Hey,


Just wondering if anyone has an idea of what can be going on with my 2000 cbr600f4. After being out around town the bike started to feel like it was clogged up, so i drove right home. ran some seafoam through it, checked the fuel filter, fuel pump, petcock and the strainer(filter) in the gas tank. Everything was good, other than the line from the fuel filter to fuel pump breaking and now is really short. SO after that i got the bike running and went for a short ride, everything seemed fine. I let it sit for about a week, and took it for a long ride, as soon as the bike gets nice and warm it starts again. most noticable in 2nd trying to climb in rmps, there is next to no power, the sound can be compared to somthing blocking the air flow out of the pipe and feels almost like all cylinders are not firing. I was thinking about taking the carbs apart but it seems unlikley because its only when it warms up. Plugs are new about 1000km ago. bike has higher km (43500km). thoughts?

 

also, i would say it happens about 15min after leaving the house

 

do the fuel pump test. also make sure the fuel line from the fuel tank isnt pinched.

 

How do I do the test, is the one in the repair manual the one you mean? I saw it in there but didnt really understand it. I dont think it is the line because it only happens when it gets warm, but will check it out.

 

It could be the fuel as already suggested along with the line to the fuel pump. I would replace the line to the fuel pump if its degraded at all. Sometimes, the line can delaminate inside of the hose and a piece can actaully act like a check valve stopping or slowing the fuel down. Or, with a fuel line that is degraded, it will collapse and slow down the fuel to the pump.

Another thing to consider since its about 15 minutes is to make sure your tank vent is not plugged. Take your bike for a ride, let it start to stumble and pull over. Pop your gas tank cap and listen for a swoooosh sound. If you hear it, your tank vent is plugged. If not, its probably not your problem.

you may also have a coil issue. When coils go bad, they can act up really bad once they are warm. You may have a weak coil producing a weak spark.

 

what is the best way to check the coils?

 

You can measure the resistance across all 4. Im not sure what they are supposed be, but if one is bad, it will be severely different than the others. Thats how I found a bad coil when my wife had her R6. Measure the resistance across the two pins where the clip attacheson each coil.