Pilot Screws

hoodadooda · June 13th, 2010, 10:49 PM

So I finally decided to take the bike apart and rejet the carbs and what a pita it was to get there. It was my first time taking anything other than the rear seat off my bike and it was quite the adventure. I finally got to the carbs after hours of work and when I drilled the caps to get to the idle mixture screws, I went a little off center on one of them and when I stuck a drywall screw to pop the top off, I ended up chipping some of the metal around the pilot screw itself.
Also, I stripped a screw... but that's the least of my worries.

I WILL post pictures tomorrow, but I was wondering if any of you guys knew just how long the threaded part of the pilot screws would be.

On a side note, I was putting the airbox back and it wouldn't go far enough forward for both of the allens to go in. I got the one on the left to go in fine and the one on the right was just slightly off, so I couldn't put it back.

On the side of a side note, bike runs fine, no leaks, nothing abnormal (aside from the possible hot CDI issue which I noticed on hot days last summer), feels stronger on the top end and smoother on the low end.

kkim · June 13th, 2010, 11:00 PM

Quote:

Originally Posted by hoodadooda

I was wondering if any of you guys knew just how long the threaded part of the pilot screws would be.

why would you need to know that?

pilot jets or mixture screws?

crankinaway · June 14th, 2010, 06:46 AM

I think he means mixture screw and would like to know the depth of thread so he will know if the screw still has enough bite to prevent replacing the more costly carb body. I think he will have the best opinion on whether it is safe to ride unless we can see a picture.

HKr1 · June 14th, 2010, 07:23 AM

And it was right there in his hands, and he didnt un-screw it to find out......

g21-30 · June 14th, 2010, 08:09 AM

Yes, the rumor is true "The pilot may be screwed!"

kkim · June 14th, 2010, 12:16 PM

I've never removed the mixture screws from the ninja 250 carbs so I can't answer his question about how much threads are left.

Pictures would really help us to determine how screwed he really is, though.

hoodadooda · June 14th, 2010, 12:46 PM

Puns... lots of them here... good thing I like 'em

Sorry, had work from 7-3 Eastern Time, so I couldn't do anything right away.

Heres a pic, let me know how screwed I am.

Do I need a new carb?

randomwalk101 · June 14th, 2010, 12:47 PM

the thread of that mixture screw are on the wall (inside) of the carb. If you turn that mixture screw, you can actually back it all teh way out. The other side of that mixture screw is shaped like a needle with some holes in it. Anyways, I guess you can repair the thread with some thread maker...but if the thread is bad at the "top" and you can turn that screw 3-4 turns then you're good cuz that's basically the range you'll need to adjust..dont' need to back it up all the way out.

randomwalk101 · June 14th, 2010, 12:48 PM

oh, just saw the pic...holy crap..you cracked it?? man. well if it doesn't leak and you can adjust the screws then I guess it's "okay".

hoodadooda · June 14th, 2010, 12:54 PM

Quote:

Originally Posted by randomwalk101

oh, just saw the pic...holy crap..you cracked it?? man. well if it doesn't leak and you can adjust the screws then I guess it's "okay".

I guess the only way to find out how much thread is left is to just see how far I go without it falling out.

I may have just bought myself a new carb with this incident....

kkim · June 14th, 2010, 01:06 PM

do you still have the piece that broke off? perhaps you can use something like JB weld to get it back together?

Even w/o repair, as long as you can adjust it to where you want it and it doesn't fall out or leak, you'll be fine, I think.

The good thing is used carbs on Ebay run about $100, if it comes down to that... that's usually for a full set of 2 carbs.

HKr1 · June 14th, 2010, 01:22 PM

Guess I have to wait to get home to see the pic

kkim · June 14th, 2010, 01:26 PM

can you see it now?

g21-30 · June 14th, 2010, 02:06 PM

Aftermarket replacement mixture screws (see picture) are available here:

http://www.johnsmotorcycleparts.com/...products_id=28

HKr1 · June 14th, 2010, 02:51 PM

Quote:

Originally Posted by kkim

can you see it now?

Yeah, Ouch!

Think I would have backed it out to see what kind of threads it still had covered.

crankinaway · June 14th, 2010, 05:46 PM

I agree if you still have the piece you may be able to JB weld but if you can adjust for you needs and it don't leak....don't fix it.

On a side note can you drill out the caps with the carbs on the bike?

g21-30 · June 14th, 2010, 06:04 PM

Quote:

Originally Posted by crankinaway

On a side note can you drill out the caps with the carbs on the bike?

