2000 M750 w/ black spark plugs. Got questions...

[rnicholson]

Ok. Went to take it for a ride since pulling the carbs and replacing the needle jets, and got some issues...

Idles just fine, but as soon as I give it gas it hesitates and then stalls out. Little Help?

[Howie]

Diaphragms good?  Needle position?

[rnicholson]

Diaphragms good?  Needle position?

They looked good when I looked at them earlier today...

Needles were at the 4th position (if I was looking at it right -- again new at this) 2nd position based on this diagram: .

Do I perhaps need to sync? Perhaps go back to stock -- 4th position?

[J-Cee]

To tell if your diaphragms are hole free and seated correctly open the slides by hand while engine is off. Should have some resistance. If they move freely there's a leak somewhere.

[rnicholson]

Ok. Looks like I'm all good now...

Got some time after work today to check out the needles and all. Diaphragms seem all good -- they have some push back when I try to lift them and make the nice "suction" sound I've seen in and heard in carb tuning videos on youtube.

I set the needles to 4th position (stock according the Haynes manual I got), synchronized the carbs, and now it idles even better and I can rev it without it vibrating, stalling or hesitating. It sounds 1000 times better now. 

I'm guessing previous owner was running rich cause of the worn needle jets, and just leaned it out by putting the needles to 2nd position?

Sadly, its pouring down rain here    I'd love to go take her out for a ride....

Thanks again for the advice all.