Carb Jetting

jgimar

XS650 Addict
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hutchinson, ks.
Need some help. I have recently rebuilt my old 77 650D, and will now run a two into one carb setup. I am using a Mikuni 38mm round slide jetted as follows(from a previous recommendation). Main jet 330, Pilot jet 30, Needle jet Q2, Throttle valve 2.5, Jet needle 6DP1, and Air jet 0.5.
I am experiencing a loading up problem, happening mostly upon acceleration thru the gears. When I accelerate for example from 1st to 2nd, etc. , when you reach that point to shift, it's spattering and sputtering like it's loading up. Pulled the air filter and I have quite a bit of gas slopping around. Tried one old remedy of dropping the needle all the way but still lots of gas and still loading up.
Anyone a pro on these round slides that can give me some hints? All help appreciated
 
Is 330 main a typo? sounds HUGE, I'd be more 250 as a starting point....
This hot 750 ran good on a pair of these
the 38s on the bike
body 38 N9
N 6DP-1 3rd slot
NJ P8 166
MJ260
PJ 25
Slide 1.5
Float valve 3.3
what I have heard is jetting on one carb or two varies very little. :shrug:
What manifold are you using? Several have reported fuel pooling issues with some 2 into one manifolds.
 
Is 330 main a typo? sounds HUGE, I'd be more 250 as a starting point....
This hot 750 ran good on a pair of these
the 38s on the bike
body 38 N9
N 6DP-1 3rd slot
NJ P8 166
MJ260
PJ 25
Slide 1.5
Float valve 3.3
what I have heard is jetting on one carb or two varies very little. :shrug:
What manifold are you using? Several have reported fuel pooling issues with some 2 into one manifolds.
Thank you for the input. The 330 main stated is correct . My lay out that I listed for the jetting was taken from two different tech articles I had at the time. My manifold is a homemade job out of copper tubing. Comes straight out of the jugs about an inch, then make a 90 degree to the left side of the bike with a 45 degree to put the carb back behind my left leg. It's runnin' so I must of done something right, surprised me! I'll take your jetting advise and see what happens then get back to ya. again, thanks and if anything else comes to mind please tell me!
 
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