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Need some help - any and all advice is welcome.

I have a 1977 DT400 that struggles to keep 55 mph (bike should be capable of 85) and misfires in the high RPM range. Things I have done to the bike:

New bore with Wiseco top end. (Bike did same thing on old top end)
Carburetor rebuilt with stock jetting.
New OEM air filter.
Exhaust burned out with propane torch.
New spark plug.
Running straight gas as oil injection has been verified as working properly.

It idles fine and revs normally in neutral. The problem seems to be when it is under load. The misfire almost sounds electrical/ignition related but I'd like other opinions before I delve into that mess. Rev limit is 7krpm and it struggles to rise above 5krpm under load - will rev to max in neutral.
 

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The first thing to get out of the way is compression vs book spec. This is how I read the shop manual. Book says 153 - 187 psi. That says I have to be within this window. If I'm 152 psi, I am out of spec, time to rebuild. If I am 188 psi, It is time to decarbon the cylinder chamber.

Home he here at home does not throw the wallet at gas and spark. I need to know who/how/WOThell went wrong with my new bore job?

Signed,
NOLTT (no on listens to turtle)
 
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