Yes, I did it with help of this DIY:

http://www.ninjette.org/forums/showthread.php?t=10246

randomwalk101 · June 14th, 2010, 06:14 PM

Quote:

Originally Posted by g21-30

Aftermarket replacement mixture screws (see picture) are available here:

http://www.johnsmotorcycleparts.com/...products_id=28

Does this work? It said for CVK40, ours are CVK 30??

hoodadooda · June 14th, 2010, 06:38 PM

So immediately after posting the pic, I got the urge to take my bike apart and give it the love and attention it needed so desperately. Her fairings fell right off and I got to the carbs in a shockingly short amount of time, all while putting the nuts, allens, and screws in individual bags and placing those bags with their couterparts (example: Fairing Allens sitting in a sandwich bag next to the fairings.) I got to the carbs and got a closer look at what I had carelessly done the other day.

So I did some measurements: the amount of thread I had broken off was about 3/8" and the screw has around 1/4" total of threading and 1/8" of the threads on the screw were showing at my bikes preferred idle: 2.75 turns out. I only had half of the of the threading on the screw actually locking on all sides with the threads on the walls.

The temporary solution I had in mind should work without conflicting with performance and giving me peace of mind, so I used some thread tape (locktite) and then I stuck a couple of vacuum caps over the idle mixture screws... why? out of sight, out of mind and I definitely need to keep my mind on the road when riding.

And after getting the carbs, battery, and gas tank back on... I decided to warm her up and throw on the seat for a ride. At first, I figured it'd be embarrassing to go out onto the main roads on a bike that's not usually naked, but WHATTHEHELL, so I rode her stark naked all around town.

I had too much fun with my loud pipe, solid rear blinkers, and jimmyrigged carbs.

I did do right by her in the end though and gave a thorough inspection of the carbs and a couple other things. There were no problems before, during, or after my 40 minutes of pure joy, so I guess I shouldn't worry...

Me and my headlamp.

Momaru · June 16th, 2010, 11:21 PM

Glad to see I'm not the only one that has to use a headlamp to work on the ninja (usually don't have time on the weekends, so it's after work and thus just about dark). I destroyed the threading on one of my carb diaphragm caps some time back and just managed to very very carefully superglue it back on; it's been happy since. Loctite might be your answer though, so long as you don't get any inside the actual fuel area.

hoodadooda · June 17th, 2010, 10:49 AM

Quote:

Originally Posted by Momaru

Glad to see I'm not the only one that has to use a headlamp to work on the ninja (usually don't have time on the weekends, so it's after work and thus just about dark). I destroyed the threading on one of my carb diaphragm caps some time back and just managed to very very carefully superglue it back on; it's been happy since. Loctite might be your answer though, so long as you don't get any inside the actual fuel area.

Yeah, I was pretty sure that loctite was going to be good enough, but the other day I decided to just go ahead and take off the white vacuum caps and then I saw the stains of gasoline.

A leak is present and I am almost positive that it will get worse over time, so I purchased replacement carbs off of ebay.

On the bright side, I'll have spare carb parts now.

Side note: I see why everyone hates those rubber wellnuts.

Momaru · June 17th, 2010, 11:51 AM

Oye ve! Very sorry to hear that mate, and glad it didn't do anything worse that could happen with gasoline leaking around the engine...

I'm sure you could probably make back a good chunk of the cost of your 'new' carbs if you parted out the ones you damaged to forum members (and other places too I suppose). Then again, spare parts are almost always good to have.

May I suggest drilling the mixture screws on these before mounting it on the bike?

hoodadooda · June 17th, 2010, 08:10 PM

Quote:

Originally Posted by Momaru

Oye ve! Very sorry to hear that mate, and glad it didn't do anything worse that could happen with gasoline leaking around the engine...

I'm sure you could probably make back a good chunk of the cost of your 'new' carbs if you parted out the ones you damaged to forum members (and other places too I suppose). Then again, spare parts are almost always good to have.

May I suggest drilling the mixture screws on these before mounting it on the bike?

ha, that's definitely some solid advice. Yeah, I'm going to keep the old ones for sure! Spare parts are extremely nice to have.

HKr1 · June 21st, 2010, 05:19 AM

Quote:

Originally Posted by hoodadooda

Yeah, I was pretty sure that loctite was going to be good enough, but the other day I decided to just go ahead and take off the white vacuum caps and then I saw the stains of gasoline.

A leak is present and I am almost positive that it will get worse over time,

Should be an o-ring in there

hoodadooda · June 26th, 2010, 10:03 PM

Quote:

Originally Posted by HKr1

Should be an o-ring in there

There was, but I guess it wasn't doing it's job. >.<
Regardless, everything runs fine now that I have the
"new" carbs in there and I have her tuned to what I'd consider perfect.

