Ok I ride normal, sometimes 55-70 depends on the mood and road I guess, I jetted the bike last year and when I did the jetting wsa so rich it was like a diesel truck goin down the road, now no black smoke and better milage but not my much, goin to tear down this winter and I get about 140 miles to a tank, hers my jetting what are the clinic gods thoughts

Needle Manufacturer: Mikuni
Needle Clip: 5
Jet Manufacturer: Mikuni
Main Jet Size: 170
Pilot Jet Size: 35
PMS Screw Manufacturer: Stock
PMS Turns Out: 2 1/2
My Elevation (ft): 650

This is a first in 5yrs that I've heard of an after market Mikuni needle. The main is fine and the stock pilot jet too. I would start with the needle clip position and go up 1 to the 4th groove (counting from blunt end). The portion of the needle that determines cruise mileage is coming out of that area faster because of the 5th groove position and you are getting more of the main jet over lap and using more gas. You can also try the pilot screw to lean it out some, but I would only do it at 1/8 a turn at a time. (in is leaner) Do one or the other and go thru a tank or 2.

I am curious on the needle tho, how do you know it's Mikuni? And if it is, is it the same length as the stock needle. Every thing makes a difference.

On both carbs that I used, stock and the 42hsr, at cruise (65, 70mph) my air/fuel ration is 14:1 and I'm at 50mpg. I wouldn't go any leaner than that for an air cooled engine. 12.5 to 12.8 AFR for WOT.

thaks for the input, now im courious how i found out it was mikuni, i had it apart last year but i dont remember now, thanks for addressing that for me but i will try to move the clip 1 position

Needle Manufacturer: Mikuni
Needle Clip: ?
Jet Manufacturer: Mikuni
Main Jet Size: 170
Pilot Jet Size: 35
PMS Screw Manufacturer: Stock
PMS Turns Out: 2 1/2
My Elevation (ft): 650



ok on the clip is it counted from the top down or bottom up i its top down im at 4 it its bottom up im at 3 on the clip, idk where i got 5 at on the needle oops but would i go up or down to try to lean me out a bit?

ok moved the clip from 4 to 3 from the top took it out wot and sounded good, andything i should look 4

Top it the blunt end .. the way it sits in the carb.

You count the grooves from top (1) to bottom (5) with 1 being leaner than 5.

You're going in the right direction.

You can't do the WOT with the clip on 3 ... it must be on 5.

If you're on 3 and it runs great then you're OK. You may still be rich on the main but you won't notice it.

Doc

so should i get a leaner main and move the clip back to 4?

The way I do it is as it's detailed in the WOT Tech Article ...

... clip on 5.

Once the main is dialed in I then keep moving the clip up until it runs like crap and then add another washer.

I then adjust the PMS.

If you have the $$$ you can have someone do a gas analysis .... much faster and more accurate.

Make sure you also check the choke cable as outlined in Musky's Tech Article.

Doc

Butter Bean wrote:



ok on the clip is it counted from the top down or bottom up i its top down im at 4 it its bottom up im at 3 on the clip, idk where i got 5 at on the needle oops but would i go up or down to try to lean me out a bit?

Clip position is counted from blunt end. the groove closest to point is the richest.

DocShadow wrote:


You can't do the WOT with the clip on 3 ... it must be on 5.



Doc

Why? I've never had to move mine. You don't think in 4th gear at WOT the needle is not fully out of the main jet if in 3rd or 4th groove? All my runs have been in 4th gear, at max 4900rpm, tech always stays 100rpm below limiter, at least the guy that I use.