RE: another darn ryobi post (ryobi performance modification, analysis and comparison)
WT-610
13.49mm
0.531102362"
It has a #34 cast into the inlet.
This is a little on the large size for the Ryobi
However it does have a power check valve and a accelerator pump
The WT-610 carb is obsolete and no longer available
The WT-29 has a 28 cast into the venturi and is the proper size for a Ryobi
It is also obsolete but has the high speed check valve and a accelerator pump which is good