cbr600 hurricane surging
 

I have a problem that i cannot figure out so i turn to you people for help. I have an 1989 cbr600 f1 hurricane that i am turning into a streetfighter. I will post pics soon. I have had the bike for about a year, i got it for free and the fairingswere shot so, streetfighterit is. I have installeda nice round headlight, trail tech vapor gauge, and dirt bars. I m almost redy to tear it down and paint it.

So here is the problem, the bike runs fine and has plenty of power in 1,2,and 3 gears however in 4th, 5th, and 6th the power surges nd acts like the fuel is cutting out, this started bout 3 weeks go.

Heres what i have done, I have been rifling through the posts oon here and there are al lot of good i deas. The fuel system is clean and pump and relays are working accordingly,carburetors were thoroughly cleaned and all parts are working, i have been through theelectrical system 4 or 5 times and everything is connected and working including coils and rectifier. Spark is good, plugs are new and a creamy coffee color and dry when checked. Compression tested 170-175 across all four cylinders, valves are within spec. Chain sprockets and clutch all good shape/new. Oil has been changed regularly with a filter. I hope someone can help i am just at a loss i dont know what else to check.