quick jetting question

[tritty_wall]

I was just wondering does the size of the main jet go up/down when your riding elev. goes up in elev. (going from 600m to 1800m) Thanks, Tristin

[blue66tang]

Ok, I just bought a 88 with no rear brakes so let me see if I can get this straight.

All I need for a 450 rear brake conversion is a:

Caliper assembly,
Brake Stay,
Rotor,
Rotor Hub,
Spacers,
Hardware,

Thats it?!

[fearlessfred]

Originally posted by tritty_wall
I was just wondering does the size of the main jet go up/down when your riding elev. goes up in elev. (going from 600m to 1800m) Thanks, Tristin up in elevation down on jet size .

From experience (from my old racing days), I can give you a quick guide line:

Main Jet size goes down with higher elevation, we used .6%-.75% in size smaller for every 1000 feet in higher elevation.
Jet Needle clip position goes down with higher elevation; like from 4th position to 3rd clip position

Air screw opening (# of turns) goes out with higher elevation; like 1 3/4 turns to 2 ½ turns, or a ¼ turn for every 1000 feet.

Carlos.

[fearlessfred]

Originally posted by acecarlos
From experience (from my old racing days), I can give you a quick guide line:

Main Jet size goes down with higher elevation, we used .6%-.75% in size smaller for every 1000 feet in higher elevation.
Jet Needle clip position goes down with higher elevation; like from 4th position to 3rd clip position

Air screw opening (# of turns) goes out with higher elevation; like 1 3/4 turns to 2 ½ turns, or a ¼ turn for every 1000 feet.

Carlos. needle clip position go up and that lowers the needle leaning it out when going up in elevation

Correct me if I am wrong fearlessfred; this is all from memory, however; I believe it is correct...

Since I no longer race, only play ride; I have no need to be this picky on my carb settings, I just error on the rich side to be safe.

Carlos.

[fearlessfred]

i wasnt really trying to correct u. just trying to clarify that the CLIP POSITION goes up to lower the needle in order to lean it out ,when going to a higher elevation and i intentionaly dont suggest jet sizing because colder temps and humidity have an effect also and those will often change when going up in elevation. i will lean my own bike out just to the point of running correctly(not blubbering ) and stop there. my time in the higher elevations is limited to 3 or 4 days ,so i dont take the time to make it perfect.

Yes this is how I remeber it: "CLIP POSITION goes up to lower the needle in order to lean it out"...

I wasn’t being factitious about being corrected; it all makes sense to me… of course these suggestions should be used as a guide line only.

Carlos.

[fearlessfred]

its all good, we are on the same page