The float heights that you will find for the later models that use BDST carbs are complete nonsense.
See here if you are interested http://litetek.co/Guide_Mikuni_BDST_Fuel_Level.html
After you have confirmed the emulsion tubes and needles are ok, balance the carbs and set the mixture screws by ear. http://www.litetek.co/Guide_FuelScrews.html
cheers
Blair

Two very good write ups there Blair, thanks for including them.

The information on fuel levels in the Yamaha manuals leaves a great deal to be desired as you state.
Firstly a great many mistakes due to Japanese translation and secondly the use of generic diagrams from other models.
Mikuni did not help by alternating the datum line and in some cases omitting it completely.

I did not work in a dealership whilst the Fzrs were still in production but I bet the service books were considerable altered with notes by the service team.

Why Oh why did they not make the float bowls from a clear plastic material like the Lectrons of that era ?
So easy to see the level at a glance.!

Well as I recall, you helped with the missing slide housing o-rings from the BDST carbs a long time ago. Yes, lots of the parts books and manuals are exactly as you said. Honda carb seals across all their models are a labyrinth of this and that, superseded numbers, combined bits and pieces. Without the help of owners, most of them I would never sort out.

finally found the problem - previous owner did not seat the plastic tang on the needle correctly in the black slide - and the darn needles were 1.5mm higher on some carbs - fixed it all and the bike is running 1000 times better - starts and idles -


thanks - i "assumed" the stuck mixture crew was in an ok place lol - so will leave it there for a rainy day and try remove.. besides my friend has the new mix screw in switzerland so have to wait anyway :)

Good news