Hello guys,

I bought a CBR 600 Fi 2002, two weeks ago and I am having one problem that I can't fix...

When I run the bike at low speed (50-60 KMH) with traffic after about 15 - 30 minutes of the bike running at 95 - 110 Celsius degrees the bike loses RPM and it stops. No FI light, red light or something is displayed it just stops.
When I try to start it, it starts and after 1-2 seconds it stops again. If you let it cool down for about 10 minutes it runs 50-100 meters and then stops again. If you let it cool down for about an hour it is working with no problem (until the same process happens).


The previous mechanic didn't put the spark plugs he should, instead he installed some regular non-iridium spark plugs (the same that I use for my cb-400 sf '91).

I changed the spark plugs to the right ones but the same problem happens.

Then I checked the ignition coils (after I found that they might cause the issue) and the 2 (on the middle) had some brown spots (their color had changed a bit) and they smelled like something electric was burned.

So I replaced the 2 bad coils and went on traffic again and of-course the problem remains...

I am really disappointed, this was my dream bike but I am thinking of selling it.......


Do you have any ideas or previous experience on what this could be?


Another tip is that after the problem occurs when you turn on the kill-switch instead of having the classic stable "BIP" sound you get a discharging "BIP" sound that fades out.


Thank you for your time and effort.

 

Try bypassing the BAS temporarily.

 

Thank you for the reply. I will definitely do that but could you explain me why you think that the BAS can cause this issue?
I mean, the issue happens when the bike's temperature gets high for a long time (possibly), if the BAS is not working properly shouldn't I get this issue more randomly?

 

It's party electrical and can heat up and lose connection. Mine was acting up after 40 min of riding. You could set your watch by when the bike cut out....

I had to consider what on the bike would shut off the fuel pump and not leave a code or anything. The BAS is designed to do just that when it's tipped over. The electric current inside generated just enough heat or whatever was going on inside to make it act like it was tipped over, and it took 40 min to do it. Let it cool for a little bit and I could get a few more minutes, let it cool completely and it's good for 40 more.

if you lose your fuel pump when it dies, I'd start by bypassing it. It's easy and free enough to do. Worth a shot anyway.

 

Wow that definitely describes my situation. I found the BAS and I am thinking of a simple and nice way to bypass it. I will test it and update the post in whatever the results are.

Something that I keep thinking is the wrong spark plugs...
Do you think that the wrong spark plugs could cause damage on the ignition coils or on other electrical parts?

The bike should use the iridium laser IMR9C-9H (NGK) but the seller did a service before he sold the bike and installed the CR8EH9 (NGK). The bike did about 1000km with those spark plugs.


Thanks again!

 

Those plugs are fine. Same plug just in a different ngk series.

bypassing it is easy. It should have a 3 wire connector. Jump the outer wires of the harness together with a paperclip. Put a piece of masking tape on it so it doesn't fall out or touch metal, and go ride it.

if it dies again, reconnect it and keep searching. If it doesn't get a new BAS.

 

Hello again, I bypassed the BAS and went for a ride. After 20 minutes city drive with 30-40 KMH the bike stopped again, same problem as before...

What I want to add here is that the bike was for long time waiting on a parking garage before the seller bought it. The seller also didn't use the bike that much, just for sort rides and small distances. The bike has just 11.000 KM and they are real (that's why I bought it).

Also I am thinking of the sound that the kill-switch is making, it is like it is fading out, what does this mean? Is there something wrong with the fuel pump maybe? Maybe the injections?

I made a quick youtube video to show you what happens, hear the sound of the kill-switch on the first 2 attempts
Thanks a lot!

 

That's just the fuel pump priming and getting to full pressure.
Do you hear the pump after it dies and you are trying to get it started?

BTW, There is no need to use the kill switch to turn the bike off. Just use the key. The more you use the switch the more likely it will have issues. It's just there for emergencies.

 

The sound that I hear when I turn the kill-switch on when the bike isn't working properly is not the same as when the bike is working properly.

Here is how is should sound like:
What do you think?

 

I gave it some more thought on my ride home. Have you checked the fuel filter, pump, pre-filter to see if it's clogged up?