Jetting advice for idiots!?!?

[Jimbokdx]

I have a 94 KDX 200. I am an idiot. Ok... now that the basic info is undrestood, here is my problem:

I moved from near sea level to between 3000 & 4000 feet. My bike runs really rich now (it kinda did before). I have done the air-filter box mod, boysen power reeds, and I am about to install an FMF fatty pipe and FMF silencer. I use Golden Spectro oil (one bottle to 5 gallons of gas).

Where should I start on jetting? How do I know which way to go from there? How do I know when I have arrived at where I want to be?

Thanks for any help.

Jimbo

 

[canyncarvr]

A few links for you to check out.....

First, CDave's justkdx site. He has information there including a chart that shows elevation factors for jetting changes. Also starting points for the kdx with different basic modifications.

http://justkdx.dirtrider.net

Then, some pictures of plugs that give you an idea of where to look and what you're looking at. Thanks to mr. rohrich for some pretty pics.

http://www.dirtrider.net/forums3/showthread.php?s=&threadid=60392&perpage=20&display=&pagenumber=1

And a decent article here:

http://www.strappe.com/plugs.html

So..these links tell you where to start, which way to go, and how you'll know when you 'have arrived'.

Keep in mind that NOone can tell you how to jet your bike. Well...unless they're there when you ride and tuning your bike for you. It's not something that is going to happen through this forum.

Note the pics in rohrich's posts...different plugs (type and heat range), but same bike, same day, same track, etc...different riders! His point of course is how different things can be JUST due to the rider.

Which is why only YOU can jet YOUR bike.

BTW, a WOT plug chop is the only way to determine if your main jet is proper air/fuel-wise (with the correct heat range plug). That consists of a warmed up bike, a new plug and WOT under load in as high a gear as you can for as long as you can do it.....a good 30 seconds or so. Then, while holding the throttle open, hit the kill switch and pull in the clutch. Examine your plug as per the above info. That will give you an idea as to what your main circuit is doing. The main is the jet you set first, the others through throttle response and 'seat-`o-the-pants' feel.

IF you are concerned that you are lean to start with (not likely), don't run your bike at WOT for more than a few seconds. A 30-60 second WOT run with a too-lean setup can fry your top-end.

blah blah blah....


It's not real complicated. Look through the above threads. Do some searches/looking around this forum to get an idea of what you're after.

It's the single biggest bestest favor you'll do for yourself. Nothing compares to the performance you get from a spot on jetted ride! No other modification you do will perform as well as it should if jetting is off.

Have fun!!