Ok, well, got the carbs off. The pilots are stock 35's. The mains are not dynojets, but are 120's. The lid on the airbox is definitely drilled. I'm not sure about the float needles, but they look ok. Also, not sure if the jet needles are stock or not or what position they are in since I can't get them out. The screwdriver and hex parts are stripped.

So, here's my plan for now - seal up the holes in the airbox and go smaller on the main jets (105's) and see how it runs. Next step is to replace the float needles and seats. thoughts?

-aujax

 

NO NO NO:

My suggestions:

Leave the airbox alone, it's not worth your time and not much is going to change there. The holes drilled in the airbox are not going to change your life much. If you're really interested in going back to stock, get on ebay and save some heartache.

FIRST: The needles.

If you disassemble the carb and take the slide/needle assembly out, you SHOULD be able to get a phillips and stick it inside the black plastic slide and turn the plastic piece 1/4 turn to the LEFT, and then push the needle out from the other side. It's a click-kind-of feeling, not an "unscrew" kind of feeling.

If you look at the needles, do they curve in and get really skinny (they taper very gradually kind of like an hourglass and at the end they're about the size of a ball-point pen?)

OR: They don't taper so much, and towards the end they have a definite angular cut at the last 1/8" and make a "pyramid" shape at the end of the needle?

The "hourglass" style is probably a dynojet-style needle. Especially if you found 120s in there, that's a size that comes with the dynojet kit.

The style with the tiny "pyramid" taper at the end is stock. If you could get the needles out of the slide that would really help, but if you can't, that's ok.



REMEMBER, all this is just to really find out what you've got going on in there. If your airbox is drilled and you have DJ needles and DJ 120 jets and a Yoshi pipe, you might be in the ballpark, and maybe there's some other issue in your setup.

IF you've got the carbs out, make sure they're CLEAN as can be, and make sure all 10 holes are clear in the main jet (when you take out the whole jet.) Make sure all 8 holes in the idle jet are clear.

Take the floats out of the carb and get a little bowl or cup of gas. Put each float in the bowl of gas, and make sure both sides of the float actually "float" in the gas. Make sure the metal tab on the float is about parallel with the plastic arm of the float, that's a good starting point for "float height." Make sure the black pyramid-shaped end of the float-needle is really , really clean. Take the float-needle-seat out of the carb and clean the little plastic filter that's behind there.

Anyway, I"m rambling, but while you've got 'em out, try to find out EXACTLY what's in there, and don't waste your time on the airbox or the exhaust pipe, it's not really at the heart of your problem. Good luck!

 

yea if youre running K120's for mains with a drilled airbox and a yoshi pipe your bike is jetted properly, so this is not your problem. (Though with your current setup you could drop down to a K118 Main). But having a slightly larger main jet will not cause the problmes you described. Have you set your mixture screws yet? if not make sure you do as this controls your air to fuel ratio. (not the idle set screw). Make sure when you clean the carbs youre also blowing them out with compressed air to make sure all debris is out.


what your describing is definetly either a needle and seat issue, a float issue, or someone was messing with your fuel mixture screws way too much.

And what I meant by fuel rail was the pipes that connect the fuel line to each carb, there are 2 aluminium ones and 1 plastic in the center, make sure you pull out your needles and seats and blow compressed air up through them.

Also you dont necessarily want the metal tabs on the float to be parallel with the plastic on the floats. You want them to be adjusted to give you a float height of 9mm-1cm.

 

Thanks for all the info,

I opened the carbs up and thoroughly cleaned the float needle seats (which I had never done). They didn't look especially dirty, but I used carb cleaner, a q-tip and a pipe cleaner. I also cleaned the little screens that go with them and the float needles themselves (again). I did notice a slight ring around one or two of the float needles. I looked at the floats and they are all set at the correct height.

I did notice one of my slow jets was loose - something i may have overlooked when I initially reassembled them! (OOPS!!!) I hope this is the real source of the problem. The metal caps over the mixture screws are still in place so I'm going to assume that no one ever messed with them.

The needles have that tiny pyramid at the end - so they must be stock, right?

When i did the initial cleaning I soaked each carb overnight in carb cleaner and blew them out with compressed air, so I think I'm covered on that front.

 

Ahhh! Success!!! It always seems to be the silliest and simplest things that cause the problem! I believe it was the loose slow jet - how could I have missed that???? The bike runs amazingly now. Only problem is a little bit of backfire when i decel - must be the idle screws. Anyone know if there's any way to make a yoshi pipe quieter?