Cleaning carburettor Yamaha LS3

The Yamaha LS3 has a Mikuni VM20 carburetor. It's the same as the Yamaha RS100.  As I couldn't find a repair set for the LS3 I bought the one for the RX100.

Yamaha RX100 with also a Mikuni VM20 carburettor

The only difference was the air-mix-screw being a bit shorter. If it's not working I can easily replace it with the old original one.

Carburettor repair kit Yamaha LS3 - RX100

Exploded view Yamaha LS3 carbie

This carb was in desperate need of some TLC.

Mikuni carb Yamaha LS3 - left

Mikuni carb Yamaha LS3 - right

Before I opened the carbie I cleaned the outside with wax and grease remover and with a couple of steel wool pads.

Carburettor in need of some TLC

The bottom of the bowl was filled with gunk and rust, amazing how the bike ran with all the dirt in the bowl and main jet.

Dirty float bowl Yamaha LS3 100

After cleaning the bowl and taking out the main jet and banjo bolt I took off the floater so I could take out the valve seat and needle.

New and old valve seat and needle Yamaha LS3

Carburettor nozzle

With some compressed air I cleaned all the passages and with a wooden toothpick you can reach and clean all the hard to reach corners. 

Mikuni carburettor with hand choke

Mikuni carburettor with hand choke pulled out

Mikuni carburettor with pushed choke

Original air screw  longer than new one..

As the carburettor set didn't came with a new nozzle (for some reason they almost never do) I just cleaned it and for now I'll keep the original jet needle. When the bike is running again I'll try both needles and see which one is best.

Mikuni main jet and banjo bolt

Float and new gasket Mikuni carb

Mikuni carburettor with Yamaha Reed valve

Mikuni carb attached to reed valve Yamaha LS3

Mikuni carb cleaned and ready to use