Is this possible?

[garyg199]

As some of you may know I have been having issues with my carbs and I've taken them off to clean them. Part of one of my issues was when I was cleaning the parts, some degreaser I used somehow stripped the varnish off of my needles. I tried to shine them up the best I could using some non abrasive metal polish as per ducatiman's advice. However. When I put them back in and tried moving the slide up with my finger it didn't seem to move so smooth. It almost sounded like the diaphragm was being pushed up from the sides of where it seats, if that makes sense? Maybe it's just because they've been out and cleaned and are pretty free of fluids or maybe I was putting pressure on them in the wrong way. It was just once or twice, if I pushed it up a certain way. If I was nice and easy about it, it seemed okay.

I'm just paranoid that the stripped needles aren't going to move properly. So my question is, is that possible? Will the needles being somewhat stripped affect the movement that much? They aren't completely stripped. Just about halfway down from the top. The taper and tip seem fine.

Let me know what you think. Thanks!

[ducatiman]

are the carbs still out and accessible? Pics of removed needles in their present condition?

You previously reported needles as darkened from a cleaner.

A couple of us, actually, suggested cleaning the needles, i with using a metal polish, which (properly done) should have returned them to shiny.

You now describe needles as being "stripped".

Is there something you are not telling us here? Did you use something abrasive?

Regardless...the needles insert into the needle jets progressively as the slides are lowered. Did you clean the needle jets? They can get spooged, but *normally* only stick needles after long dormancy, in your case unlikely.

Slides clean? Diaphragms installed carefully and correctly?

[garyg199]

Hey ducatiman. I don't mean completely stripped. They were just "dulled" I guess? I don't know how to explain it. They turned black and when I got all the black crap off it was dull under it. The parts that were affected didn't turn back to the exact shine they originally had. I will post pics asap

[ducatiman]

I'm Gordon, btw.

If thats the case, i don't think thats an issue, nor the source of your concern.

Installing the "lip" of the diaphragms correctly, clean plastic slides...thats about all you can do to assure all is well.

You are looking for "smooth action" of the slides by completely raising using fingers...then dropping...they should fall simultaneously.... smooth, no scratchiness ...semi silent except for the woosh.

[garyg199]

Well I'm getting almost like a "plunger" sound as if ,like I said, the diaphragms are coming up. I took my time putting it back together so I really don't think I seated them incorrectly. I cleaned good where the lip sits etc. I don't know maybe I'm just being paranoid and looking for issues and finding ones that aren't there. I forgot I did put them back together but I may take the lids off again so I will post pics of the needles if I do.

And I am Gary. Nice to meet you Gordon. Thanks for all the help!

[ducatiman]

yqw...a woosh of air or plunger type sound is normal "on the bench".

[garyg199]

Okay. ..The diaphragm is definitely popping up under the lid somehow. I was lifting it a few times and when I got the little "pop" like a suction pop...I lift the lid a bit and the diaphragm was up . I took the needle out,cleaned it again,cleaned the slide. No luck. What the hell is going on? This an endless nightmare! Wish I knew you before I took these off!

I've attached pictures of the needle from the right head. It looks a bit bent in the picture but it's not. It's also hard to see the damage but that's it. Tell me what ya think.

[garyg199]

Wait a minute...is it possible that I'm placing my finger over the little vent hole on the slide sometimes and the pressures pushing it up? I feel like that idiotic mistake is it lol

Nope never mind. Can't access the hole with your finger! Ugh! Kill me!

Should I try shimming the needle with a washer and raise it passed the damaged part ..maybe it won't catch on the damage if that's what's going on?

[ducatiman]

"I lift the lid a bit and the diaphragm was up "

trying to envision this scenario..therefore the slide is sticking in the up position, unable to fall? Correct?

[Motofool]

Needles are not your problem.

Remove both needles and verify that the slides move freely up and down.

The spring pushes the slide down.
The vacuum applied on top of diaphragm makes slide go up.

Link to original page on YouTube.

[garyg199]

It's not quite getting stuck, it as if it's pushing the rubber out of its seat and then coming back down and seating again. It's so weird. Like, it's sticking but it's not. If I give it 5 reps with my finger consistently..1 of the 5 times at least it will make a suction type pop like if you pulled a plunger off a tile floor (best comparison I could think of). But then it must seat itself again because if I keep pushing it , it will happen again. It's both sides too. I'll take the needles out. Would it matter if I had the needles in the wrong sides? I know they have different part numbers and I'm pretty sure I matched them up right. Unless I got the wrong right and left from the kawiparts site.

[ducatiman]

disregard the needles...focus on the slide action.

The return springs are straight..not bent?

The retainers are assembled "feet" down?

In your bench testing, pushing the slides up is actually contrary to vacuum action in real service...if you are being too aggressive, you may be creating something that would not occur in service.

Difficult to understand what is happening here via keyboard.

[garyg199]

Here's a couple more pictures. Didn't snap anything else. Nothing much to see. You can see the varnish of the other needle better though.

I think I'm just going crazy guys, I don't know. I think I'm just pushing to hard sometimes like Gordon said. When I slide it gently it's okay. If I push it up abruptly and quick, it does the thing. I think I'm just looking for problems that don't exist now because I've been having trouble lol. Jeeze. I'm gonna put them on the bike and see what happens.

