Okay so I have a TC88B - w/95" BBK - Ported Heads - Large Valves - Big Cams - From DUNN PERFORMANCE in CO. - yada-yada-yada - I DIG the build....

Anyways I got a so called NEW Mikuni HSR45 off eBAY - Right away I notice the Fuel Bowl screws are loose so the wrench monkey that I am decides to investigate and to my NOT so surprised eyes I see that the Float Needle Valve Assembly is missing. Ok fine so I go online and start searching for one. To my surprised eyes I find 4 options. Here is where I need your help guys. All you FI guys stay home!


I see Mikuni offers 4 options in sizes (2.3/3.5/4.2/4.5)
Which one do I get?!?!

Here is a list of the Jets I have...

MAIN (170/175/180) 175 installed
Pilot (not sure what size it is)

Thanks a bunch in advance guys!!

 

I have no idea but these guys are the ones that actually import and distribute Mikuni's, I looked on their website but so can you, if you get confused by their diagrams you can call them: Sudco (310) 637-8330 ......I saw it being a 4.2 & a 25 pilot for what you asked about on a new style 45...... old style gets a 30 pilot if I read it correctly.

 

Looking at my parts diagram...

The HSR 42 and HSR 45 use a 4.2

The HSR 48 takes a 4.5

qtrracer is correct, all this stuff is on the Sudco website, although it is far from user friendly.