Pulls well just under 2k rpms and I can actually feel something in the upper rpms, so I'm very happy with this.

kkim · June 26th, 2010, 10:37 PM

how about adding your jetting specs to the database?
http://www.ninjette.org/forums/showthread.php?t=10208

June 13th, 2010, 10:49 PM	#1
hoodadooda MotorbikeLuv Name: Aaron Location: Henrico, VA Join Date: May 2010 Motorcycle(s): 2009 Kawasaki Ninja 250 (sold), 2006 Daytona 675 in Tornado Red (sold), 2007 Ninja 650 Posts: 272	Pilot Screws So I finally decided to take the bike apart and rejet the carbs and what a pita it was to get there. It was my first time taking anything other than the rear seat off my bike and it was quite the adventure. I finally got to the carbs after hours of work and when I drilled the caps to get to the idle mixture screws, I went a little off center on one of them and when I stuck a drywall screw to pop the top off, I ended up chipping some of the metal around the pilot screw itself. Also, I stripped a screw... but that's the least of my worries. I WILL post pictures tomorrow, but I was wondering if any of you guys knew just how long the threaded part of the pilot screws would be. On a side note, I was putting the airbox back and it wouldn't go far enough forward for both of the allens to go in. I got the one on the left to go in fine and the one on the right was just slightly off, so I couldn't put it back. On the side of a side note, bike runs fine, no leaks, nothing abnormal (aside from the possible hot CDI issue which I noticed on hot days last summer), feels stronger on the top end and smoother on the low end.

June 16th, 2010, 11:21 PM	#20
Momaru ninjette.org certified postwhore Name: Paul Location: Roanoke, VA Join Date: Jun 2009 Motorcycle(s): 2008 Candy Plasma Blue 250R Posts: A lot.	Glad to see I'm not the only one that has to use a headlamp to work on the ninja (usually don't have time on the weekends, so it's after work and thus just about dark). I destroyed the threading on one of my carb diaphragm caps some time back and just managed to very very carefully superglue it back on; it's been happy since. Loctite might be your answer though, so long as you don't get any inside the actual fuel area. __________________________________________________ Proud member of the Blue Army

June 17th, 2010, 11:51 AM	#22
Momaru ninjette.org certified postwhore Name: Paul Location: Roanoke, VA Join Date: Jun 2009 Motorcycle(s): 2008 Candy Plasma Blue 250R Posts: A lot.	Oye ve! Very sorry to hear that mate, and glad it didn't do anything worse that could happen with gasoline leaking around the engine... I'm sure you could probably make back a good chunk of the cost of your 'new' carbs if you parted out the ones you damaged to forum members (and other places too I suppose). Then again, spare parts are almost always good to have. May I suggest drilling the mixture screws on these before mounting it on the bike? __________________________________________________ Proud member of the Blue Army

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
BT-16 vs. Pilot Powers	almost40	Ninjettes At Speed	56	October 1st, 2014 07:33 AM
Pilot Power Q?	cliff0529	2008 - 2012 Ninja 250R Tech Talk	9	September 23rd, 2011 06:00 PM
#40 Pilot Jet	mrscbw	2008 - 2012 Ninja 250R Tech Talk	1	April 11th, 2011 11:33 AM
Experience with PILOT?	sb71	Motorcycle Gear	6	May 18th, 2010 09:05 PM
pilot jet	drstimpy	1986 - 2007 Ninja 250R Tech Talk	7	April 26th, 2010 08:03 AM

June 14th, 2010, 06:46 AM	#3
crankinaway ninjette.org member Name: Sean Location: Vancouver, BC Canada Join Date: Jun 2010 Motorcycle(s): 2010 Ninja 250R Posts: 16	I think he means mixture screw and would like to know the depth of thread so he will know if the screw still has enough bite to prevent replacing the more costly carb body. I think he will have the best opinion on whether it is safe to ride unless we can see a picture.

June 14th, 2010, 07:23 AM	#4
HKr1 IC2(SW) Name: Kerry Location: Pensacola Join Date: Nov 2008 Motorcycle(s): . Posts: A lot.	And it was right there in his hands, and he didnt un-screw it to find out......

June 14th, 2010, 08:09 AM	#5
g21-30 ninjette.org certified postwhore Name: Sam Location: Northern Virginia Join Date: Nov 2008 Motorcycle(s): Ninja 250R 2009 and ZX-12R 2000 Posts: A lot.	Yes, the rumor is true "The pilot may be screwed!"

June 14th, 2010, 12:16 PM	#6
kkim Join Date: Nov 2008 Posts: Too much.	I've never removed the mixture screws from the ninja 250 carbs so I can't answer his question about how much threads are left. Pictures would really help us to determine how screwed he really is, though.

