Hallo brothers. I have sporty 883 -1987 year.
Ive bought mikuni hs40 carb. And now I have problem.
Carb fits but engine is not working good. Ive tried to adjust but needle is maximum down.
Engine starts without choke and I have black smoke out of mufflers.
I think the problem is with jets. this carb is for 1200 and up.
I have 883 -
My main jet is 165, pilot jet 17.5.
What jets must I buy?

 

Nobody have Sportster 883 with MIKUNI CARB?

 

Sounds like the carb is too big for your engine.

 

I have a Mikuni HS40 on a 883. It runs well, but I don't have everything dialed in right yet. I'm still trying to rule out timing and vacuum leak possibilities. Mine seems fine, but it when letting off the clutch starting in first I have a very tiny friction zone and it seems like the engine is starved for gas. I switched the idle jet for a 22.5 which seemed to help a little, but not much. Wish I had a stock CV to play with, but this is how I bought the bike. I'm not even sure what other mods have been done, but the jugs are stamped 883.

 

Realized after my reply that this thread was 8 years old. What did you determine to be the issue? Am I headed in the right direction, or totally wrong?

 

Here`s a link to the tuning manual for the HS40.

It`s a great carburetor, the only thing I wasn`t fond of was the throttle return spring, it was stiff...

https://www.mikuni.com/pdf/hs40_manual.pdf