Working on a friends 03 raptor, we installed an HMF full exhaust and k&n filter.

Per the dynojet instructions we used the dj144 dj146 mains, needles on 4th clip and turned the air screws out to 3 1/4 turns. We also cut the flaps in the lid but nothing else.

The quad is now slower than stock, no real problems and trottle response seems good but there was a decrease in over all power. it doesnt skip or bog really, just less power than stock. On my raptor I have a gytr slipon, no lid, mikuni 160/165 and clip on the 4th and there is a considerable difference when you get off the 03 and get on mine with just the gytr.

I was thinking maybe going to 165/170 on his and mod the airbox some more, do away with the dynojet alltogether then run stock needles on 4th or 5th clip. we are below 3000ft.

Any ideas are appreciated!

 

Try cocking the air box lid by only fasteninng the front clips and leaving the four remaining(two on each side) under the lid to create an angle which alows more air flow...while this isn't a permenant fix it is however an easy way to check if you have enough air delivery. I ran my box like this for months in wet and dry weather without any problems...the lid angle also deflects most water.... good luck

STUPID AIRBOXES
JW237

 

I just came in from screwing with mine...I went with 165/170 mains now, needles on 4th clip down from top, air screws at 2 1/4 turns out.

Thats with my trinity pipe and aluminum airbox with an outerwear cover over top the box. I think it's still a tad lean though, it's kinda crappy out righ now to go and put some time on the new plug. It's not showing too much right now with just a couple trips around the block.


Have you done a plug check to see if it's running rich or lean?

 

We ran it with the lid off alltogether just to see, and it didnt really change anything.. if anything it got slower so I am thinking lean..

anybody know what DJ main would equal a mikuni 165/170??

 

go 146/148 mains. if it is fat in the middle drop the needles to 3rd clip. With lid off you may need 148/150 mains.

 

We put in the 148/150 dynojet mains, and dropped the clip to the 5th pos, it is worlds better but still seems to be lacking. We are still running with the lid on and just the snorkel flaps cut. It sounds a little richer as well.

Does anyone know what mikunis the DJ 148/150 corresponde to?

 

my guess is that you are now fat in the mid range with the needles all the way up in the 5th clip possition. my stock motor ran great with no lid, k&n, 148/150 mains, needle in 3rd clip postion. Try the 4th clip. you'll get it [img]i/expressions/face-icon-small-smile.gif[/img]

 

I have a 02 with HMF and the dynojet-
I had the shop jput the jets in and there Is a HUGE power difference in my bike- never had a problem

 

Well we raced and he is now edging me out.. I wiegh a good deal more than him though. so long as he is beating me he is happy and we will see how it goes at tomorrows ride.