Maintenance & Technical > KX500 Original
Jetting!!! Again and again and again!
gowen:
--- Quote from: Paul ---Starting Point
You guys EVER gonna figure out the search function at the top of the forums? :lol:
--- End quote ---
Paul, I'm sorry if I keep posting the same ol' same ol'. The truth is, I do use the search button and I use it often. I understand the jetting chart and use it has a VERY useful reference. I have posted in the past that I had issues and I could have, I guess, just added to the previous post from eariler this year. But, since I'm having, supposely, new problems, I thought I'd make a new post. If it is a problem, please delete this post, I already tried to find a delete icon, didn't find it.
As far as what I found searching. I seem to have RICH jetting issues. But, I (for one), don't know how to test the crank pressure. I don't think it is leaking, as I am not losing oil. But, I'd hope not, if the magneto side is leaking it would be running extremely lean. So, if it was a crank leak, doubtful, it would be on the oil side. Which I am hoping is not an issue.
Just came back from riding this summer and noticed that the bike smokes alot after trail riding, runs great up high, but seems to have some blubber. Well, Here is what I have. I am running a 45 Pilot and a 160 main jet. I am in the middle with the niedle. I have a #7 slider which is showing no damage. Also am at a 2nd turn on the air screw.
I did notice some oil in the air box inside the filter, as it seems it may have too much air filter oil. But, this is pretty cosistant. I am curious why it feels sooo rich when I have the carb almost crazy lean. I have a 52 pilot, but I feel this could just make more smoke and spooge.
I have not cared about it until now, I feel it is being a power rob as it does not respond well and does NOT idle very well and smokes ALOT.
Thanks
EDIT:
Thinking about yesterday: I thought about how the bike rides, it is very "blubbery" in the low-end, bearly idles, and smokes alot when the gas is goosed. The mid-range is clean, no smoke and on through the top-end. Very strong pull, no noticeable pings (on race fuel). I'm guessing I am lean, as without it (race fuel 100bp or vp c12) it pings and surges.
Drawing a chart of what I have: What is stock: and what the jetting chart recommends:
Assuming: Sea Level and 79-100 degrees
|My Bike|Stock|Jetting Chart|
Main Jet: |160|168|165|
Slide Cutaway: |7|7|?| <-- assuming 7
Jet Needle: |N82M|N82M|?| <-- assuming stock (N82M)
Needle Position: |3|3|3|
Pilot Jet: |45|60|58|
Air Screw: |2.0|1.5|1.5|
Float Height: |Unknown|15-17mm|Unknown| <-- I need help in this area
From the looks I feel lean. I just bumped my Pilot from a 45 to 52, even though I feel rich down low, have yet to test. Will test when I can get out of work and the rain quits. I would like to also bump the main jet to a 165 and see how that works. The air screw does not help at all, I keep at 2.0. I would like to measure the float height. Is the stock numbers ok? I pulled them from my service manual. How can I test it? They are showing a special tool, is there another way? I am maybe thinking this is the problem :idea: but don't quite know how yet.
Here is what I'm running, Boyesen Power reeds, FMF Desert pipe & silencer (powercore), egorr big bore with mid-top porting (520cc 2mm kit).
Sorry about the LOOOOOOOOOONG post, but I was told that I could be losing as much as 10-20hp potental power by having the jetting off. :?:
Paul:
When was the last time the carb was torn completely apart and cleaned? I had an issue similar to this and found some Glamis residue in the tubes that the pilot and main jets thread into. If it's been awhile since the carb was cleaned then get some pipe cleaners and some carb cleaner and see what that does for you.
gowen:
I got it apart now. I will give it a shot. Do you think by having a 45 Pilot that it was making it a PITA to start cold? :shock:
Paul:
Ummm, yeah. :lol:
--- Quote from: gowen ---I got it apart now. I will give it a shot. Do you think by having a 45 Pilot that it was making it a PITA to start cold? :shock:
--- End quote ---
This is the big bore 520 correct? You maybe looking at a 180 - 182 @ sea level for a main jet.
Sharc:
If you over-oiled your filter, it'll run rich with lean jets. And some filter oil may have found its way into your carb and gummed something up. Clean your carb out real good like Paul said, and put on a fresh lightly oiled filter just to get eliminate that as a possible cause...Paul's chart is darn close for jetting. 45 pilot is way too small. I'd guess the pilot circuit is clogged and it's sucking gas from somewhere else and loading-up your bottom end. And your reeds are ok, right...?
good luck.
Sharc
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