This is an old revision of the document!
REF: Carburetor, Intake Manifold & Exhaust
Mikuni Aftermarket Carbs and Upgrades
Other than exact replacement OEM carburetors, all Mikuni aftermarket carburetors and tuning components are sold “As Is” for off road / racing use only. 1)
They are not intended or approved for use on vehicles operated on public roads or in locations where applicable engine tampering and anti-pollution laws apply.
There are plenty of Mikuni and Keihin carburetors in the market that are not authentic. 2)
They're not safe to use and will cause many problems to your bike.
If you're not sure if it's a genuine carburetor, the Sudco International site has a web page with pics of genuine and fake carbs.
Follow this link or you can call them directly to verify a seller. 3)
Also, below the series models below are notes from Sudco on fake vs genuine carbs.
Sub Documents
HSR Series:
VM Series:
HS-40
The HS40 is a Flat slide Mikuni Carb.
The stamping on mouth of this one reads “T40 6W” .
The jets included in it are in the pic to the right.
4) 
5)
Mikuni Manuals and Other Helpful Links
- Performance Guide includes:
- Air Cleaner Basics, Exhaust System Basics, Cam Basics and Ignition Basics
Video:
