Raptor Forum banner

1 - 10 of 10 Posts

·
Registered
Joined
·
59 Posts
Discussion Starter #1
Hello,

I have my bike put back together after exhaust and intake install. I put the jets in that were recommended by the exhaust company and tuned by using the recommendations in the sticky threads. I just want to make sure everything is kosher now. It seems to be running just perfect. There is no stumble at the top of the rev so I am worried that it may be too lean. What is the check for this?
 

·
Super Moderator
Joined
·
17,060 Posts
There is no stumble so you are worried it's lean? There should be no stumble, a stumble would be a bad thing.

You have not listed your exhaust, your jetting, or your other mods so it's hard to say on spec whether your jetting is close.

A good spark plug reading will help you determine your air/fuel ratio.
 

·
Registered
Joined
·
59 Posts
Discussion Starter #3
Mike,

I have a CT Sonic with all discs, KN Intake - no box, used CTs mains (170,175) at 2.75 turns, used their needles on 4th clip, stock pilots. I feel I am pretty close with this. I am in Washington and ride down at Winchester.

I do have a slight pop at times coming off the throttle or going down gears. I am guess this may be my pilots. I have bought 25 pilots, they are Milkuni but appear different than my stock ones. Will these work with the jets and needles I have?

My other thing Mike is the spark plug test. I have read that you need to get it through all the gears and at top rev then pull the clutch and shut off the bike. That is kind of hard to do without being someone long and then working on the bike away from my garage. Is there an easier way I am missing?

Thanks for the help,

Kyle
 

·
Super Moderator
Joined
·
17,060 Posts
If you have the right pilot jet type, then yes you can run size 25 pilots with the jetting you already have. You may end up turning the fuel screws in a bit though, as more fuel will be available at idle. The pilots should resolve your issues with popping on deceleration.

Once you have those pilots in and have resolved your popping issues I'd leave it alone. Try a plug chop the next time you go riding somewhere you can actually open it up if you're still concerned, but that should be pretty close with your jetting.
 

·
Premium Member
Joined
·
2,247 Posts
Mike,

I have a CT Sonic with all discs, KN Intake - no box, used CTs mains (170,175) at 2.75 turns, used their needles on 4th clip, stock pilots. I feel I am pretty close with this. I am in Washington and ride down at Winchester.

I do have a slight pop at times coming off the throttle or going down gears. I am guess this may be my pilots. I have bought 25 pilots, they are Milkuni but appear different than my stock ones. Will these work with the jets and needles I have?

My other thing Mike is the spark plug test. I have read that you need to get it through all the gears and at top rev then pull the clutch and shut off the bike. That is kind of hard to do without being someone long and then working on the bike away from my garage. Is there an easier way I am missing?

Thanks for the help,

Kyle
Just rip up the street a few passes or in an open field at High RPM and shut the bike off on your way toward the house before it revs down to idle. You should get a pretty good read. With no air box your main jets look pretty good. I would run the needle on 2 when you switch to that set of 25 pilots and see if it doesn't come alive, needles are easy to put back if you don't like it but a lean needle will charge out of turns hard. just my 2 cents.
 

·
Registered
Joined
·
59 Posts
Discussion Starter #6
Thanks for the input everyone. Mike one more question. I bought 25 pilots at a bike shop, they are Mikunis and look different than stock. Is this normal? I thought I had read somewhere that certain brands would not work with other brands.

Thanks.
 

·
Master of the Electron
Joined
·
15,411 Posts
THey should be of the same size/shape/thread just different number (25 vs 22.5). There are several different style mikuni pilots made, make sure you have the correct ones.
 

·
Registered
Joined
·
59 Posts
Discussion Starter #8
Thanks Maniac, I did a little looking online and found that the ones the shop sold me we not the same which is what I suspected. They were the short ones so I ordered the long pilots.

ONE MORE QUESTION - how many turns should the pilots be or are those just a set thing, just screw them in all the way and they are ready to go?

Thanks, first time messing with the carb but learning lots,

Kyle
 

·
Master of the Electron
Joined
·
15,411 Posts
The pilot JETS get screwed in all the way to snug fit. The pilot SCREWS (commonly called fuel screws - outside bottom front of carb, inside a vertical hole) are adjusted to optimize the fuel flow thru the pilot jets.

The screws usually start out around 2 to 2.5 turns (CCW) from being GENTLY seated - don't tighten them in or the tip can break off. They then get adjusted to give a good, smooth idle, no hesitation when coming on throttle and little or no popping when coming off throttle.
 

·
Registered
Joined
·
59 Posts
Discussion Starter #10
Great, I will just leave the fuel screws alone and only replace the pilots. It is running pretty good now with the 22.5 pilot jets but I get some popping when letting off or down shifting.

Kyle
 
1 - 10 of 10 Posts
Top