Pilot jet up, or main jet down? - Page 2

4T_Goblin · 03-29-2022, 12:42 PM

I checked the valves, exhaust was good at .005" and I tightened intake up to .003" I think it got loose to .004"

30 pilot, AF screw at 2 turns out, main 100, float bowl 21mm, tightened up screws on the intake, replaced the exhaust valve cover gasket

More tests on the horizon

4T_Goblin · 03-29-2022, 07:34 PM

The bike ride great today, no stalls at red light but the idle still gets low like 1000, occasionally to 750 but it goes back up. Still hitting 60mph. Little bit rich on the plug so here I go to fine tuning while I believe I've solved the stalling issue for now, we'll see

Bob Kelly · 03-30-2022, 04:18 AM

with your idle set so High the pilot jet is not getting to do it's job it's way up to it's upper range in RPM..... lower the idle adjust the fuel air screw for fastest idle and set the idle to 800 ~ 1000 RPM if the fuel/air screw has no effect the pilot jet is too small
install a larger one (next size up) and repeat these steps till you get a good stable idle.
....here's the thing.... it was running fine till you modified it....you changed stuff now it doesn't run fine.... but you want to keep the modified things on there so you have to change more things to make it run right again....to do this you need a real good understanding of how the carb works, what changing the exhaust has to do with changing the carburetor settings and all of that..... you are fighting yourself not the piece of machinery...put it back to stock and see if you can get it to run perfectly again then add ONE component at a time in your modifications see if that modification makes the bike run better or worse.... many times a different component will NOT improve performance but hinder it ....the people that made the bike are not stupid they used that component because it works.... you want to put on a better one but it may not work at all ..... think about it reason it out and do ONE COMPONENT at a time!
Bob....

Bob Kelly · 03-30-2022, 04:32 AM

the engine should idle fine at 500 RPM ! it doesn't have to be at 1000 RPM
but if that idle is erratic, it can die all of a sudden that is caused by the fuel/air screw not being adjusted to fastest idle speed ... then you reduce idle speed again and re do the fuel/air screw adjustment to get the fastest idle AGAIN...do this 3 or 4 times and make sure it is idling strong then set the idle to where you like it somewhere below 1500 RPM
but no faster than that. you adjust that with the other screw the idle screw not the fuel/air screw ( it just raises the slide slightly)
what your doing in adjusting the fuel/air screw is adjusting the fuel to air ratio of the engine at idle and you want it spot on at 14:1 parts air to 1 part fuel....which will give you the biggest bang when the piston comes up and it fires..... that bang can veri alot in it's boom and can be weaker or stronger because of that adjustment ...you want it as strong as you can get it.
Bob.....

Bob Kelly · 03-30-2022, 04:42 AM

I typically adjust my valves a bit loose from what the book calls for adding 1000 to the gap is not going to hurt a thing and helps when you get the engine real hot...gives it a bit more room.... those specks sound mighty tight to this old man but i don't know the bike either....4 for intake and 8 exhaust is about average but no tighter on a air cooled engine
your Ninja is water cooled and goes by a whole 'nother set of rules in both carb and valve settings and it is far more pickier... i have a 2012 Ninja 250R that is a P.I.T.A to work on....but it does run very good !
Bob.

4T_Goblin · 03-30-2022, 08:37 AM

Bob- I truly appreciate your replies. I'm absolutely not returning the bike to stock lol. I'm very close to having it tuned right.

My idle isn't that drastic, and I actually was seeing changes in the idle when adjusting the AF screw with the 30 pilot.
Through this all I had no idea what the best starting point for the idle screw was so it took me a minute to get that.
I think that .003 and .,005 are tight as I can hear them tapping still but that's what the manual and online research have led. Plus it rides fine. No stalls last night, I even leaned the pilot out an extra quarter turn. Lowered the idle some. I'm right around 1200
Plug check is due on Friday, my next day off. Then it's on to the main jet. The 100 does feel good but I believe I'm getting a slight flat spot at the end because it sounds like bwooaarrr kind of.

I'm gonna post a video link soon. I need somebody standing next to me telling me what the sound is, rich or lean lol

4T_Goblin · 04-01-2022, 04:54 PM

I checked the plug from the last ride on Tuesday and my plug was pretty white looking on half of it and rich looking on the other in the ceramic portion. I haven't seen that before

4T_Goblin · 04-02-2022, 02:38 PM

Here's a short clip going through the gears and doing some WOT

03-29-2022, 12:42 PM	#16
4T_Goblin Join Date: Jun 2021 Posts: 239	I checked the valves, exhaust was good at .005" and I tightened intake up to .003" I think it got loose to .004" 30 pilot, AF screw at 2 turns out, main 100, float bowl 21mm, tightened up screws on the intake, replaced the exhaust valve cover gasket More tests on the horizon __________________ 2020 Vader X-Pro X-7 2019 Kawasaki Ninja ex400 2022 Lifan KPX 250
	0

