94'cbr f2 started by free reving after a long ride. got on the highway to go home and topped out at about 70mph, backed off the throttle a little and got more power and hit 75mph, barried the throttle and slowed to 70mph again. Everytime I would back off a little it hit a "sweet spot" and got a little more power and would take me to 75mph. almost no throttle response though. after 60mph, real slow to do anything, rides fine up till about 60 great throttle response, quick and fast acceleration barely touch the throttle and responds right away like a bike should. It stopped free reving and idle is fine but still topping out at 75mph with little throttle response after 60mph. PLEASE HELP??? thanks in advance

and yes 75 is good enough to get me where i need to go or good enough to enjoy the ride but something is obviously wrong with the F2

 

what do you have done to the bike? jetted, exhaust? when did you clean your carbs last.

 

sounds like clutch issues to me if it starts free revving, which is like its in neutral right, try maybe tightiening the clutch up at the motor side.

 

well like i said its not free revving anymore. but the throttle response over 60mph and my top end in all messed up. It started after that hallowheelie ride we went on

 

stock as far as that stuff goes. I have a new exhaust but that just went on two days ago. these problems started on Halloween. And the carbs need to be cleaned I know that. was going to do that over the winter, could that cause such a low top end??

 

it could if the main jets are clogged and not letting enough fuel through at speeds. the carbs could just be way out of whack . the reason i ask about mods is because with a more free flowing exhaust, it changes the air/fuel ratio. a slipon doesnt change it drastically but couples with dirty carbs could be the problem. if it runs ok otherwise it seems like a not enough fuel issue.

 

I'm with the mouse. A mildly lean condition will usually cause an idle increase when the bike is warm. Lean is caused by clogged jets. If you could pull some spark plugs and have a look at them, that would probably lead you in the right direction. I'd bet some are going to look super lean, or they won't look the same, or something like that that will clue you in to fueling/tuning issues.

It still has the explosive power up to 60, and then it just packs up and goes home? Or do you have to kinda ease it up to 60-70, and then it won't go any faster?

 

Had something similar and it turned out to be the air solenoid. Engine asphyxiated because it never switched to the ram air duct. The engine would peter out till the bike slowed to where it could suck in enough air. Then it'd pick up again. Rinse and repeat

Since you said it was running fine before, I'd start outside the carbs first (it'll save you a forehead slap if it isn't the carbs). F2s don't have ram air so I'd suggest checking your air box (make sure its sealed good, filter good) first, checking all the hoses are routed right and looking for a block in your air hoses.

Could be an air hose worked loose or some kid stuffed some candy corn in her when you weren't looking

 

Never rule out the possibility that a rodent took a nap on your air filter and brought its beddings in for a more comfortable snooze...