Hi all, I've got an 89 CBR1000F which turns over fine with no plugs in but very laboured with them in. I've gonefromone end of the bike to the otherwith the multimeter as per the Honda service manual, all checks out! Battery is new. Is there anything it can be but the Alternator Damper? Any advice appreciated!

 

I've just reasembled the engine, it's turning over fine (turned with power pack on bench 24 seperate occasions so far), even with the plugs in! Nothing replaced just stripped and checked damper assembly, took pictures will post later (kids football training), should have engine back in on Mon/Tue will post how in turns out then.