You'd be losing half a hp and creating a lot of work to get the transmission playing nice.
Is the pto shaft 5/8 or 3/4 inch? If 3/4", a comet style cvt would bolt on without too much work. Edit: found a cars and camera guy doing a cvt install on a phatmoto
View: https://youtu.be/-ABSZqW5-FI
About 6 minutes in he starts working on it.
View: https://youtu.be/PD937mNsigM
If I remember right the stock transmission on phatmotos is a double reduction with a centrifugal clutch on the pto shaft. A little convoluted but it seems to work well enough.
Here's a honda swapped phatmoto and a 125 honda ct clone.
View: https://youtu.be/p3GG8bTrjtM
View: https://youtu.be/8wPjMnzfWEA
Wyverns 224 swap isn't a bad route but I haven't seen if he needed to mod the mounting plate.
Oh, it was a nightmare because the 224 block is slightly bigger than the 212.
The concept it is simple, hog out all the material between the front foot so it slides between the front tube.
Use a Coleman CVT riser and cut it to match the front foot.
Replace the valve cover to the slanted style.
mark the mount and drill holes for riser. slot them for wiggle room.
Use the front stock holes on bike frame. and widen them a touch, drill new holes for the back.
Buy a cone filter adapter (I don't run a filter on the road)
Buy a header pipe and wrap it with a ton of heat wrap or silicone heat tube. (you may need to re-weld for fitment)
Install CVT and a 415 sprocket.
I broke my bolt off for the drive, I'm still debating if I'm going to run this engine or not.
However, if I do, I'm switching to #35 chain.
I have a Build log I'm updating.
You *can* run the stock jackshaft, but I got severe frame shaking harmonics, its much easier.
A stock 224 will lift the front tire with my 300lbs ass on there easily to 50+mph, it's no longer a motorized bike, it damn near feels like a little motorcycle.