does any one on here ride above 6000'?

[kix500]

if so i was just wondering what you all run for jets at this alt. sorry to bring it up again but i have seached and just can't seem to find what im looking for. i ride a 97 kx5 with reeds and a pro circit pipe with a fly wheel weight and she doesn't seem to have the big power that everyone is always talking about with theese bad boys. i and getting beat by a cr 500 and my bro's rmz 450 will stick with me. my jetting is 158 main #2on the needle 55 pilot 21/2 turns on the air screw. is my jetting close or is it the fly wheel weight killing me? oh ya the compression is 165-170psi. any suggestions?

thanks
cory

[Arigato]

Are you running in Sand?  If so, you are waaaaay to lean.

Get rid of that flywheel weight too.  Mill the head or get the Cometic high performance gasket kit.

[kix500]

does the fly wheel weight kill my power that bad? i also have it jetted to the chart and am told that that is too lean? i am way lost?


cory

[Arigato]

What surface are you riding on?

[openclass]

i would check the power value linkage, just make sure that its moving the valve when the rpms come up.

[KXcam22]

Kix,
   Lets start from scratch to get your bike figured out.  First some questions that need to be answered:

1. what gas octane and oil brand and ratio do you run?

2. what part of the country are you in, what is your base elevation that you start a ride at and how high in elevation
    do you get to (you mention 6000' - my bike runs great at 2500' but gets abit ratty over 6000').

3. What terrain do you ride mosty, ie. sand dunes, hills, single track trails.

4.  What throttle do you ride at: Be honest, wide open in dunes always, variable to low on tight trails, etc.

5. Where is your jetting right now?

Let me know and we should be able to figure something out. Cam.

[kix500]

ok thanks cam. my gas is 91oct. +1.5 bottles of outlaw oct boost to five gal of gas. i run redline oil at 40:1. my alt. is i start at bout 5500 ft but some times go to bout 7500ft. temp 75-90*f.  i like to hillclimb and trail ride mostly. some times when i can. i go to st anthony dunes. oh yea i live in hyrum ut. i usually ride between 1/2 to full throttle but i think thats is because my bike is week. i do have a welded on fly wheel weight. procicit platnum pipe, boysen reeds and cage. the silencer was choped bout 3". gearing is 14-47.
compression is 165-170 psi. power valve rod does move. but even with the fly wheel weight i just don't think my bro's rmz450 should be right with me at the dunes but espessaly on the flat. and i am getting spanked by a 97 cr 500.

jetting is
main 162
pilot 55
needle stock as far as i know in the #2 from top
airscrew 2.5 turns out
plug is br8eix iridium.

thanks
cory

[Arigato]

If you are riding in the sand, go up to a 172 main jet, clip in the #1 position.  Gear down to 14-50.  If you have an 18" rear wheel, use a 49 on the rear.  Get rid of the flywheel weight!  The heavier flywheel doesn't make the bike produce less power, it just takes longer to get there. While you're still spooling up, your friends are already there and gone.  Cometic makes a high performance gasket kit that raises the compression slightly.  This will help compensate for the altitude.

[kix500]

i just dropped the needle to #1 and the pilot from 55 to a 52 and now it feels weak. barely pics up the front tire in 1 gear. so i plan to go back to stock and start over.

cory

[Arigato]

Why did you change the pilot?  Make only one change at a time. 

[KXcam22]

Kix,
  Beause of your high elevation you are going to end up with jetting that is quite a bit leaner than most other riders on this site. You must keep this in mind since if you go on a ride trip to a much lower elevation (dunes somehwere else etc) you would have to rejet richer so as not to seize your engine. Also keep in mind to do one change at a time so you can tell if you are going in the right direction (or not).  Here's what I suggest you look at: 

Compression: For your elevation you will need to increase compression.  You should be able to set your squish band clearance to the minimum (search Doordies posts for the exact clearance, I think it is 1.3mm but better check he knows) with an alternate thinner Kaw head gasket (Check cometic too).  An easy way to measure is to bend a section of plumbing solder so it fits down the plug hole and up against the cylinder wall (where the squish is important) and kick over the engine slowly to flatten the solder.  Mic it and that is your squish.  I would suggest that your buddies CR500 has had his compression bumped.
Now to jetting: For a start stick with the 55 pilot and 162 main, it should be close.  I run 58/165 which is nice 2000-5000 but starts to get noticeably rich above 6000 -  that tells me you are in the ballpark.  Ran a 55 for a while but it got too lean when riding in snow.  For a first test you might want to drop your needle (stock N82M) all the way down and see how it responds. My recomendation would be to stick with the 55/162 and we need to find you a leaner needle that works.  At my elevation the stock needle all the way down is a bit too rich so it must be quite rich for you.  Kaw has leaner option needles or Sudco is a better source.  For needles, my rule of thumb is to go down 2 sizes then test.  Needles are cheap (at Sudco anyway) so it may speed things up to buy the next leaner 3 or 4 sizes, but still start at 2 leaner for testing.
Flywheel Weight: It will slow down the engine in a drag race, but if you hill climb or ride gnarly single track hills your bike will rule. If you can measure the dimentions of the added weight we can calulate the weight it adds.  It sounds like home made one from the previous owner.  It could possibly be way too heavy (a Steahly is 16 oz).  I had a friend who made his 32oz.
For a first test stick with 55/162 and drop the needle all the way and see how it runs.  Possibly do a 1/2 throttle plug run (use tape on the throttle for the 1/2 mark) and post the result. The procedure is usually seat of the pants testing until you get close then start doing a few plug runs a different throttle settings. It is fairly easy to tell the diff between ratty (rich -won't rev out cleanly) and flat (lean).  Let me know how it turns out. Hope this helps. Cam.

[kix500]

could someone give me the sudco part numbers for the next two leaner needles than stock for my 97 kx 5 i cant find a cross chart anywhere?


cory

[Arigato]

Flywheel Weight: It will slow down the engine in a drag race, but if you hill climb or ride gnarly single track hills your bike will rule. If you can measure the dimentions of the added weight we can calulate the weight it adds.  It sounds like home made one from the previous owner.  It could possibly be way too heavy (a Steahly is 16 oz).  I had a friend who made his 32oz.

Keep in mind that the flywheel weight only helps in hillclimbing when it's technical stuff.
For racing up a sand dune, it will hold you back.  KXcam hit the nail on the head about the compression.  Bump it up.

[kix500]

i just took my bike out yesterday for a long ride left the needle in the #2 slot didn't have time to change it pulled the plug bout 30 min into our ride makeing sure not to go above 1/2 throttle. the plug was clean all exept the electrod and the porcilin were black so i need to go leaner like you said cam. if some one could give me the next two sizes leaner numbers on the needle i will buy some. i can't find the sudo numbers. any help?

thanks guys
cory

[Rick]

been awhile since I posted, sob thought I would jump in.  what is your gearing?  are you getting beat at top speed or from corner to corner?