F4I starts fine but runs terrible

kustomheed · 03-14-2007, 6:43 PM

I hope someone here can help me with this. The bike is a 02 F4I. She starts fine most of the time but then the 2 and 3 cyclinders die off. The bike sounds like a v-twin and has no pull at all when that happends. Replaces the CDI box, spedo sensor and plugs. Still no love. Any ideas would be great. Thanks

tuffy6969 · 03-14-2007, 10:13 PM

What do you mean by "die off"? Does it happen at low speed?

kustomheed · 03-15-2007, 11:46 AM

It happens at all speeds. Once it warms up it just runs slow. Has no quickness to it. I will have the throttle pulled all the way back and it just doesn't go. It has a hard time getting up to 40.

tuffy6969 · 03-15-2007, 11:50 AM

Quote:

Originally Posted by kustomheed

It happens at all speeds. Once it warms up it just runs slow. Has no quickness to it. I will have the throttle pulled all the way back and it just doesn't go. It has a hard time getting up to 40.

That does not sound good at all. I have a little bit of info on similar problems and what to look for. I'll get back with you after I get off of work.

LITEITUP · 03-17-2007, 11:37 AM

check the fuel injectors maybe?

tuffy6969 · 03-17-2007, 11:58 AM

Quote:

Originally Posted by LITEITUP

check the fuel injectors maybe?

There could be several issues with the bike. From what you have said - here are some of the things that could cause it:

1. Ignition timing.
2. Check your ECM (computer)
3. Fuel flow & Injectors

You could have a stuck valve or bad valve timing. My recommendation would be to get it to a good mechanic (preferably one that knows Hondas) and have it checked out. It might be something simple -but my best bet is that there is something worse. Get it in right away. I wouldn't' ride it until you have it checked out first. You could be making the problem worse.

dattaway · 03-17-2007, 12:37 PM

Sounds like its running very rich. Running cold requires a very rich mixture, but a warm engine will bog down and even die at those settings. Fuel pressure may be high or your idle adjustment may be enriching too much.

LITEITUP · 03-17-2007, 12:37 PM

Quote:

Originally Posted by tuffy6969

There could be several issues with the bike.

Well ya it could be pretty much anything.

tuffy6969 · 03-17-2007, 8:43 PM

Quote:

Originally Posted by LITEITUP

Well ya it could be pretty much anything.

NOT nice....

LITEITUP · 03-17-2007, 11:08 PM

i was agreeing...

tuffy6969 · 03-18-2007, 12:58 AM

Quote:

Originally Posted by LITEITUP

i was agreeing...

Oops....

redneckF4rider · 03-19-2007, 11:36 PM

I had a problem that was very similar...I changed plugs and three out of four injectors....bike runs like a champ...word of advice, never use regular unleaded fuel, and add some injector cleaner ever so often!!! It helps!!

kustomheed · 03-23-2007, 11:24 PM

Bros, thanks for the ideas. I took it to the Honda shop and it was the fuel pressure regulator. It wasn't flushing fuel back to the tank and it just sat in the motor. It was flooding the center two cyclinders. What a pain. But $300 later and the bike runs like new. Well, better then new. I put on a Yosh Tri-oval and it sounds mean. Keep it on it tire!!! Later

tuffy6969 · 03-24-2007, 9:29 AM

Quote:

Originally Posted by kustomheed

Bros, thanks for the ideas. I took it to the Honda shop and it was the fuel pressure regulator. It wasn't flushing fuel back to the tank and it just sat in the motor. It was flooding the center two cyclinders. What a pain. But $300 later and the bike runs like new. Well, better then new. I put on a Yosh Tri-oval and it sounds mean. Keep it on it tire!!! Later

Well - I'm glad you got it fixed. I know it sucks not knwoing what's wrong with your bike!

kustomheed · 03-25-2007, 2:43 AM

Bro, the thing is that if I knew it was as simple as the fuel regulater, I could have don't that myself. With all the problems I have had with this bike and then the tinkering with my other bike.... I have a vault full of "what could be wrong with my bike" tips.

tuffy6969 · 03-25-2007, 2:02 PM

Quote:

Originally Posted by kustomheed

Bro, the thing is that if I knew it was as simple as the fuel regulater, I could have don't that myself. With all the problems I have had with this bike and then the tinkering with my other bike.... I have a vault full of "what could be wrong with my bike" tips.

I understand that. Unfortunately, most of us don't have the sophisticated training and equipment most modern shops use to diagnose problems with. There was a day when they had to diagnose by process of elimination. Now, with all the bikes being EFI and having computers on board, they just plug something in and get a diagnosis. They still use process of elimination once in a while, but by far, it's easier to diagnose now then it was then.

dattaway · 03-25-2007, 8:36 PM

I've found even with all the computer controlled devices, its still possible to look. listen, and smell. Those three senses with the help of a voltmeter and screwdriver are able to troubleshoot almost all problems.