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New MRD Z Pro, threw off jetting

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My beautiful Z Pro showed up in the mail today! Man this thing is LOUD! I love it. Although the increase in flow really threw off my jetting big time on the pilot. Fuel screw adjustment.. not good enough. Really reeks of fuel at idle. Running a 45 pilot currently. Big bog on a quick snap. Wont hold steady idle. Fuel screw all the way in and idle raises. Fuel screw 3 turns out and then sutters and dies. Should I be moving up or down on pilot? 42 or 47? I have both sitting on the bench. 

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EDIT: also I duct taped the airbox since the previous owner thought it would be clever to drill 6 1" holes on the side cover. I'm sure that is a factor as well. 

Edited by Methotic

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The pilots follow a 0 2 5 8 progression, not sure where you got a 7?

When you turn the idle screw in and the rpms rise what happens if you turn the idle back down to normal and try tuning again?

What needle are you using and what displacement is the engine?

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1 minute ago, ohiodrz400sm said:

The pilots follow a 0 2 5 8 progression, not sure where you got a 7?

When you turn the idle screw in and the rpms rise what happens if you turn the idle back down to normal and try tuning again?

What needle are you using and what displacement is the engine?

Sorry, you are right. It's a 48 not a 47. Screw all the way in seems pretty smooth. 440 bore and EMN needle 4th clip. Fcr41 

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What pipe is it replacing? Stock? I didn't have to change jetting from my fmf to mrd.  They are indeed a beautiful pipe!

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10 hours ago, Scottg07 said:

What pipe is it replacing? Stock? I didn't have to change jetting from my fmf to mrd.  They are indeed a beautiful pipe!

No, it replaced a FMF powerbomb and spark arrestor. I also patched up air box.

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14 hours ago, Methotic said:

Sorry, you are right. It's a 48 not a 47. Screw all the way in seems pretty smooth. 440 bore and EMN needle 4th clip. Fcr41 

What idle air jet are you running? 

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9 hours ago, ohiodrz400sm said:

You need to get an R diameter needle

I checked needle, cant remember which one I ordered. Turns out it is in fact EMR, not EMN. My mistake. 

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1 hour ago, bumtarder said:

So it's too rich with a EMR needle and a 42 pilot jet?

 

I'd also untape those airbox holes too and take it for a blast up a hill and see how it pulls.

 

 

May have to try that. Btw it's running a 45 pilot. Had it running pretty solid until I taped the holes on the airbox and put the MRD on. Only reason why I taped it to begin with is because when I got the bike the top end was destroyed by sand and dirt that nust have got in through the airbox. Had to replace the cylinder and piston. 

Edited by Methotic

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I did some late night tuning last night. I decided to move down on main jet since I've always had a mid to top range bog pulling from low RPM. Went from a 178 to 165 main jet. That helped get rid of most of the saturated bog. The exhaust note is more crisp and responsive now. Also I swapped the 45 pilot for a 42. Seems to idle pretty good now. Although it's probably not the perfect setup, its pretty close. Without a wide band, all carb adjustments are pretty much throwing pasta on the wall and hope it sticks...

Currently FCR41mx

Main jet: 165 

Pilot jet: 42

Fuel screw: 1.5-2 turns out

Needle: EMR

Leak jet: 35 (might have room for improvement) THOUGHTS??

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1 hour ago, Methotic said:

Came across a engine part out. Scored on a set of Stage 2 Hotcams. Look to be in good condition. For $130 shipped can't complain!

FB_IMG_1570200047706.jpg

FB_IMG_1570200040445.jpg

Good score!

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23 hours ago, Scottg07 said:

Good score!

indeed. I ordered a new Wiseco cam chain as well. Should arrive with the cams on Monday. 12K miles on the bike so could use a replacement. I should probably rebuild the head with Ferrea valves too, although that gets expensive fairly quick. A job for another day I suppose. 

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