Don't take out the Dynojet kit, just tune it. Use the conversion chart below - find your brother's Mikuni jet on the chart, and use the corresponding Dynojet main to get the same fuel flow he has - that is if your air/intake set-up is the same. Try it and see what happens - maybe you'll be back to beeting him, and still have the better throttle response off the line that the Dynojet needles offer.

Dynojet/Mikuni conversions

 

<< Ok heres the deal. My buddies and i got together this weekend to do some trails and messin around on the quads. Well my one buddy picked up a new Z400 and just piped and filtered it and wanted to see how fast his was compared to my Raptor. Well I killed his Z400 easily. Then another buddy lined up with his ported shee. I beat him too but it was pretty close. Then my brother lined up with me on his Raptor with the exact same mods as mine except his is using mikuni jets and i am running a Dynojet kit. Well He spanked me pretty hard! By like 3 quad lengths. The bad part is that i am a better rider than he. Before i put in my Dyno Jet Kit i was faster than him cause i have a better riding ability. Now after i put this Dyno Jet kit in he spanked ME!? Whats the deal? I tuned the kit and and have the jetting spot on. I jetted his with the mikuni jets and it is spot on. Why is his faster? We weigh the same. and everything. Guess i am taking out my Dyno Jet kit and selling it. That was realy depressing. But i guess it made my brothers day. >>




man that guy with the ported shee must not know how to ride, or maybe he needs the dyno jets lol.

 

Dynojet main jets are $2.00 each, same as Mikuni jets. The price of the kit has nothing to do with the main jet assortment - you're paying for the technology that was involved with designing a superior needle. What's so hard to understand about that? Anybody who has a Dynojet kit installed, and doesn't recognize the better throttle response and holeshot from their needle, made a mistake or two and its not tuned right. No offense implied here - I'm just stating the truth. I've only used Dynojet kits in 3 different bike brands, but other people I ride with have covered the other brands, and I can say that I've ridden and felt the superiority of Dynojet needles in most of the bikes out there.

You also have to keep in mind that these needles were designed using stock motors for the testing, so if you go wild on internal mods then it may not be the best choice anymore.

 

Amen!

 

Dyno jet works fine for mild air box mods, we are talking major mods here(no lid) &amp; the kit isn't worth the money then. Actually you can file your stock needles to mimic the Dyno jet needles taper for no cost &amp; then buy a few mains that you need, not a lot of extra ones that you don't &amp; save about $40. Makes sense to me, why spend extra, that should be easy enough for you guys to understand, unless you are Dyno jet reps?

 

B.S. Yeah I am a Dynojet rep in Mississippi!

 

I had a dyno jet kit in for a year, pulled it out. Runs alot better all around. Messed with the dyno jets till i was blue in the face. Waste of money. Another raptor rider pulled his out after seeing mine run much better. He is happy also. 2 jet kits for sale cheap. I do not see many aftermarket companies pushing dyno jet kits with there mods. Why? Probably the tuners think it is a waste of money. I did keep the 2 springs in. They are 40 dollars apiece. lol Live and learn. You can get there alot cheaper than dyno-jet.

 

Well i talked to dyno jet til i was blue in the face. They had me try like 50 different things. Still no go. After all this the guy told me strait out that this isnt the first encounter with this problem. He said that the Dyno Jet kit even tuned well will be slightly slower than a mikuni tuned bike. He said that most people like the dynojet kit for the low to mid HP increase over stock. (Trail riders only) He thought my tuning may be out since my brother beat me so badly. He recommended CT's needles with the mikuni jets. He said a better top end performer. Well I think i will stay with my stock needles and get rid of the dyno jet kit. This was realy a waist of my time. I tuned everything. Valves you name it. I had a dyno jet kit in a shee before and it was great! Maybe they didnt spend enough time on the Raptor. I dunno. I guess if you want massive throttle response and improved low end the dynojet kit wouldnt be a bad deal. But to me the Raptor is all ready a tractor and doesnt need any more low end. Thanks for the help guys!

 

Just have to say &quot;Cannondale&quot; throw away the carbs and go fuel injection. No more problems!!!

 

Well I spent an entire day tuning my bike with the stock needles. I changed it a bit from what i had done to my brothers. Now even better power than his. No more flat spots just keeps on pulling all the way up the RPMs. Now this is what i am talking about!!!