I can't speak for everyone, but I'm not totally thrilled with my DAJs. I bought them and installed them about 10 months ago with the goal of not having to rejet my carbs at the same time that I did the Nyroc muffler mod and added a Napa hose air snorkel and Twin Air filter. Unfortunately, these mods were not enuf to lean out my carbs for the DAJs and I had to rejet the main jets...after trial and error, I found that I had to drop down 3 sizes from stock size on the main jets to get my DAJs to work properly.

PROS:
1) I found that my throttle response improved, but only slightly (actually, I'm not sure if the DAJs, the other mods I installed at the same time or a combo of all is responsible for this slight improvement in throttle response).

2) With DAJs installed, there's usually no need to adjust or shim the carb needles for most common airbox or muffler mods...you only need to rejet the main jets.

3) Easy and quick to make minor adjustments to carbs with the DAJ (especially useful if you often ride at different elevations, like going up to the mountains for vacation).

CONS:
1) Gas mileage is not improved with DAJs installed (this is not really a con, but I was a little disappointed at this b/c I've read or heard others report a little better gas mileage as a benefit of DAJs); and

2) My jetting seems to be more sensitive to temperate changes or dirty air filters from excessive dust as compared to not having DAJs. When I first installed the DAJs, I could ride my quad early in the morning (temps around 50) and it would run flawlessly... but later that same day, it would run poorly at high speeds (too rich). I've had similar problems even after getting my main jets dialed in...now it seems to run flawlessly in the summertime, but has recently ran poorly at high speeds again (as if too rich) in the cool mornings in December (later the same day when the temps rose, it ran perfectly (so I now think I have it jetted correctly for summer, fall and spring temps...but I may need to drop down 1 more size on main jets for winter riding). Also, I have noticed even in the warmer temps that my quad runs great at the beginning of a ride, but gets too rich by the end of a long dusty ride (apparently, my carbs start to run rich as the main air filter gets dusty)...this is noticeable b/c I start having high speed problems again.

3) Not always easy to keep the DAJ air snorkel filters clean and dry during dusty or muddy conditions. I located my DAJ air snorkel filters up near the handlebars area, but I'm always concerned about keeping these filters clean after every ride (more concerned than my regular air filter which has air filter oil to help catch dirt/dust) and also always worried about getting these filters wet during a muddy ride.

4) Kind of a pain to install and once you do, you are kinda committed! By that, I mean to say I drilled no less than 8 holes in my airbox to install DAJs...and there's no going back to stock without buying a new airbox (or trying to repair all the swiss cheese holes in the airbox).

CONCLUSION:
In a nutshell, I would probably recommend DAJs for folks who often ride at different elevations b/c its easy to make jetting adjustments with the DAJs. For everyone else, I don't really think they are worth the money and effort to install them. If I had to do it over, I would just rejet the carbs and reshim my needles instead of installing the DAJs (I don't usually ride at different elevations, so I don't see any real benefit for having them).

Happy trails...[img]i/expressions/face-icon-small-smile.gif[/img]

 

Thanks for that report Mikeyboyesq, nice to see a complete condition and effect report on DAJ's.
I am also at the same jets sizes as you are. I have a love/hate for the DAJ's. I bought my machine used not knowing it had them till later. Sometimes I want to just throw the stock jets back in just to see and have peice of mind. I mainly worry about being lean 3 jet sizes and the DAJ's failing and kaboom.
I have also noticed varying performance with air filter conditions and temperatures. Even at 130 and 135 jets I believe I am running a little rich with the DAJ's set center, however at current temps here in MN around 0-20 degrees lately. I rode for 40 miles with a friend a few weeks ago, he has the same machine but totally stock except for twin air. After 40 miles of riding, I used .7gals more gas than he did. Of course I was in the lead and perhaps was on the gas more than him, but I would say my machine is definately guzzling more gas than his. Also it was -20 in the morning, his machine would not start, mine did, so I'm definately still running richer than stock. I mounted my DAJ filters up near the snorkel intake, perhaps up under the gauge pod would be better, is that where yours are?

 

Yamihoo,
No, I thought about installing the DAJ air snorkel filters up under the speedo pod (inside the handlebars plastic) for more protection from the elements like dust, mud, etc....but then I decided against that b/c I wanted the DAJ air snorkel filters to be very accessible for frequent cleaning.

It sounds like I have my DAJ air snorkels routed to the same place as yours...actually, mine end up on the CVT intake snorkel side and I access them thru the little oval plastic piece located in front of and below the handlebars plastic (aka the access panel to the radiator cap).

I didn't want to locate these DAJ air snorkels too close to the airbox intake snorkel b/c of the potential for air turbulence near that area. I'm not sure how much (if any) air turbulence I'm getting from the locating my DAJ air snorkels near the CVT intake...hopefully not too much.

PS - Thanx for replying above...good to know that others are having some similar experiences with their DAJs.

Happy trails...[img]i/expressions/face-icon-small-smile.gif[/img]

 

yamiho.......don't worry about being lean with DAJs. I don't think it's possible. i was down to 132.135 and still foulding plugs......didn't want to go smaller so i'm back to stock jetting.......i'm almost totally tuned in now......

good luck with the DAJs guys. i don't have teh patients for them.......

Mikey...........i'll make it a point to get the in the mail next payday.......if i don't just send me a virus or somehting....

cart

 

I went the other route and chose to get my jetting spot on using keihn mains and needle shims. After getting things dialed in just right I used TPI valves in my airbox to compensate for changes in temperature/altitude. If it gets warmer I open up the sliders a bit or shut them down as it gets colder, I am really surprised at how much 10 -15 degrees temperature change makes.

It works because I am able to take a stock 700 by at least 6 bike lengths and am dead even with a 700 that has way more mods than I do. We are both running 27" tires of the same profile but his are ITP 589's and mine are mudbugs. The mudbugs are about 7 or 8 pounds lighter than the ITP's are.

 

I always knew there was a reason I didn't want to buy these! Thanks for the report.

 

I am in the same boat as you, by that I mean I did the same mods as you. At first I left the stock jets in and ran some tests. In Low gear it felt like I had a rev limiter installed, the bike was falling all over itself at about 43mph. I lost 15mph off of the top in High. No matter how I set the DAJ it would not correct. I rejetted down (130r/135f) at 2800' and it still would not run right. I ended up taking the Napa hose off, running the DAJ full rich and it seemed to run okay, not impressive, but okay. The only thing that scares me is that I notice my cooling fan running more often than I remeber(which tellls me it is too lean). It definately is using more fuel than it used to and I am still not back near where my top end used to be. All in all I should have left it alone, It ran alot better stock!!!