I have a 1993 cbr1000f. I've been having some problems with my bike running. My bike will start up fine and idle ok. But when I go to twist the throttle, the bike bogs a lot and then the RPM's go back up to where they should be. Then the RPM matches the throttle until I let it idle again. One the engine is over 3,000 RPM the bike will react normally. And then the same thing will happen if I get on the gas again. I'm not quite sure whats going on. I have pulled my carbs off twice and cleaned them. I have pulled out my jets and cleaned them. I synced the carbs by eye and then matched them all up using a digital caliper. I'm dying to get my bike back to being capable of riding! Someone please help me!

 

Have you tried running some seafoam or other kind of fuel injector/carb cleaner thru it? This can sometimes help clean parts u cannot get to.

 

One thing to check is the vacuum to the petcock. Apply vacuum and see if you get a strong flow of fuel out of the petcock.

 

I put in some carb cleaner into my tank about a week ago. I have only put about 30 miles since then on it. And I'm still having the problem.

 

That's what I'd be trying too. Do the symptoms appear just riding or in the stand at home? What I mean is, under load or just free reving.

Have you tried the simple stuff like opening the tank lid to see if the vent's blocked? Inlet rubbers tight and no perished areas hiding a crack?

You probably have tried those things, I'm just thinking on the keyboard.

Good luck. Keep posting and everyone will try to help.

 

So i ran my bike for about 30 minutes today with a carb cleaner added to my gas. No changes happened. I went to rev my engine today and then it took at least 5-10 seconds before it would go back down to idle. I also noticed that one cylinder was running hot, one cylinder was running warm, and the other two were running at the same temperature. Any ideas?

 

One is very lean, one is a little lean, other two sound ok.
Mixtures IMO. Check your idle jet settings too.
Are your inlet rubbers tight and no cracks ?
And they seem to be sticking and need cleaning.(again)
Carb cleaner takes longer than half an hour to work, especially if the carbs are gunked up badly.
I'd run cleaner at 3x recommended dosage for one tank and see what your results are then.......

 

I reckon it's a petcock / petcock vacuum issue like TBT mentioned before.

It's only partially getting gas.

Why not hook up an aux' gas bottle and see if it runs right ? that'd rule the petcock
in or out of the problem