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Discussion Starter #1
sea level RKT head with a MBRP performance can. clutching dialed in right, boyesen reeds, 440 mains in carbs any one think this is a good combo? ??? ???
 

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journeyman sled/motorhead
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should fly.what mains were in it stock?
 

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journeyman sled/motorhead
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do they tell you to lean down that much with the head?I only find myself going down 2 jets on ave. with a new sled,because I do not ride in temps lower than 0f much.below that I run stock jetting to be safe.I however do not run their head nor do I think I will,because I don't want to worry about the motor if I get poor gas sometime.
 

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Discussion Starter #5
RKT doesn't say to jet down to that level, they just say to look at the plugs and expect to see it to be rich. kelsey can build a head for any octane and deck height possible. i had my head built for 90 octane, which i can get most every place i go here. everyone i have talked to, and it is alot, said that with kelsey's head desighn you really have to jet down quite a bit due to better combustion, depending on where you run and temps. 440's seem to be the ticket here for that head. i just got the can though, and will be watching the digitron very closely for temps and jetting changes. i also had to add two grams of pin weight with the head, the head works awesome, more power for sure. i was over revving bad last year after getting it, thus the pin weight. with the can this year i hope i don't cook something. :angry:
 

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clutchman that sounds about right,i was also over reving last year,so i bought some heavy adj pins with mags arms to correct that,i was running 440's at -30celcius last year,ive been told by many to start at 450's and move the washer for the needle above the clip,im gonna try that this year,ive heard of many running 410's and 420's on their 800,overall im very pleased with the head,i just dont like the price of premium in my area..lol :D
 

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clutchman,

Are you at 13.5:1 with your RKT domes? Your jetting specs are similar to my riding partner's on his 700 at sea level w/o Boyeson's. I think he stopped at 450's, but the Boyeson's richen things up. I would suggest fattening up your jetting for the first run with the can. I don't know if the MBRP has much restriction, but I had a problem with mine after adding the can even though egts still looked good. Plug checks for the first ride will give you some safety.

SummitAK
 
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