Update continued.....
For anyone "ftting" a larger diameter manifold, and bigger carb, Here are some possible time-savers.....Of course, I will have some additional modifications (adaptor plate) to make as the original carb was "aimed" straight back at the center of the frame, and the new manifold has the "to the left side 45 degree twist"... As you can see, the original manifold was longer and higher anyway, so I believe these mods will bring it back to somewhat the original positioning....
1...
The insulator plastic block from a 150cc Chinese "scooter" has a 24mm main bore.... Its attachment bolt spacing is correct for the "24mm" manifold to cylinder head joint on the 125cc Lifan horizontal engine... Slight work with a half-round mill file made port matching easy and fairly quick......
2...
I'll be using a second insulator block at the manifold to carb joint for the two reasons given above (longer/further back, and higher)....While the original block that came with the 125 Lifan probably COULD be enlarged to match the manifold, a "24mm" one is already available for a couple dollars, and it will be easier to port match without risking losing the inner lip that retains the O-ring.....
Hopefully, I'll get to mount the engine this week and tweak the mounting....
Steve