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Discussion Starter #1
Hello
Recently purchased a 2001 Bird which has been awesome.
From purchase, it seemed to be a bit 'fuelly' at idle, but otherwise great. Until yesterday....
Whilst riding home from work, it lost power and progressively lowered its ability to rev. Like it had a reducing rev limiter.
After about 5km's, I couldn't even get it to leave the traffic lights so I pulled over. There are no warning lights at all, and temp, oil pressure etc all fine. 3/4's tank of 98 fuel.
Being new to fuel injection, I did the only thing which come to mind and that was turn it off and restarted it. It fired up fine and presented no issue for another 5kms where it started again. I shut it down whilst coasting, and rolled started it and it was fine again until I got home. It may have been an allusion, but it seemed the pipes before the mufflers were nearly red hot.
This morning it started up fine, but I'm not riding it until resolved.
My plan on the weekend it to pull and inspect the plugs, compression and leak down test it, drain the oil, inspect all the electrics etc.

So, can anyone provide any insight or direction re what I should be looking for? I've scanned the forum to see similar issues which include the fuel pressure reg?

Any help will be much appreciated as I want my Bird back on the road!

Cheers
Shedspace
 

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Interesting. I wonder if your FPR went bad. Is there evidence of gas in the oil?
Can you put a voltmeter on it temporarily and see if your voltage is staying steady?
XX

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Your spark plugs may give you a good idea what's going on. Easiest to pull them from up top but a valve clearance check would be a good idea at that mileage.
 

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Check the fuel tank vent is free. Maybe causing a vacuum as the fuel is pumped out. Easy check, when it dies, open the fuel filler and listen for air rushing in. Also, possible bad fuel pump and/or clogged fuel filter.
 

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Does it have cats and an 02 sensor?
 

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Take your spare key, open the tank lid, and try it out. If it does the same, you've ruled out the tank vent, it didn't cost a farthing, and you've gone for a ride. 3 wins.
 

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Discussion Starter #7
Thanks everyone. Will investigate more tonight. The bike is completely stock by the way.
 

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Do you notice any indicator lights dimming or flickering. My 2000 gave me a problem similar, felt like it was starving for fuel, then started running OK. Two days later it would not run when you released the starter button (i.e. headlight would come back on... as designed) then engine would stop. This was caused by poor grounds due to corrosion in the wiring harness/loom connector. Have you bypassed that connector?
 

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Discussion Starter #9
Do you notice any indicator lights dimming or flickering. My 2000 gave me a problem similar, felt like it was starving for fuel, then started running OK. Two days later it would not run when you released the starter button (i.e. headlight would come back on... as designed) then engine would stop. This was caused by poor grounds due to corrosion in the wiring harness/loom connector. Have you bypassed that connector?
Thanks for the reply. I removed the fairing last night, and I can see a lot of the wiring looks a bit second hand. Will go over it on the weekend. I put a volt meter on it last night and it was running solid at 14.4V, 13.5 at idle.
 

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Discussion Starter #10
An update. The Iridium plugs are all wet on removal. It idled for a minute or so before it went into dock. So, maybe the fuel pressure reg is an issue?
The plugs have a 2+mm gap in them. Is that normal for these plugs?
Other than the plugs, the only other issue found so far is the fuel pump connector had been arcing at some stage. Pics attached.
 

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Factory gap is supposed to be .8 to
9mm. That could well be part of your problem. Those plugs are on the verge of fuel fouling. Did you idle it until the fan cycled to get a good burn in?
 

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Iridium plugs are supposed to be changed at 45,000kms (Honda manual), some say they'll do 100,000km........ but then others say change them sooner........ but a huge gap like your plugs have just can't be good and indicates zero maintenance for a looong time....... time to do a major service I think.

While your at it, some throttle body cleaner down the holes hiding under the trumpets (they will let cleaner seep into the intake tubes just above the valves) will clean any carbon deposits that might be blocking those throttle body connecting tubes.

It's an old bike now, so it may have missed some thorough maintenance over the last few years. Make sure as Bee's has said, that there is no fuel in the oil or the engine will be damaged if it is run with diluted/polluted oil.

That voltage across the battery looks right so no reg/rect/charging issue.

Best wishes sourcing the problem...... (y)
 

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A word of wisdom. The black stuff on the blades and throttle bores is supposed to be there DO NOT REMOVE IT. It's a kind of gasket style compound that helps the throttle bodies seal better and not stick.
 
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Discussion Starter #14
Factory gap is supposed to be .8 to
9mm. That could well be part of your problem. Those plugs are on the verge of fuel fouling. Did you idle it until the fan cycled to get a good burn in?
Thanks! I'm going all over it and getting it maintenance up to spec. I agree it looks like it has not had much TLC for a while. Doing valve clearances this weekend. Cheers!
 

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Discussion Starter #15
Update
The Bird has now oil, filters, spark plugs, lash checked, coolant replaced, some hoses replaced.and everything else inspected. Compression tested with number 2 a bit lower than the others (130PSI versus 150PSI for the others (cold).
The outcome - its still is misbehaving. Symptoms largely the same - Runs fine for about 7kms, then starts surging and refusing to rev out. If you stop the engine and restart it, it will be fine, for another 5-7 km's. You can kill the engine with the red button, and roll start it and it comes good (or very near to it).
I purchased a fuel pressure gauge kit but the cheap o-ring blew out when I started it so will have to replace it.
Such a pain when the bike generally is so awesome.
 

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1. Check fuel pump for pressure and flow, may be on its last legs, also the pump wiring/fuse/relay.
2. Install a voltmeter on the dash so you can monitor voltage all the time, checking it in the shop is not enough. You may have low voltage, low enough to present symptoms. then it cools off and works again for 5 mins. Also, check all wiring/connectors on charging circuit, battery clamps and ground strap at rear of tank.
3. Check ECU for hidden codes, you never know it might lead somewhere.
 

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Discussion Starter #17
1. Check fuel pump for pressure and flow, may be on its last legs, also the pump wiring/fuse/relay.
2. Install a voltmeter on the dash so you can monitor voltage all the time, checking it in the shop is not enough. You may have low voltage, low enough to present symptoms. then it cools off and works again for 5 mins. Also, check all wiring/connectors on charging circuit, battery clamps and ground strap at rear of tank.
3. Check ECU for hidden codes, you never know it might lead somewhere.
Thanks!
 

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that cylinder down is more than 10% which is the most you want in difference. I'd be checking valve clearances. What your describing is waht sounds like the bike is going inot a safe mode because it's detecting a problem. Have you gone back in and checked the memory for FI codes? An intermittent will not keep the light on but will be stored in the systems memory. Side stand down engine idling should get it to show any codes stored.
 

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Discussion Starter #20
that cylinder down is more than 10% which is the most you want in difference. I'd be checking valve clearances. What your describing is waht sounds like the bike is going inot a safe mode because it's detecting a problem. Have you gone back in and checked the memory for FI codes? An intermittent will not keep the light on but will be stored in the systems memory. Side stand down engine idling should get it to show any codes stored.
Thanks. I assume instructions for checking the FI for faults is on the forum?
 
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