Carb. adjustments on Sportsman 700? Attn CHADD!!

[Pepe]

I have a 2002 Sportsman 700 with ~1900mi in it. All I have done is regular oil changes and greaseing. On the last trip I noticed it would hesitate on full throttle hill climbs. So I decided it was time for a tune up to see of that would help. I put in a new air filter, fule filter, cleaned the breather filter, and new NGK-BKR7E spark plugs. The air filter was dirty (as expected) and the plugs were some what sooted up from running too rich. I started it up to warm it up for the oil change and it was ideling noticeably high. I read the owners manual and shop manual about the idle speed adjustment. I started it up in diagonostic mode and turned on the tach, it was idleing at 1800 rpm. (manual says it should idle at 1200 rpm + or - 200) I slowly backed off on the idle adjustment screw several turns with no change, then I screwed it back in untill it idled up to ~2200rpm (too lean) and slowly backed off untill it idled back down but it never went below 1800 rpm.


So now what? I figure the plugs are the main reason for the change but they seam to be the same heat range and I did check the gaps at .35". I could adjust the pilot screw but I wanted to ask for opinions first. Also what is the correct proceedure for adjusting the pilot screw and the idle screw? How many turns do you back off for the base setting?

[Pepe]

Also how do I get the plug out that covers the hole to the pilot adjuster hole?

[Mr. Miyagi]

Hummm..... Just an idea. Maybe that plug is there for a reason. Are you sure you want to start modifing the pilot screw? Just a thought....

[Rogue]

The plug is there because mikuni carbs are such a pain the butt to tune that unless you know what you're doing, you shouldn't mess with it.

However, if you want to remove it, it is simply a brass plug. Take a drill and very carefully drill it out. It's about 1/3 of an inch deep. I'm not sure on the 34mm carb, but on my Predator carb, which is 40mm, the first plug looking at the intake side is the fuel/air screw, the other plug goes to something I have never messed with. I have only used the fuel/air screw.

[Chadd]

The plug is there for emissions crap. The lovely state of california doesn't want us messing with the settings. like rouge said just drill it out then thread a screw into it and pop it out.

can you turn the idle srew all the way out and it still won't idle down? is the throttle cable to tight?

The pilot air screw adjustment should be 1.5 turns out .

[Pepe]

So it sounds like I will have to remove the carb from the bike to be able to drill it. I will check out the throtle cable but I doubt that changed. I just want to clarify this, I should turn the idle screw out to lower the idle rpm?


I feal like I am coming across as a complete newbe when it comes to wrenching on things. Honestly I think I am competant mechanic. I just like to do my home work before I dive into some things, and the service manual is no help whatsoever with the carb.

Is the NGK-BKR7E the right spark plug?

Thanks for the help guys!

[Pepe]

Well I was wrong! The throtle cable was the problem. It looks like one of the kids has messed with the freeplay adjustment on the cable. I know it wasnt like this when I shut it off a few weeks ago.

But it is running a little on the rich side. How should I go about leaning it out a little bit? I am currently at about 100' above sea level and most of my rideing is at around 3000' to 9000'. Do I need to rejet it? And dont tell me to get a EFI.

[Mr. Miyagi]

And dont tell me to get a EFI.

Don't you hate it when you already know the answer.......

Me, I hate it when Chadds right (throttle cable)...... lol

[Ken]

Jack recently put the 3000 - 6000 ft jet in his 600...and is very happy with the performance gain.



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[Chadd]

I would deffinitly rejet it if you ride at that elavation. I would even consider changing the weights. it makes all the differance in the world.

[Ken]

What if he's comfortable with his weight?

[Thrasher]

while on the carb subject, what mine does on my 600, it is always dumping fuel out of the overflow tube...I put in a new needle and float and adjusted to factory spec...but still does it, any ideas on what I can do to fix it?

[Rogue]

Float is off. Factory spec or not . I would try adjusting it a little lower. Also make sure no debris worked its way in while you were changing stuff. Could be as simple as crap in the bowl messing up the float height.

[Chadd]

Did you change the needle and seat?

[Pepe]

I would deffinitly rejet it if you ride at that elavation. I would even consider changing the weights. it makes all the differance in the world.

What jets and what weights would you recomend?