Runs rich and then becomes lean

Alright, I'm back with my verdict. Got the yz85 pipe welded on, engine mount holes redrilled and tapped to m8x1.25 then the bolts welded on (my bike frame doesn't have much room so everything is solid on the frame)

The pipe got rid of my 4 stroking. I think since the cylinder is naturally low compression (head is sealed on so I can't mill it down) and there is some scoring on the walls probably making it worse. I'm planning to change the jug out and get a higher compression head as soon as I get a better carb. As for now, I need to upjet because 77 is too small on my RT carb (16mm is too small, I know, I'm just waiting on the 21mm I ordered).

I have the magnet turned 20 degrees clockwise on the crank so its 20 degrees advanced from stock. I doubt it would run on 40 degrees so it must be firing stock at tdc.
WTF, you said the head is sealed on so it can't be milled down but this is a dio engine?I don't under stand,A dio on a BT jug?
 
WTF, you said the head is sealed on so it can't be milled down but this is a dio engine?I don't under stand,A dio on a BT jug?
It's a DIO reed kit. No Jug. Then I drilled 2 holes in the block to attach to the stock inlet on the jug. And I adapted the stock carb attachment to the larger inlet on the kit.
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I'm using the stock jug I got. The 2018 revision has 5mm hex bolts threaded to m6x1 instead of studs.
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Plus undersized frame. The engine mounts sheared in the block so it was drilled and retapped to m8x1.25. Bolts insterted then welded to frame. then welded exhaust to overbored stock exhaust plate. Supported with welds to the frame and brackets at chamber exit.

Power improved all over rev range (scavenging) and pipe comes on at about 6500 rpm (supercharging). The header length extended about 3 inches. Any longer and I hit the wheel. My goal isn't really to make the fastest bike on the block. I need a bike that can get me up hills yet be able to keep up with traffic at speed. First goal has been accomplished-ish (I seriously need compression badly though). The larger carb should reduce the bottleneck at high speed.
 
The 2018 revision has 5mm hex bolts threaded to m6x1 instead of studs. You did this?
Nope, that's how it came stock. No head gasket, only a bottom gasket. The stock bolts sheared so they were replaced with longer, stronger bolts. The mounting studs sheared, then over tapped as mentioned. But I did bolt the Reed to the jug. That's all my fault.
 
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