I asked about the high revving. One of the carbs ( I think just one ) is making a spitting sound, while idling and while driving. What is that a sign of ? Thank you very much.

4 hours ago, timsz said:

I asked about the high revving. One of the carbs ( I think just one ) is making a spitting sound, while idling and while driving. What is that a sign of ? Thank you very much.

There is a great facebook group for mikuni guys.  Maybe ask there?

 

What’s the spark plug look like on that carb?

Have you checked for vacuum leaks?

Checked all fasteners are tight?

O-rings in good shape?

Enrichment valve closed(choke)?