One thing though...it does seem to be sliding a little rough. The friction seems to be coming from the needle jet collar. Not 100% sure but that's what I'm thinking. Not sure if this will be a big issue or not.

[ducatiman]

during your procedures did you remove the needle jets and clean them?

If so, they are zero issue.

If both slides rise completely and drop to bottom when released, zero issue.

Repeatedly, aggressively, quickly pushing them upwards is contrary to their "natural action", unnecessary and possibly damaging to the diaphragm rubbers.

The pictures of a couple needles and bodies are of course, inconclusive, proving or disproving nothing.

You are WAY overthinking this...put them on the bike and see whether you've got positive results in running.

[VaFish]

Originally Posted by ducatiman

.....
You are WAY overthinking this...put them on the bike and see whether you've got positive results in running.

And if you don't have positive results call it a day, admit your shortcomings, box the carbs up and ship them to Gordon.

(and yeah I still have a couple sets I keep meaning to box up and send to him as well)

[garyg199]

Yep. Just gonna put them back on. I did take every part out for cleaning including the needle jets. Hopefully I fixed my starting/ idling issue. I reset the mixture screws and did a bench sync so I really hope so.

I will post my results here once I get them back on

[Motofool]

Clean guides of the slides are the main thing to check.
They should be completely free to move up and down.
The fast airstream creates a lot of lateral force/friction that the vacuum must overcome.

It is easy to incorrectly install the guides of the needles upside down.

[garyg199]

Originally Posted by Motofool

Clean guides of the slides are the main thing to check.
They should be completely free to move up and down.
The fast airstream creates a lot of lateral force/friction that the vacuum must overcome.

It is easy to incorrectly install the guides of the needles upside down.

What exactly are you speaking of? Where the slides sit in the carb? Or the collar where the tips of the needles sit?

[Motofool]

Originally Posted by garyg199

What exactly are you speaking of? Where the slides sit in the carb? Or the collar where the tips of the needles sit?

The guides that are in the aluminum body, into which the harder part of the plunge slides.
Those are the horizontal slots shown in your second picture.

There are two steel barrels or cylinders into which the needles slide.
Those fall out sometimes while cleaning the carbs, but have only one correct position.

[garyg199]

Originally Posted by Motofool

The guides that are in the aluminum body, into which the harder part of the plunge slides.
Those are the horizontal slots shown in your second picture.

There are two steel barrels or cylinders into which the needles slide.
Those fall out sometimes while cleaning the carbs, but have only one correct position.

Yes,okay I understand. No they def did not fall out. I will double check anyway though that they are installed correctly

[Motofool]

Originally Posted by garyg199

.....I will double check anyway though that they are installed correctly

Those cannot be pulled up if correctly installed.

[garyg199]

You're talking about the metal piece that's basically around the slide, right? Just so were on the same page

[Motofool]

Originally Posted by garyg199

You're talking about the metal piece that's basically around the slide, right? Just so were on the same page

I am talking about what is called collar in this picture:



Please, see these links:
http://faq.ninja250.org/wiki/How_do_...n_the_carbs%3F

[garyg199]

Oh yes yes! That's what I had originally thought ! Yeah they actually did fall out in fact but I made sure they were in the right way. The one end is sort of rounded and won't poke up through the tunnel for the needle to sit right so I know they are in correctly. However, like I did mention earlier, it seemed like there was some friction coming from the needle where it sits in the collar.

[ducatiman]

pic 1-here's where the *needle jet* is installed, in this orientation. They will only install in this direction.

If you inspected, cleaned its' inside "bore", installed it correctly you have no worries.

The only other possibility of anything hanging up here would be a bent needle.

pic-2 as viewed from the venturi

[ducatiman]

gary-

Quoting you earlier "The friction seems to be coming from the needle jet collar"

Also earlier within the thread..you had posted a pic of one needle which appeared bent. You proclaimed it to be ok....are you absolutely POSITIVE?

If carbs are still off...you could temporarily switch needles and see if the problem follows.

Don't blow this off...any tiny bend in the needle will/can hang up the slide action via the needle jet. In finger testing, both slides must be free to naturally return to full "rest" position EVERY time, without "help".

Urge you to be precise here...a tiny bend in the needle could be difficult to see.

"If you leave your carbs any excuse to do them again...you will."
quote: Gordon, CCS

[InvisiBill]

There seems to be confusion about what's actually causing the slide to hang up. Just take the needle out temporarily and see if it acts the same. Maybe put some tape over the hole or something to avoid air flowing unnaturally though the new opening.

If the acts the same, the problem isn't due to the needle. If it acts different without the needle, then you know the needle is an issue.

[ducatiman]

within this thread he's actually posted 2 distinct "problems"

at the top of slide throw (the diaphragm rubber "pop")

and possible interference between needle and needle jet (referred to as collar)
towards the bottom of slide activity

Its within good spirit as a fellow forum member to try and help...
but at this point will yield to others.

[garyg199]

I think that the pop I was getting was from me pushing the slide up to hard which, as Gordon said, is unnatural to the action of the diaphragm. And I'm probably getting friction in the collar because the needle probably is just the tiniest bit bent.

Guess I'll be getting a new set of needles. Should probably just buy a whole jet kit at this point