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jetting for HMF slip on + K & N Filter?
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Posted by: nakedfrijoles

What is the best jetting option for this setup? If anyone would be willing to share their setup or have any advice i would appreciate it

Posted by: matt1106

You should put the filter and slip-on on ur quad first and see how it runs, because i put a white bros slip-on on and a K&N filter, and mine runs great. And i never touched the jetting. The guys at my local shop told me that if i didnt re-jet my quad it would run like crap, and I couldnt even notice a differance how it ran at all, it was just a lot faster. But that just may be my conditions, too, but you never kno its worth a try. you mite be able to save yourself some work

Posted by: nakedfrijoles

ok thanks ill give it a shot

Posted by: oleboy87

well i have the hmf slip on with a k&n filter and an open air box im running a 170 jet in mine... runs great!

Posted by: matt1106

if you do try just the filter and the pipe, keep the lid on, if you take it off, it will definatly run lean.

Posted by: oleboy87

i called hmf when i installed the pipe and asked for the jetting specs for my set up and he said put a 170 with an open box and he was right.. its dead on!

Posted by: WFO400

I have an HMF with a uni. I just went one size bigger on the main to a 155 I believe it was (it's been a while). It runs great and I didn't touch any other jets. It didn't run bad at all with the stock specs, but it's definitely better with a bigger main.

Posted by: Pipeless416

im running an hmf s/p with a k&n without a lid. im running a 160k main, 42 pilot, needle is one clip lower than stock, and the air/fuel screw is 2-1/2 turns out.

Posted by: hornetgod13

I'm running a 155K in the summer and 158K main in the winter and the plug check is paper bag tan. I have a HMF Slip on, UNI filter and EHS Racing lid. A 170 sounds rich. Are you running Keihin or DynoJet jets?

Posted by: Wheelie

I agree, 170 sounds rich. A 155-160 is about right with a slip on, filter and no lid. Most pipe manufacturers recommend jetting on the rich side.

Posted by: 400exrapes

well i have a stock filter with lid on and i run a 150 main and 40 pilot, runs perfect in about high 80's and low to mid 90's never tried it in the snow but im pretty sure its perfect, im about 400 feet about sea level. My guess is that you will be anywhere between a 150-155 main and a 40-42 pilot will both work for you. thats depending on your elevation and temperature as ive learned from members of this great site.

Posted by: tanner 222

i got the same pipe and filter and i run 165 main and 42 jet and i noticed a huge difference in power so im guessing its good. i can also run it either with the lid on or without.

Posted by: nakedfrijoles

THANKS guys for the help...i live at about 700 ft above sea level..all i know is that i am running the main that came with my hmf slip on.. i cant remember what it was...but other than that i didnt change anything

Posted by: oleboy87

well im right at sea level and the main that comes with the hmf is a 165. but im running an open air box soo hmf specs calls for a 170 and im running dyno jets...

Posted by: hornetgod13

quote:
Originally posted by oleboy87
hmf specs calls for a 170 and im running dyno jets...

Dynojet, that explains it. You didn't mention that in your other post. I assume stock keihin jets unless otherwise mentioned.

Posted by: oleboy87

sorry for the confusion... i didnt know between the two diff kinds of jets that there was that much difference

Posted by: hornetgod13

quote:
Originally posted by oleboy87
sorry for the confusion... i didnt know between the two diff kinds of jets that there was that much difference

Dynojet and Keihin jet sizes (numbers) are completely different.