Hi folks. Are the float needle valves in GK76 carbs a generic Mikuni part that fits several other Suzuki's with Mikuni carb's ? What other Suzuki models float needle valves have other GK76 owners fitted to their carb's in the past ?
Will Mk 1 GSF 600 Bandit ones fit seeing as they also use the Mikuni BST33 carb bodies ? I'd like to replace the ones in my bike's carb's.

Can't really help, sorry. But are 76a BST33's? As that's what's used on my 73, and I thought they were different. BSt33 also used on some Aprilia's and BM's. Quite a popular carb.

As far as I know the 400 Bandits & GK73/76's all utilise the same carb bodies but have different internals.
Anyhoo, I had a light bulb moment yeterday. I had a look in the spares stash I got with my GK76 & found a float mount/needle valve seat. Then I found an old float needle valve from my 3XV TZR's stock 28 mm carb's to see if it fitted in the GK76 seat. Low & behold it fits perfectly, length as well as diameter. So I measured up the TZR needle valve which is 13.6 mm long from the rubber tip to the top end, (not including the sprung pin the float tang pushes against). I also measured its width at it's narrowest & got 4.4 mm's. Next I had a look on ebay for Mikuni float needle valves & found a vendor that listed Tour Max pattern one's for '91-'93 400 Bandits that are the same dimensions as the old 3XV needle valve. So ... I have four on order.

Some time ago I was trying to get one B6 back to live and leaky needle valves were suspected so I took out needles of one of my spare B4s and measured them. The dimensions were nearly identical and B4 Mikuni needles were working same as B6 Keihin needles. Neither of them worked because the problem was in leaky needle seats. But the needles both looked like they are interchangeable without problems.

The standard 33mm carbs are easy to find parts for and swap bits around between other generics of the same type. Also new and upgrade parts are available from factory pro. If it's 35mm bdst35's then you start to struggle. The main part that wears are the emulsion tubes and needles. Some great articles on the factory pro website for people trying to get to the bottom of carb problems.