Hey everyone,

Ok so heres the deal I really hope someone can help me out here....
I rode my bike (2002 F4i) on Sunday for a good 40 miles just for a cruise, it ran perfect not a problem in the world. When I got it home I parked it and covered it. Today (tuesday) I went home on my lunch break and rode the bike back to work. It started fine, as I coasted to the bottom of the hill and took off after stopping. The bike had what seemed to be a small misfire. If I cranked on the throttle hard she took off on all four cyclinders but if I was just trying to take off from a stop or slowly open the throttle up to cruise she had a slow responsive throttle and the exhaust has a slightly deeper tone as if it was running off of three cylinders.
This last spring I replaced all the sparkplugs with NGK platniums and cleaned the airfilter. Im running 91+ octane. The bike also had a new cam chain tensioner replaced this spring. It does have the original battery still but starts everytime without a problem.
What happened to my bike basically overnight???

 

Hi dude..

the last week I had a very similar problem.. Once spark plug was going bad.. I replaced it and I took the advantage of cleaning carb, replace oil filter and clean air filter.. Now my F3 is smoother than ever.. If i were you, I'd check sparkplug and sparkplug wires first of all..

Regards..!!

 

Yeah, Im now thinking that it may be a coil, it runs good but rough on the starts and at low rpm. When it rains or I just finish washing the bike It will run horrible. Im thinking one of the coil packs is contacting the water due to a split in the rubber and actually shorting the coil out at points. Im going to tear it down this weekend and spray it with a water bottle while is running and see if I can find the problem.

Thanks everyone