June 14th, 2010, 12:46 PM	#7
hoodadooda MotorbikeLuv Name: Aaron Location: Henrico, VA Join Date: May 2010 Motorcycle(s): 2009 Kawasaki Ninja 250 (sold), 2006 Daytona 675 in Tornado Red (sold), 2007 Ninja 650 Posts: 272	Puns... lots of them here... good thing I like 'em Sorry, had work from 7-3 Eastern Time, so I couldn't do anything right away. Heres a pic, let me know how screwed I am. Do I need a new carb?

June 14th, 2010, 12:47 PM	#8
randomwalk101 self wrencher Name: john Location: houston Join Date: Dec 2008 Motorcycle(s): 08 250r and 07 600r Posts: A lot.	the thread of that mixture screw are on the wall (inside) of the carb. If you turn that mixture screw, you can actually back it all teh way out. The other side of that mixture screw is shaped like a needle with some holes in it. Anyways, I guess you can repair the thread with some thread maker...but if the thread is bad at the "top" and you can turn that screw 3-4 turns then you're good cuz that's basically the range you'll need to adjust..dont' need to back it up all the way out.

June 14th, 2010, 12:48 PM	#9
randomwalk101 self wrencher Name: john Location: houston Join Date: Dec 2008 Motorcycle(s): 08 250r and 07 600r Posts: A lot.	oh, just saw the pic...holy crap..you cracked it?? man. well if it doesn't leak and you can adjust the screws then I guess it's "okay".

June 14th, 2010, 01:06 PM	#11
kkim Join Date: Nov 2008 Posts: Too much.	do you still have the piece that broke off? perhaps you can use something like JB weld to get it back together? Even w/o repair, as long as you can adjust it to where you want it and it doesn't fall out or leak, you'll be fine, I think. The good thing is used carbs on Ebay run about $100, if it comes down to that... that's usually for a full set of 2 carbs.

June 14th, 2010, 01:22 PM	#12
HKr1 IC2(SW) Name: Kerry Location: Pensacola Join Date: Nov 2008 Motorcycle(s): . Posts: A lot.	Guess I have to wait to get home to see the pic

June 14th, 2010, 02:06 PM	#14
g21-30 ninjette.org certified postwhore Name: Sam Location: Northern Virginia Join Date: Nov 2008 Motorcycle(s): Ninja 250R 2009 and ZX-12R 2000 Posts: A lot.	Aftermarket replacement mixture screws (see picture) are available here: http://www.johnsmotorcycleparts.com/...products_id=28

June 14th, 2010, 05:46 PM	#16
crankinaway ninjette.org member Name: Sean Location: Vancouver, BC Canada Join Date: Jun 2010 Motorcycle(s): 2010 Ninja 250R Posts: 16	I agree if you still have the piece you may be able to JB weld but if you can adjust for you needs and it don't leak....don't fix it. On a side note can you drill out the caps with the carbs on the bike?

June 14th, 2010, 06:38 PM	#19
hoodadooda MotorbikeLuv Name: Aaron Location: Henrico, VA Join Date: May 2010 Motorcycle(s): 2009 Kawasaki Ninja 250 (sold), 2006 Daytona 675 in Tornado Red (sold), 2007 Ninja 650 Posts: 272	So immediately after posting the pic, I got the urge to take my bike apart and give it the love and attention it needed so desperately. Her fairings fell right off and I got to the carbs in a shockingly short amount of time, all while putting the nuts, allens, and screws in individual bags and placing those bags with their couterparts (example: Fairing Allens sitting in a sandwich bag next to the fairings.) I got to the carbs and got a closer look at what I had carelessly done the other day. So I did some measurements: the amount of thread I had broken off was about 3/8" and the screw has around 1/4" total of threading and 1/8" of the threads on the screw were showing at my bikes preferred idle: 2.75 turns out. I only had half of the of the threading on the screw actually locking on all sides with the threads on the walls. The temporary solution I had in mind should work without conflicting with performance and giving me peace of mind, so I used some thread tape (locktite) and then I stuck a couple of vacuum caps over the idle mixture screws... why? out of sight, out of mind and I definitely need to keep my mind on the road when riding. And after getting the carbs, battery, and gas tank back on... I decided to warm her up and throw on the seat for a ride. At first, I figured it'd be embarrassing to go out onto the main roads on a bike that's not usually naked, but WHATTHEHELL, so I rode her stark naked all around town. I had too much fun with my loud pipe, solid rear blinkers, and jimmyrigged carbs. I did do right by her in the end though and gave a thorough inspection of the carbs and a couple other things. There were no problems before, during, or after my 40 minutes of pure joy, so I guess I shouldn't worry... Me and my headlamp.

June 26th, 2010, 10:37 PM	#26
kkim Join Date: Nov 2008 Posts: Too much.	how about adding your jetting specs to the database? http://www.ninjette.org/forums/showthread.php?t=10208