Heres the deal, my buddy just bought a Raptor and took it to the little sand hills near Walden Colorado, which sit at an altitude of 6000-9000 ft. and it ran like crud. IT would not climb any of the tame hills in any gear but first. I know Raptors run better than this!(I raced a stock Raptor at Glamis and almost got more than I bargained for!!) It is completely stock and he is going to take my advice and go with a 12 tooth sprocket in front to help, but is this all that is needed? It is completely stock and was running the stock tires in cold, hard packed sand. He is getting conflicting information from a few dealers around here. One recommended a jet change from the stock 140/145's down to 125/130's, which resulted in popping, indicating a lean condition. So my question is, what kind of jetting do you guys run at this altitude, again 6000 to 9000 ft.? What are some of the lowbuck (no buck really) performance gains you guys are doing? I know that when the Raptor first came out, some people were talking about the airbox inlet being blocked by some plastic inside? IF this is taken care of, will it help? What else have you Raptor lovers done? Any comments are greatly appreciated!

RoostKing...

 

my raptor was rich at 3200ft with stock jetting.id pull the spark arrestor out and mod the air box.take the air box lid snorkel off and put a filter on the vent tube that comes from the crankcase.then cut all the duct out of the lid that feeds to the opening the snorkel attached to,also drill some 7/8 or 1" holes in the lid.and id start with the stock jetting.air box mods really affect the jetting.i have a full big gun system with the air box modds listed and run a 155/160 main jet with a 25 pilot jet and the needel in the 2nd to top position.also i had to use a 105 choke jet so it would start when it was cold out.my altitude is 3200-3500ft.start by getting the main jet correct.i also noticed when i tried a 150/155 main it wouldnt pop on long wide open runs but would act like it was running out of gas. after putting the bigger mains in it doesnt do it.after that it ran good but didnt seem to have the stong mid range punch it had before,it just labored through to the top end so i leaned out the needel and it runs great.one thing do all your jetting with the air box set up like you want it because any change makes a big differance

 

A friend from northern Colorado told me he went down 2 steps on the mains. I plan on going up there this summer and that is where I will start with the jetting.

 

Thanks guys,

RaptorRider, could you ask your buddy exactly what his jetting numbers are? Since jets come in varios incrememnts, I am not sure what 2 steps would be. MAybe 130/135's? Again thanks for your help...

ROostKing...

 

Roostking, How was Walden. Any snow left? I bet there's some now!!!

By the way, If I were your buddy I would do any type of intake mods (K&N, lid, intake blockage thing) first then jet. 4 Strokes aren't so sensitive to the jetting like the 2 strokes so I am a little surprised he is having trouble if it ran OK at Pawnee. My warrior works great anywhere from 5000 to 11000 feet.

 

Bought mine from Vickery Motorsports in Denver. They set it up for this altitude.

Stock: Right-145, Left-140, clips in 3rd notch from top on both, Air Screws 1 turn out for both.

High Altitude: Right-135, Left-130, clips and air screws the same as stock.

Where did your friend buy his Raptor? If it was in Colorado it should have been set up properly at the dealer.

 

roadkilljoe, where do you ride in denver area.i ride mostly in Granjunction or Gypsum (theres a track out there)pretty nice to.email me .maybe we could ride somewere together.glen0022@aol.com

 

We're at 4500-5000ft and we're running 145-150 and it's right on. My mods are listed below. Moved the clip to the number four slot. You should leave the jetting right where it is for your elevation.

 

MY buddy bought his at High Altitude Yamaha in Cheyenne,Wyoming. This dealer, although pretty cool, just dont really care much about quads, they are snow mobile freaks. At any rate, my buddy is going to go with the 130/135's and see what happens, which seems to be te general consensus on the board. As far as Walden is concerned, it was pretty fun, other than getting stuck once in a while and having to pull the Banshee through drifts. Keep the comments coming, they are greatly appreciated...

RoostKing...

 

Here is the set u I found best for my bone stock Raptor for High Altitude Riding:

Right-135, Left-130, clips and air screws the same as stock.
Hope that helps...