(220) FRP porting effect on jetting?

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JZ05220r
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(220) FRP porting effect on jetting?

Post by JZ05220r »

First off, I found that my right side crank seal is leaking because my trans oil level is dropping. Sometimes it smokes way to much and it’s just not that sweet premix burning smell. I have posted about a bog when twisting the throttle quickly at idle speed in gear and noted that the engine smokes a bunch as this happens. It ranged from a full on bog to what I’d call “almost bogging”. Since June(rebuild) I have been struggling to get it jetted correctly. Not sure if it the crank seal or carb jetting but I wanted to hear what others have found jetting wise when going from the stock 220 porting to FRP. With it being a pain to get in touch with Jeff Fredette about this, I’ll ask you all here. Thank you.
2005 KDX220r 1991 KDX200 2022 KTM 500excf
JZ05220r
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Re: (220) FRP porting effect on jetting?

Post by JZ05220r »

JZ05220r wrote: 08:01 pm Nov 03 2022 First off, I found that my right side crank seal is leaking because my trans oil level is dropping. Sometimes it smokes way to much and it’s just not that sweet premix burning smell. I have posted about a bog when twisting the throttle quickly at idle speed in gear and noted that the engine smokes a bunch as this happens. It ranged from a full on bog to what I’d call “almost bogging”. Since June(rebuild) I have been struggling to get it jetted correctly. Not sure if its the crank seal or carb jetting causing this headache but I wanted to hear what others have found jetting wise when going from the stock 220 porting to FRP. With it being a pain to get in touch with Jeff Fredette about this, I’ll ask you all here. Thank you.
2005 KDX220r 1991 KDX200 2022 KTM 500excf
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Molly's 70
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Re: (220) FRP porting effect on jetting?

Post by Molly's 70 »

I didn't have to change anything jetting wise. I just checked my pilot/air screw to make sure. I'm still a tad rich on the main jet. Plug looks really good.
If you lend someone $20, and never see that person again, it was probably worth it.
JZ05220r
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Re: (220) FRP porting effect on jetting?

Post by JZ05220r »

Molly's 70 wrote: 04:28 am Nov 04 2022 I didn't have to change anything jetting wise. I just checked my pilot/air screw to make sure. I'm still a tad rich on the main jet. Plug looks really good.
Gotcha. It seems that the bigger carb size to support the porting makes the biggest difference in jetting. I’m guessing you have a 35/36 mm carb. Thanks
2005 KDX220r 1991 KDX200 2022 KTM 500excf
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Re: (220) FRP porting effect on jetting?

Post by Molly's 70 »

It's a 36mm RB carb.
If you lend someone $20, and never see that person again, it was probably worth it.
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