Ah, I need to update my profile. I have the HMF and you just go from a 150 to a 155, not mods needed on the airbox!! And it sounds really sweet. I got many compliments on the sound, fit, and finish of the pipe!

 

my polaris dealer told me that a 13 36 gearing would be the best for dunes... any opinions?

 

I had the dealership install the pure polaris pipe before I took it home. The dynojet kit, front sprocket, and filter with outerwear I purchased Pocatello Power Sports in Pocatello, Idaho. It was all very easy to install. Completely remove the airbox and snorkel first. The hardest part is installing the dynojet kit, and it's really not that bad. It comes with everything you need to do it., along with complete instructions. The needle has to be changed, it comes with an assortment of main jets so you can get the fuel dialed in. It also comes with a drill bit. You use this to drill the plastic cap off the air screw. I'm not sure why Polaris did this to begin with, but I'm guessing it was so nobody could mess with the mixture and screw it up. After this cap is drilled off, this allows you to adjust your mixture, although it only seems to affect anything below about 4000 RPM's. It tells you right where to set the needle and what jet to start with for your elevation. It still takes a little tweaking after you get it runnig. Your idle has to be adjusted every time you change jets, but it can be done with no tools.

I also removed all the restrictor plates out of the back of my pipe. This helped also to get rid of any kind of restriction. I then just bought a tip so the sound levels were bearable. This combination does wonders. It helps so much. I started eith airbox mods and the K & N that replaces the stock filter. My new setup works much better! I tell everyone I talk to that all they need is to breathe breathe breathe! Even with the airbox mods, it was still choking for air. The only other thing I did is to put an in line fuel filter in the end of the breather hose that used to go on the backside of the airbox. It mostly only pushes air out, but just to be safe, I put an in line fuel filter on it. That really is all there is to it!

You can go through the gears like a dirt bike. It tachs so fast! The mid and top end are awesome now. The gearing works great for dunes or windy trails. You basically drop the ratio enough that you almost lose all of 5th gear. My buddy and I clocked it and top speed is almost exactly 70. You should try it! I promise, you would nver go back! I raced a freind on his stock machine, and of the line it isn't even funny. When I ran out of gears, he was a good 4-5 lengths behind! Of course he caught me on the very top end because of his longer legs, but how often do you go over seventy anyways?

Let me know if you want more info.

 

Reffrey- What gears are you running?

 

I am running 13/37. I just dropped a tooth in the front and left the rear at stock.

 

Yeah! I think he was trying to say that more torque is generated on the rear sprocket with a smaller front sproket. An overblown but simple analogy would be if you had a 2x4 and and someone was holding the end of it and you tried to force them to spin around you in a circle holding the other end while you rotated standing in place. IT would be a lot more difficult to make them turn around you if the 2x4 was 16 feet long rather than 2 feet. See my point? It has to do with inertia and torque.