Well i am starting to lean to the lid on with the snorkle gutted is the way to go!Frist they are very hard to jett SPOT ON with the cover off.The mid is very hard to clean up.That is why Dynojet came out with smaller needles.And they say to keep the cover on.I feel having the jetting spot on is going to make more power all the way for idle to redline!And after all that is were your 0-60 times come in to play or beating that twostroke!And i can play in the creek more!What do you guys think? Skydog[img]i/expressions/face-icon-small-wink.gif[/img]

 

I just got done cleaning the air filter and thats the only thing I am going to touch under my seat. I switch back and forth between a Uni filter and the stock one. I can't tell any difference between the two. Mine runs good from the bottom end to way up in the rev range. Thank you Yamaha carb person for a job well done tuning my carbs. The leave it alone air box lid Chet.

 

First of all, with the Raptor you can't really run with the lid off. The lid helps hold in the air filter, which is probably why dynojet doesn't suggest it. What you can do is chop off the back of the air box lid to get more air in. You can get away with this in most situations, but I tend to rid in more than my share of mud, and do an occasional creek crossing, so I don't feel it's worth the risk of getting water in my engine.

Now, If I lived out in the desert and did nothing but dune riding, this would be a different story...

As for jetting, it's difficult to get things right on to start with. I don't see how modifing the airbox would make it any worse.

 

It is a lot harder to jett with cover off because the carb was desinged to pull a set amount of fuel with a set amount of air. You can change alot of parts in a carb to help get it closer.But not SPOT ON That is why they (Dynojet) had to make smaller needles the stock needles do not let enuff fuel in at mid range.And raising the stock needles to much and you are way to fat down low. I could go on for hours on this but you should see my point.[img]i/expressions/face-icon-small-wink.gif[/img]Skydog

 

run the lid on with vents in the top of the lid. this will let more air in and also gives the protection of having the lid on.

 

I FOUND REMOVEING THE LID DID GIVE ME QUICKER THROTTLE RESPONSE AS OPPOSED TO 2 2.5 INCH HOLES DRILLED IN THE LID.IF YOURE GOING TO RUN WITH THE LID ID TRIM THE SNORKEL FLOW TUBE ON THE INSIDE OF THE AIR BOX LID.THIS PART SITS RIGHT ON THE TOP OF YOURE FILTER RESTICTING AIR.....IF I START RUNNING A LITTLE LEAN THIS WINTER ILL PUT THE LID BACK ON AND IF I NEED IT A LITTLE RICHER THAN THAT ILL TAPE OVER 1 OR MABY BOTH OF THE 2.5 HOLES DRILLED IN THE TOP.
THE ONLY DRAW BACK IS MY FILTER GETS REALY DIRTY.I HAVE TO RUN THE PRE FILTER OR I WOULD HAVE TO CLEAN THE MAIN FILTER EVERY WEEKEND.IVE ATEMPTED SEVERAL WATER CROSSINGS(GOT STUCK IN MUD)BUT THE FILTER STAYED DRY..IVE RIDDEN IN HARD RAIN WITH NO PROBLUMS.
WHEN RERMOVEING THE LID YOU WILL NEED TO USE A PRO FLOW FILTER.CALL PRO FLOW DIRECTLY.THERE ARE 2 DESIGNS OF FILTER SET UPS FOR THE RAPTOR ..THE ORIGINAL DESIGN USED A SINGLE LARGE HOLE INTAKE FOR THE FILTER ATTACHMENT...THE NEW ONES HAVE DUAL HOOKUPS FOR THE FILTER..THE ORIGINAL DESIGN WILL FLOW MORE AIR DUE TO THE FACT THERE IS MORE FLOW AREA IN THE FILTER ,IT TAKES A DEEPER BREATH..THE DESIGN WAS CHANGED BECAUSE SOME PEOPLE WERE HAVING TROUBLE GETTING THERE FILTER ON....(HINT)CLEAN ALL OIL FROM FILTER ATTACHING BASE.IVE HAD NO PROBLUMS WITH THEM AND AIR MAKES POWER.

 

BUY THE PRO-DESIGN KN FILTER CUT THE FLAPS OUT OF THE SNORKLE BUY A 150 AND 155 YAMAHA MAIN JET AND A 25 PILOT AND YOU ALL SET.

01 BLU 660R
GYT-R FRONT BUMPER
GYT-R SIDE FRAME COVERS
GYT-R SHOCK COVERS
GYT-R HOUR/TACH
PRM ENGINE SKID/BAJA GRAB BAR
PRO-DESIGN KN
DURA BLUE AXLE
12 TOOTH
WILDSKINZ HEADLIGHT COVERS
JET HOT STOCK HEAD PIPE
20X10X10-10 PADDLE SKAT TRAK EDGE ITP .190 10X10

 

Skydog,

Do you have the Dynojet kit or not? I have the Dynojet kit in mine and it runs great across the board with the lid removed. I only run the front 2" of the lid so the filter is locked into place plus the baffleless snorkle to help keep out water rushing in from the front.

I run the White Brothers Powerfilter. It is a foam filter that looks much like the factory one except is flows more. In fact, it flows more air than the carbs can so it isn't a bottleneck. It cost about $23. You can get 2 of them for the price of a K&N or 4 of them for the price of the Pro-Design kit.

I own 4 filters. I switch every time I ride and often twice in the same day (depends on whether I am the leader that day or not). I keep the spares stored individually in plastic bags. Because we also have two 400exs and a Kodiak, I am generally cleaning about 6-8 filters at a time.

The inside of the airbox does get dirtier this way. I've never had a problem with water though. You can put a drain tube on with a one way valve if you are concerned about filling the box up with water while riding in the rain. Obviously this isn't going to help much if you submerge it. I don't get into that deep of water on the Raptor so I don't worry about it. I wheelie over mud holes if I can; otherwise, I hit them head on at speed. The splash from doing this doesn't seem to get in the airbox ( most of it seems to hit me instead).

I put the back portion of the lid on when I powerwash; otherwise, water makes it into the box.

 

I did get the Dynojet kit,i should have told you guys i am running the Proflow kit with Knn and a Ct head pipe and muffler.Just dont know if i should just go with the lid or not the Jett kit tells you to go with the lid and cut out the snorkle. Thankyou Skydog P.S.I am starting to pull my hair out!! Ha Ha

 

Below is my reply to IronBear's question about jet sizing. Hope part of it helps this discussion.

As you know, the jet size is greatly affected by not only the exhaust pipe, but by the air cleaner type and airbox mods. I prefer the K&N airfiler that installs just like the oem model. Costs about $70.00, and installs in 10 seconds. For airbox mods, I followed NotuRaptor's advice and:

1.removed the snorkel from the airbox and put a $2 pvc breather on the crankcase breather hose.
2. cut off the back 2/3rds of the airbox lid and threw it away. The front 2" of the box holds the airfiler in place.

I already had a White bros e-series muffler.

I then called dynojet.com tech line and asked what jets would be preferred for the above configuration. They said to buy the K&N stage 2 jet kit (that dynojet manufactures) and use the 148 and 150 jets in the left and right carbs, respectively. They thought this would work best in the 0-3000 ft elevation, and run a bit rich above that (but with little consequence).

I tested this setup last saturday, and the results were suprising. The earlier muffler change had shown hardly any benefit, but now with new jets, K&N, and airbox mods, this baby flys! More low end torque, and more hp in the hi revs too.

I'm not sure if dynojet would recommend different jets for your Big gun or not. might be worth the call. Enjoy.