Can i use that original Weber return valve/jet in with Mikunis??? Also need to confirm, that was that return jet in return line, or in line to carburator. I think in Y-piece return pipe, but sooo long time, when i take Weber away, that i cant remember 100% it. Can i use same jet size in Mikunis? How i check that float high level, if needeed? If someone is sure about answer, then i give 10 points to him and take little

A,

You probably don't need the fuel pump with the Mikuni's so the return line is also unecessary.

I NEED original fuel pump with Mikunis, cause float bows are higher, than lowest part of fuel tank!!! With Dellortos i didnt use pump, cause gravity feed functioned(Dells were lower, than lowest point of tank), simply that way. And if use original fuel pump, then need return line to tank for that fuel, what Mikunis cant use... I need to confirm, in what line is that jet for keep right amount of fuel in carbs. I cant anymore remember, what way that Y-piece(return junction) was, when i had Weber... I am virgo and thats why i keep all things in good order and make plenty of notes, but seems, that i start to bee too old and cant rememebr all things.... But now i go to hot sauna and take some

On my 900SS that I have recently beun playing with the "Y" is in-line BEFORE the carbs and just returns to the tank freely, no jet involved. This gives full flow to the carbs but no real pressure to the bowl. I would guess that you could pinch the line slightly to create some back pressure.

I built by my own a pressure valve to install instead of the jet...
just a machined box, a spring and a bearing ball. Of course you need a screw to calibrate the spring force, but it's not such an hard work to do!

I have put the Mikunis on my 89 900SS and did not use any form of fuel restriction. I have not had any problems with excess fuel in the carbs or strange running due to excessive fuel pressure. I'm pretty sure the later bikes that have the Mikunis as standard fitment do not have a restrictor in their fuel lines. The floats in the Mikunis do a good enough job themselves.