Am I in the jetting ballpark!?!?

[Pincushion]

Got a stock motored 03 w/ FMF Fatty's, FMF S/A silencers and K&N pods. TORS is also removed.

I'll be riding the Oregon Dunes this weekend (sea level, 70F and low humidity). I was thinking about running 300 MJ's, 25 PJ's and 1.5 turns on the air screw (and adjust as necessary). Does this sound like a winner based on my setup?

 

Also, I just got back from the dealer to get some 27.5 pj's. I removed what I assume is the PJ from the carb and bring it with me. He tells me it is not the PJ and that Mikuni's use a fat-head style PJ. I told him that the PJ I brought with me was removed from the recessed shaft right next to the main, just like where it has been on every other 2 stroke carb I've touched.

 

This picture shows 3 different PJ's that I received with the bike. The one on the far left is a 25 w/ no Mikuni logo. The middle on is a 40 w/ the Mikuni logo (this is also the jet that was in the carb when I got it) and the right one is a 160 (Yes, a 160) and the cavity is 4x the size of the 40.

 

 

Sorry for the long post, but I'm fucking confused and dont want carburation issues. Is my dealer the stupidest man alive? Are these pilot jets? Why the hell do they have different thread patterns (look at the left one compared to the rest). Lastly, I'm not comfortable using that 25 since it doesn't have the Mikuni logo on it. Is it some cheap knock-off or is that the stocker?

 

Thanks!

Edited September 11, 2008 by Pincushion

[pr0blumz]

The type like the one in the middle is what you want. Use a 27.5 instead of a 40. :thumbsup:

Edited September 11, 2008 by pr0blumz

[Pincushion]

Thanks!

 

I'm guessing that fat 40 pj is the reason it takes 10 minutes to start the motor too.

[ASRBanshee]

Yea no reason you should be running 40 pilots. It goes #15-35 in increments of 2.5 and #35-65 of increments of 5. You want a 27.5 pilot but make sure when you specifically ask for them you say banshee pilot jets. Because the mikuni pilot jet that fits most carbs DONT fit banshee carbs. As far as the mains you want to be like 320-330 mains.

[Pincushion]

The plot thickens.....

 

I got some 27.5's today. They're original Mikuni's and are the correct ones.

I thoroughly cleaned the carb, reinstaledl the 320 mains I'd been running and swap the 40's for the 27.5's. I button everything up and the SOB will not start. I kicked it 100 times and triple checked everything.

 

I had just installed some idle screws the night before, so I try every different depth combo possible. One turn out to 20 turns out, nothing! By now I'm shitting my pants thinking something went wrong with the idle screw install. For giggles I reinstall the 40 pj's, button it back up and the fugger fires right up and purrs like a kitten and revs up fine. WTF!?!?!

 

I set the idle screws and everything is great. My motor will not start with 40's and those carbs are cleaner than new! I dissasembled everything and cleansed them like nothing has been cleansed before. The dude I got the quad from said the motor is bone stock, only the bolt ons I mentioned above. It was 80f, 300ASL and low humidity today.

 

One change I did make was change the stock needles from #3 to #4, but that wont affect the pilot circuit at startup. My compression was 125L/125R and I checked it about 2 hours (run time) ago. Odd, eh?

Edited September 12, 2008 by Pincushion

[dajogejr]

Have you tried changing the air screw setting? Is it almost closed?

Is the choke tube between the carbs....and lastly, do you have the slides in the right carbs (half moon shaped cut a way should be facing the rear of the bike)

 

Any of the above can make for near impossible starting.

[Pincushion]

Have you tried changing the air screw setting? Is it almost closed?

Is the choke tube between the carbs....and lastly, do you have the slides in the right carbs (half moon shaped cut a way should be facing the rear of the bike)

 

Any of the above can make for near impossible starting.

 

Air screws are 1.5 turns out. I haven't messed with them, but I think they need to come out further.

Tube is in place. And the slides are correct as they will not seat properly if installed incorrectly.

 

I'll try adjusting the air screw out as I flooded it while trying to start last Saturday at the dunes. After push starting it, she fired up first kick all day. It seems a 27.5 doesn't deliver enough fuel to start and the 40 delivers too much. Going to shoot for something in the middle and test.

 

 

thx for the reply!

[dajogejr]

The carbs slides will go in and seat in either carb, but only one is correct.

The cutaway is for idle and starting...so that's why I said check them...

[Pincushion]

I see.....

 

the cutaways are facing the rear and the slides appear to be in the proper carbs. The cable 'memory' has each one going to the carb the cable naturally wants to go to. If that makes sense.

 

Are the slides the same and only the cable length different? Or is each slide unique to the L and R carbs?

 

If performance is any indication then they're good. The bike fuggin screams and idles like a kitten once I got it past the initial pain-in-my-ass starting procedure.