03-29-2022, 07:34 PM	#17
4T_Goblin Join Date: Jun 2021 Posts: 239	The bike ride great today, no stalls at red light but the idle still gets low like 1000, occasionally to 750 but it goes back up. Still hitting 60mph. Little bit rich on the plug so here I go to fine tuning while I believe I've solved the stalling issue for now, we'll see __________________ 2020 Vader X-Pro X-7 2019 Kawasaki Ninja ex400 2022 Lifan KPX 250
	0

03-30-2022, 04:18 AM	#18
Bob Kelly Join Date: Jan 2022 Location: Weed, California. Posts: 271	with your idle set so High the pilot jet is not getting to do it's job it's way up to it's upper range in RPM..... lower the idle adjust the fuel air screw for fastest idle and set the idle to 800 ~ 1000 RPM if the fuel/air screw has no effect the pilot jet is too small install a larger one (next size up) and repeat these steps till you get a good stable idle. ....here's the thing.... it was running fine till you modified it....you changed stuff now it doesn't run fine.... but you want to keep the modified things on there so you have to change more things to make it run right again....to do this you need a real good understanding of how the carb works, what changing the exhaust has to do with changing the carburetor settings and all of that..... you are fighting yourself not the piece of machinery...put it back to stock and see if you can get it to run perfectly again then add ONE component at a time in your modifications see if that modification makes the bike run better or worse.... many times a different component will NOT improve performance but hinder it ....the people that made the bike are not stupid they used that component because it works.... you want to put on a better one but it may not work at all ..... think about it reason it out and do ONE COMPONENT at a time! Bob.... __________________ It's too late when you've gone too far !
	1

03-30-2022, 04:32 AM	#19
Bob Kelly Join Date: Jan 2022 Location: Weed, California. Posts: 271	the engine should idle fine at 500 RPM ! it doesn't have to be at 1000 RPM but if that idle is erratic, it can die all of a sudden that is caused by the fuel/air screw not being adjusted to fastest idle speed ... then you reduce idle speed again and re do the fuel/air screw adjustment to get the fastest idle AGAIN...do this 3 or 4 times and make sure it is idling strong then set the idle to where you like it somewhere below 1500 RPM but no faster than that. you adjust that with the other screw the idle screw not the fuel/air screw ( it just raises the slide slightly) what your doing in adjusting the fuel/air screw is adjusting the fuel to air ratio of the engine at idle and you want it spot on at 14:1 parts air to 1 part fuel....which will give you the biggest bang when the piston comes up and it fires..... that bang can veri alot in it's boom and can be weaker or stronger because of that adjustment ...you want it as strong as you can get it. Bob..... __________________ It's too late when you've gone too far !
	1

03-30-2022, 04:42 AM	#20
Bob Kelly Join Date: Jan 2022 Location: Weed, California. Posts: 271	I typically adjust my valves a bit loose from what the book calls for adding 1000 to the gap is not going to hurt a thing and helps when you get the engine real hot...gives it a bit more room.... those specks sound mighty tight to this old man but i don't know the bike either....4 for intake and 8 exhaust is about average but no tighter on a air cooled engine your Ninja is water cooled and goes by a whole 'nother set of rules in both carb and valve settings and it is far more pickier... i have a 2012 Ninja 250R that is a P.I.T.A to work on....but it does run very good ! Bob. __________________ It's too late when you've gone too far !
	1

03-30-2022, 08:37 AM	#21
4T_Goblin Join Date: Jun 2021 Posts: 239	Bob- I truly appreciate your replies. I'm absolutely not returning the bike to stock lol. I'm very close to having it tuned right. My idle isn't that drastic, and I actually was seeing changes in the idle when adjusting the AF screw with the 30 pilot. Through this all I had no idea what the best starting point for the idle screw was so it took me a minute to get that. I think that .003 and .,005 are tight as I can hear them tapping still but that's what the manual and online research have led. Plus it rides fine. No stalls last night, I even leaned the pilot out an extra quarter turn. Lowered the idle some. I'm right around 1200 Plug check is due on Friday, my next day off. Then it's on to the main jet. The 100 does feel good but I believe I'm getting a slight flat spot at the end because it sounds like bwooaarrr kind of. I'm gonna post a video link soon. I need somebody standing next to me telling me what the sound is, rich or lean lol __________________ 2020 Vader X-Pro X-7 2019 Kawasaki Ninja ex400 2022 Lifan KPX 250
	0

04-01-2022, 04:54 PM	#22
4T_Goblin Join Date: Jun 2021 Posts: 239	I checked the plug from the last ride on Tuesday and my plug was pretty white looking on half of it and rich looking on the other in the ceramic portion. I haven't seen that before __________________ 2020 Vader X-Pro X-7 2019 Kawasaki Ninja ex400 2022 Lifan KPX 250
	0

04-02-2022, 02:38 PM	#23
4T_Goblin Join Date: Jun 2021 Posts: 239	Here's a short clip going through the gears and doing some WOT __________________ 2020 Vader X-Pro X-7 2019 Kawasaki Ninja ex400 2022 Lifan KPX 250
	0