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Discussion Starter · #1 ·
Hey guys. Wondering if I can get a few opinions. Ive finally got at least my sled back together and running. I got an aftermarket pipe over the summer as my stock one was destroyed. Its a big single Aaen fatty with asingle stinger built in completely eliminating the can.

I want to jet it properly and Im wondering if you guys (BC Dan!) know what I should do. They jet sizes for kiehn flatslide carbs go up by 5s. Stock is a 185. I bought 190s 195s and 200s. I test rode it a little today and plugs were light brown a little on the lean side on one half of the electrode. And thats at 41 degrees and raining :dunno:

What do you think I should start with? is a 185 to 190 a big change at all? Im fine with tearing it apart more than once to get it right, but just wondered what you guys thought the first set I put in should be. This is my first time doin jets, on a sled at least. Let me know what ya think! thanks.

Heres a video from when I first got it on.
 

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The Keihin jets going up 5 would be a whole step, similar to going up 10 in a Mikuni. Aaen should be able to give you jetting requirements for their pipe, they're very knowledgable and helpful! In the absense of the manufacturer's jetting chart, I would start with the 200's, especially if it gets cold out, and work down. Rich is safe!! When it gets cold again, you will be too lean and take a chance of burning holes in your pistons. It sounds like it's jetted perfect for 41 degrees. but who wants to sled in the rain!
 

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Discussion Starter · #3 ·
It sounds like it's jetted perfect for 41 degrees. but who wants to sled in the rain!
:) my point exactly. I did ride it around the house a bit yesterday and down a mile to a restaraunt, but I was checkin plugs every 5 min and knew that the extremely humid warm air was aiding me in not burning it up. if it were -10 degrees it would have been a much different story. I appreciate the advice, as my plan was to start with 190s and work up, but your very right saying rich is safe. When you put the twins on your wedge 700, how many steps up did you have to jet that? do ya remember?
 

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For my sled at 6-9k elevation, I was running 170 on the PTO side, 175 on the MAG side, needle clip in the third slot, a 6.0 slide, and a R1368G needle. Those were PSI specs for that sled at my elevation and temp (-20f to +20f, if I remember.)

Stock was a 158 jet, so it was quite a bit bigger with the twins. I would go at least 3 sizes bigger and make sure you test early and often to make sure it's safe!
 

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Discussion Starter · #5 ·
Well I got the sled fully together and jets in! And BC Dan, im a bit confused about your jet sizes. The dealer told me stock jet for my sled was a 185 and that jets go up in 5s. Well the stock ones I pulled out were stamped 182s... ? so not going up by 5s...but whatever. But what Im confused about was your 700 was running 158s?! thats much smaller than my 182s stock.. Did your sled have Mikunis? and are there jet numbers irrelevant to Keihns?


But anyways, the sled is together! I stole the track off the 94 XCR 440 because my girlfriend doesnt need one that nice anyways right? :dunno::laugh: its a 1 1/4" with 96 1 1/2" (i believe) carbide tipped Stud Boy studs. AWESOME track. and the 1" track I bought at Haydays will go on the 440. I also had to replace the entire chaincase! Found out when my track let go with the speedo readin in the 110 neighborhood during a radar run last year it did more damage than just the track and bend the rear of my tunnel and bumper. It sheared the bolt holding the lower sprocket on in the chaincase... so a bolt head and washer were flying around inside there at tremendous speed. It blew out the whole bottom of the big cast aluminum chaincase! New gears, chain, case, and cover were needed... SOOO.. I had a good chunk of work to do, along with bodywork to make the tunnel straight and the snowflap not wanting to get pushed up on the track and in the tunnel. But it seemed to work good, and heres the video to show the results! Wish I would have been a little closer when I set the chair up to make a video, as its a lot more aggressive sounding in real life, but thats how it goes. Anyway, cant wait to get back on the snow! BRAAAAAAAP! :cheeky4:


 

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Discussion Starter · #7 ·
thanks! I LOVE it! it is a bit on the loud side yes, and I said i would never be that guy to have the super obnoxious sled... but the deal was right and my stock exhaust was shot. Found this pipe in my same apartment complex and did a trade for some engine parts I had and HE kicked in 100 bucks. If you watch my first video you will see how bad my stock can was from the crash, and it was just as loud as it is now, but not in a good way. Now it sounds crisp and good, not just loud and blaahh.. I love it! and the power increase and weight decrease is the best part! She was standing right up out in the field today! BRAAAAAAP BRAAAP!!
 

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Yea I saw the first video and that stock exhaust wasn't in too good of shape...haha. Glad you got her on the snow again! I should have my EXT going by Thursday next week.
 

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The jetting I quoted was for my 97 RMK, jetting for that sled is a lot leaner than the XC. They jetted the RMK with a different slide, needle, and jets because most RMK riders were in the mountains and required much leaner jetting. Carbs are the 39mm Keihin D-slides, just like on your sled. Dennis Kirk has a list of Keihin jets, they definitely have a lot between the 5's.

DG Keihin 13 Series Main Jet - DennisKirk.com=
 

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So with a bigger jet size would one have to expect using more fuel? That seems like a logical conclusion to me but I don't really know...I'm supposed to be running 470's, stock is like 340 I think :0
 

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Discussion Starter · #11 ·
ok I understand now BC Dan, and also I see why the dealer told me it went up by 5s. I see on the drop down list on Dennis Kirk that the 182 jets (stock) were the last jet which werent going by 5s on the way up to 200. So I have every jet they offer from stock up to 200. But I do see that below 182 they have many which arent going by 5s.

jwaldmann, yes theoretically you will use more fuel... but when you think about the size different in the bore thru the center of the jet its far from dramatic like your mileage is going to drop in half or something.
 
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