37.5 and 40... today ,I hope.

Thanks
 

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Discussion Starter #11
ALRIGHTY Now...160 Main, 28.5 pilot(stock), 2.5 turns on the mixture and needle at 3rd or middle position. I also plugged the air jet. Before There was a LOT of stutter and hesitation on the top, NOW with the air jet plugged....Well all I can say is what a difference.


Should this not be in the matrix?
 

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Hi guys,
What does it help for to plug that air jet?
I have Cobra Drag pipes installed with everything else being stock.
 
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