The hole through the center of the emulsion tube is .111”.

Here you can see the needle jet nested just behind the hood in the venturi.  On the earlier knockoffs, you won’t see this brass piece sticking up.  Looks like we have a quick & dirty way to see if we have the latest version.

I could see that the main airbleed on this new carburetor is significantly smaller than the original PWK knockoffs.  My PWK36, PWK38 and PWK40 all had .075” main airbleeds.  The new E-Tube carb has a .039” main airbleed.

I find the smaller main airbleed an interesting tidbit.  Some of you may recall that a few months back I did a post on modifying the older PWK knockoff by installing a replaceable main airbleed.  In that post, I achieved a better fuel curve with a .032” main airbleed and a much smaller main jet (#135).  What a coincidence.

http://suzukisavage.com/cgi-bin/YaBB.pl?num=1676333024

I recall seein on some other sites that the metering block can be difficult to seal up.  It has several air and fuel passages that interconnect, and it also has a joint between the float bowl and the venturi.  Looks like a can of worms to me.  Glad someone else figured out a way to get at the needle jet without disturbing the complicated joint.

This is the seal used between the metering block and carb body.  No thanks.  Emergency use only.  Why struggle.

The idle air screw is a bit different.  Might be easier to adjust.  The screw head is a little larger.

I measured the bore of the carb.  It’s billed as a 40mm.

But just like my current knockoff 40, it’s only 38mm.  That’s OK, I’m already havin trouble keepin things glued together with a 38mm carb, I don’t need a 40.