KX500. non sealing exhaust header pipe

[KXcam22]

WRX,
  The jetting guide is exact.  I spent 5 years fine tuning my jetting only to arrive at the exact guide settings. Treat it as the gospel for stock to almost any combination of BOLT ON performance stuff.  I had the gnarly/reed spacer/reeds/mild porting setup and it was still perfect.  The 50:1 is off the manufactureres web site.  Remember that oil burns much hotter than gas so the idea is to run the least amount of oil that still gives good lubrication.  IMO the 16:1 and 32:1 days are gone (with my dads 1950 outboard motor).  A good synthetic allows leaner mixtures for less heat with better lubrication qualities.  My outboard specifies yamalube at 100:1.  If you are concerned about the oil I can vouch for Belray MC-1 at 50:1 for a nice long engine life.  Hope this helps. Cam.

[WRXBRUMBY]

thanks cam, and the rest of you guys. You have given me confidence to have a crack. i will be doing carb this weeked i hope if time permits.

cheers for the help with the carb and jetting. im pretty good from the reeds onwards with the mechanicals and the like, its just the tuning and performance part of it that i lack. this might give me the missing piece of the jigsaw ive been waiting for thanks. 

i will let you know how i get on.

heheh soz more questions............

better to set the jetting to the colder temps or the higher range temps we have here in Aus. cause we range from 0 all the way to 40 degrees celcius (depending where you ride)

is jetting kit worth buying?

what should the plug gap be? (soz havnt got manual yet. and by the looks of it you guys have more info neways)

thanks

[Hillclimb#42]

Its just important to know where you are. If you set up for warmer temps, then you'll be lean when it cools off. It will idle higher, run better off of idle and may have pinging on top-end. If you go by your cooler temps, ( much better for engine) it may run fat during peak of the day. (Less throttle response, choppy or bogging traits will be a little worse.) Usually you can find a happy middle and adjust mixture screw to compensate for temp changes. Worse case scenario, you will be to change main jet out in the brush. If you are pinging while pinned, (leaning out) or bogging and never cleaning out while mashing it(rich) you can change the main jet pretty easy, by method I wrote about earlier.
  I only change my main for winter riding in extereme cold, so you probably won't have to mess with it much. Learn all you can about reading the colors on spark plugs. You'll be an expert in no time. By the way you really need that Owner's Manual. Guys on here are true KX experts, but that manual gives you confidence when wrenching on the parts of the bike you haven't been in before. It also lays it out in an order that makes the most sense for disassembly and reassembly. It has many lists of factory spec.s that vary from year to year.

[WRXBRUMBY]

thanks for your post hillclimber. this is all gold information. cheers.

[KXT500]

so where is this jetting chart?

[GDubb]

[barryadam]

I found the jetting guide to be "right on".  It gets you to the right carb settings immediately, which combined with the "how to start your 500" sticky somewhere around here, will make having that 500 a whole new experience.
I now have flawless carburation and guaranteed 1-kick cold starts thanks to these two tools.

Barry

[WRXBRUMBY]

AAAAAAAAAAAAAAAAAAAAAAWSOME!!!!!!!!!!!!!!!!!!!

Hey guys I had a play today and your looking at one very happy and prob soon to be one very scared little man here.

I followed all the tuition that you fellas gave me, to the money and it was spot on.

I pulled apart the carb, and to my surprise the ?Main jet? (thanks cam hehe, I wouldn?t be able to use the lingo if it weren?t for your post) had fallen out.
So I endeavored to put this back in. (cause I assumed running just off the needle jet would have made it a tad rich hehehe)

Main Jet was 165 (spot on)
Didn?t check the ?pilot jet? cause my bottom end is awesome (thanks cam again for the lingo hehe)

I then took the liberty of changing the needle clip to the third position. (needle code said R1368N, is this standard? ).

Does everyone have a little trouble with the spring or was it just me hehe.(nothing that 2 zip ties couldn?t fix  )

Now I took the old girl out after putting her back together, then she fired up first kick. (from my experience finding TDC then giving it a boot full works most every time) and it already sounded crisper.

after she was warm, I then tried a ?controlled load? acceleration (a burnout on the cement)

all I can say is OMG . I have a feeling I am in for a bit of trouble. It just sounded so strong, it was like unleashing a dragon .

If you were in Aus id buy you all a beer cheers for all your help, cant wait to test ride it for real.
And fellas its been a great welcoming from all of you, I appreciate and thank you all very much for your advice Kxcam, and Danger for you 2???.