Today, I did some more timed runs at 100' and 300' to find out which Dial-a-Jet setting (settings go from 1 to 5 with 1 being the leanest and 5 being the richest) is fastest. Everything ran smoothly and strong when I ran tests with the DAJ settings at 1 thru 4. Then, I set it on 5 (the richest adjustment) and in this setting, the motor surged badly and it never made it over 55mph. I quickly decided not to do timed tests on this setting b/c it ran so poorly.

After I returned the setting to the setting with the fastest timed runs (which happened to be setting 3), the motor still surged at 30 mph and up...but not as badly as it did when setting was on 5. I ran it a few minutes with no improvement, so I tried returning the DAJ setting to 2 (a little leaner than 3) and it ran the same.

ATTEMPTED SOLUTIONS THAT FAILED
The inside of the airbox appears very moist with gasoline...(note: the DAJ bodies are designed to purge a little gasoline everytime you let off of WOT to clean it out). I opened the air box so this gasoline would evaporate and I drained the carb bowls...started it back up and it still surges! I then pulled the plugs (they were both black) and cleaned them up. This also failed to fix the problem.

I called Lonn at Thunder Products (he is the owner/seller of DAJs) and he was no help...he says its not the DAJs...but does not offer any real answers for why it ran great until I set DAJ at number 5 and has run poorly ever since.

HELP!!! Anyone know what else the problem could be??? Keep in mind it runs smoothly from 0 to about 30mph and then it cuts in and out/surges from about 30mph up to top-speed. Also, it runs smoothly from idle to WOT when I rev up the motor in neutral...that leads me to believe the problem is connected to the DAJs. Any advice for me???

PS - I have a cross-country race this Sunday and I need to fix this ASAP!

 

Hey i was having the same problem if you recall..... I finally got so mad at mine after trying countless jet combo's and adjusting the dial a jet that i gave in and took it to a performance shop, they hooked it up to a gas analyzer (dyno) and here's what they found....

My home alt. is 4200 feet.
I had 135f 140r jets installed.
I have twin air filter, napa snorkle, and nyroc's exaust mod.

They told me that i was jetted 3 sizes to big.[img]i/expressions/face-icon-small-shocked.gif[/img] They droped my jetting from a 135 front to a 120 front and from a 140 rear to a 125 rear. (This is with the dial a jet on the middle or stock setting.) I asked about my needles and piolot screws and they said they did not need to be adjusted.

I ran it down the street and hit 60mph rather quickly.[img]i/expressions/face-icon-small-smile.gif[/img] It did cough once at 58 mph and i told the service manager about it, he took it for a ride and it did the same thing to him...... he gave it a little choke and it got worse so he opened up my air box lid vent (tpi vent) and the problem was gone.

I still don't under stand why it coughed a little and the only reason he could come up with was the temp change.... about 70 degrees inside of the shop where it was dynoed and about 52-54 degrees outside where i test drove it.

So maybe you are to rich.[img]i/expressions/face-icon-small-confused.gif[/img] I thought my air intake mods would lean me out enough..... guess i was wrong.[img]i/expressions/face-icon-small-disgusted.gif[/img] Either way it runs pretty darn good now and im gonna leave well enough alone.

Good luck.

 

2003650,
Thanx for the response. I would also guess that mine is running too rich judging by the amount of gasoline in my airbox (which appears to be coming from the DAJs as they purge after letting off of WOT)...however, the thing that puzzles me now is that my quad was running smooth and strong with the DAJs for the last timed tests I did about a week ago and also ran just as smooth and strong this morning until I adjusted it to setting 5. I know for a fact that my quad was running very good with the DAJs until I set it on setting 5 (richest setting) and I can't seem to understand why it won't run the same as it did now that I have reset it to setting 3.

Any other guesses as to why it ran great with DAJs before and now it runs terrible after adjusting it to setting 5 and resetting it???

 

Mikey

Sounds like your rich, a couple questions,

when you use the numbers 1-5, is #1 the smallest hole or the largest.

When you make changes to the dj's, do you loosen the screw on top first.

Did you try cracking your air box, and make a run.


It is your dj's, they don't work when the motor isn't under load, therefore they don't work in netrual, that is why your bike is runing good in netrual.

How many jet sizes did you go down, for the dj's

 

Ya, I'd think you were rich... I think I told 2003650, that I thought he was rich, when he posted a week or so ago, also... if the quad is not lean, the Dial-a-jets won't function... as to why the different results from your timed runs to now ??? is there a temp difference ??? here in Minnesota, that can be a real issue, however I doubt that you were running lean enough if there was a 20* temp difference between then & now ???... I'd drop a size front & rear, & see what happens ???

 

Shotgun,
The #1 setting (leanest) is the largest hole.

Yes, I loosened the screw first.

Yes, I tried running it without any top on the airbox (and without any air filter)...it runs almost exactly the same...and still have surging problems.

I did not change jet sizes when I installed the DAJs b/c I leaned out the carbs at the same time by adding Napa hose, twin air filter and doing the Nyroc Mod. BTW, I'm at 100 feet above sea level here.

Newbeatle,
Yeah...I'm starting to think that the reason my quad ran well a week ago (in the early morning) and again early this morning was b/c the temps were about 50 degrees and I first noticed the surging problem around 10am this morning when the temp had already risen to the low to mid 60s. Maybe this 10 to 15 degree temp change was enuf to make my carbs run too rich for the DAJ's??? What do you guys think?

As stated above, I'm a little desperate to fix this ASAP b/c of a race on Sunday. My local Kaw. shop does not carry smaller size jets in stock...so I'm considering an order from Ron Ayers and have it delivered overnite on Friday so that I'll have time to rejet (go down 1 size on front and rear). I'll post back here after I finish rejetting...I must say I'm disappointed that I have to rejet b/c the main selling point for me on the DAJs was that I could possibly avoid rejetting by simply adding some airbox/muffler mods at the same time.

 

Sorry for asking stupid questions, but you would be suprised of the people that email me asking about the DJ's and think the the largest hole is the richest setting, so they adjust backward.


With the race on Saturday, the first thing I would do is unhook the DJ's from the bottom of you carbs and try it without them (leave every thing in place). You must have been rich before you made the changes to the airbox.

The spark plugs are the answer, change or clean your plugs make a run, look and see if your rich or lean. get the bike in a lean condition and hook the DJ's back up and try again.

Good luck

 

UPDATE
I ran my quad this morning (50 degree weather) and it ran perfect again. Then, I ran it again on my lunch break (about 70 degrees) and found that it surged a little...to me, that indicates the increased temp was the reason it started to run poorly the other day and it was not the fault of the DAJs. I'll keep you posted on my progress after I install 1 size smaller main jets in the carbs.

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

 

Mikey, Try a new set of plugs. It's possible one or both are still fouled, depending on how good you cleaned them. If it still runs bad, keep them as spares.

 

Mikey, if it's running rich in warm weather on ALL DAJ settings, I would consider going down at least 2 or 3 sizes on the main jets.