Scooter wont go over 30mph after 52mm BBK

[Falln2pieces]

OK, Some history first...
I have installed many BBK on my scooters over the last 20 years. I have only owned Taotaos and my previous one lasted 12,000 miles/6 years before any major problems. I have never had a problem with a big bore kit but I have only ever used 50mm.

This time, I installed a 52mm kit with the big bore head. Everything is adjusted to where I believe it should be. I also have a #98 jet that worked perfect with the 50mm BBK that was on here before a bad oil leak started.

It will run fine WOT on the stand but there is "excessive" white/blue smoke coming from under the plastic around the chain tensioner screw so Im thinking the gasket.

When I start moving, it will bog for a second, then get up to 30mph very slowly and not go any faster and start bogging again but will keep running without a problem, just will not go any faster. Before changing the kit to a 52mm from a 50mm, I was getting an average of 48mph on gps and launching pretty fast from lights.

I also put a new spark plug in, rode for about 5 blocks and came back and pulled the brand new plug to find it jet black.

Help please. This is the first problem I have had that I just cant figure out.

[whiteGIANT510]

Bad rings you're burning oil