Yamaha YZF600R Thundercat (4NA1 1995) carburettors in excellent used condition as shown. These carbs are fitted with size 118 mains and size 35 slow running jets.
Restoring and riding older bikes ourselves, we know how much difference clean carbs make and we’ve been ultrasonically cleaning our own carbs for several years with great results.
Our stock of used carburettors were removed from their donor motorcycles at least 13 years ago (2007 and before) in the days before petrol turned quickly to sludge and we are nearly always astonished at how clean our carbs appear inside with their float bowls removed. To make doubly sure that these carbs are as good on the inside as we’d want them to be on one of our bikes, we’ve stripped out all of the jets, etc., ultrasonically cleaned the whole bank as a single unit, along with all of the jets and other small parts while still removed. All parts where then rinsed, dried and blown through with compressed air before being visually inspected and then carefully reassembled, ensuring that all of the components are reinstalled into the carb bodies from which they came.
While we can’t guarantee that our carbs won’t need new float bowl gaskets or other seals – and they’ll certainly benefit from properly setting up for your bike – if you look at the photos you’ll see that you’d be off to a very good start with these carburettors, and you’ll certainly avoid the time and cost of getting the professionally cleaned before fitting them to your bike.