Kymco ZX50

[sidthesloth]

G'Day zombie, I would prefer to keep my original box if possible, what could I do to make that possible?

[zombie]

Cut all the baffels out, I used a dremel tool. Drill a series of 3/4-1" holes behind the element, and get a piece of Unifoam to cut a custom filter. (replaceing the oem foam) you will only need a small piece approx. 4"x2"x2". I have an open K&N type, and I rarely have trouble w/ rain, so cutting holes in yours be be even less trouble. Ps Drill a 1/4" hole at the lowest point in the box to prevent any water from collecting

[sidthesloth]

Cheers zombie, I would like to go to an open type filter but where I work it gets covered with coke breeze so an enclosed one would be preferable, I will try those mods you suggested. I have drilled the main jet to 1mm and it is doing the same as it did with the original cylinder just not getting up to speed, should I look at doing the air filter now or have I missed something. I do not know where the pilot jet is.

[zombie]

The pilot jet is the tiny jet used only for the idle circuit. You may still be too lean. What exhaust do you have?, Have you pulled the spark plug after a short full throttle run (60 seconds or a little less)

[sidthesloth]

I still have the original exhaust which may be my downfall. I have not been able to get a full throttle run yet as the engine wont rev as it should, may need to close the jet again?

[zombie]

Well the oem pipe may be your saving grace for now.  It will prevent complete scavenging of the cly. allow you to get by w/ the stock carb./air box. It may be easier to move the needle up or down to determine which way to go on the jet. Raising the needle will richen you up, and vice versa. Can you get a decent idle out of it? What happens as you rev?

[sidthesloth]

From memory the needle is not adjustable. it idles good, revs ok just bogs under load.

[sidthesloth]

Sorry, my mistake, it does bog even with no load on it, twist the throttle and it sounds snappy for the first bit then just bogs, it doesn't die just doesn't rev any more. before I drilled the jet it rode ok, until it heated. Do you think I should perhaps go back on the jet size until I can get an appropiate exhaust? Though it wont be realising it's full potential it will still be usable until I can afford the pipe and carb. If need be, I will go with a pod style filter, just mean more frequent replacement.

[zombie]

Your needle is adjustable. It should be in the center position, leaving two up, and two down. (the needle in the throttle slide). If it ran lean, and overheated, then you drilled it, and it bogs the needle may take care of everything. Drop it down two notches, meaning raise the e clip to the top of the needle. That will lower the needle into the main jet, and lean the mid range mix. Try that , and see what you get. After thought: Which carb is on there?

[sidthesloth]

Is a keihin carb.

[zombie]

It's adjustable Bro! pull the cap, pull the spring back from the slider, pop the retainer, and lower the needle. You should see an improvement in a few minutes. You will still need to do a few plug chops to get it dialed in but this will get you into the game!

[Shaka]

Hey Sid, I just pulled out my stock Kehin carb to look.  The need is not adjustable.  You could raise it about 2mm if you put a washer underneath, but no way to lower it.  So not really any help there.

[sidthesloth]

Yeah, I thought it was not adjustable, though the manual says it is.

[zombie]

I have my old one on an nc/50 and it is adjustable! HMmmmm, Take the needle to a bike shop and get  a similar taper/length that is adj. You really can't tune it right w/out an adj. needle. You know I am starting to think I do own a Beer Drinking Beaner... (I had trouble finding a throttle cable, and was told my zx was either a Canadian, or Mexican import). If you can't find one local I have a few carbs that I can pull one out of, and mail it to you. Should take what, about a week?

[sidthesloth]

Thanks for the offer, that is very generous, I appreciate it and may even take you up on it. I will see what our local shop can come up with, (we only have one).