The following modifications where done by the previous owner who ran the bike on premix:

"Hi Mark,i put the carbs back to standard except for the main jets which are bigger because i soldered the #75 power jets up as recommended by hrc."

As the bike has the oil pump will I have to change the jets in the carb?

I have noticed that the airbox has been drilled and a standard air filter is installed.

The bike runs fine upto 10,000 rpm

any advise will be greatfully received