Honda CBR600F - charging problems? - DP
Hi guys,

At the weekend, I went with my brother in law has to pick up his new toy - a very clean 2002 Honda CBR600F which may or may not have a problem with the charging system - I would appreciate your views. In case you're wondering why I was riding it and not him, I should explain that I have TP cover on any bike and he doesn't, so I offered to bring it back for him. It was hardly a chore - it's a lovely bike. Well, nearly...

Anyway, this thing has tiny mileage (just 3,400 from new) and has done only 220 miles between the last two MOT's. When we went to look at the bike, we noticed the battery seemed a little sluggish turning the engine over, but it fired up and ran OK, and we put it down to the bike having been sitting around.

I only did a couple of miles on the test ride - no problem at all. Did the deal, signed the paperwork and went to ride off. Noticed the battery was still a little sluggish but again, she started OK so off we went.

After a mile or so filtering and stop/start (heading out of London) with rad fan kicking in and out almost constantly), the engine suddenly cut out and the battery seemed completely flat. We jump started the bike off the car, and it fired up instantly. I did notice though that whenever the revs dropped below 3,000 RPM, I could hear the fan slow appreciably and the headlight dimmed. I rode it the rest of the way back trying to keep speed and revs up as much as possible, and it got me the 30 miles back to mine no problem at all. It also restarted fine after it was switched off.

Once my brother in law had sorted out his insurance, he took the bike out an hour or so later. He called me to say it had cut out again, and sure enough the battery was dead (the bike had been idling for a couple of minutes at a set of lights). Again, we connected a set of jump leads, the bike fired up instantly, and all seemed to be well.

I left the bike in my garage overnight connected to an Optimate III. This showed the battery as being discharged but recoverable, and the lights all went green after about an hour and a half. For the lights to go green, the battery has to pass a 30 minute low current discharge test without the voltage dropping below 12.3 volts. According to the Optimate, the battery is actually OK. He rode the bike 70 odd miles yesterday and it was fine, although again we plugged into the Optimate last night, and it showed "discharged" for about an hour, before showing fully charged and OK. This was directly after a 30 mile motorway run, which struck me as a little odd. I would expect a fully charged battery after a run like this.

Have yet to attack it with a multimeter, but does this sound like a regulator/rectifier issue (or the beginnings of one), or is it simply a slightly tired battery. It does concern me though that the battery appears to be discharging at idle, or again is this normal, and its only a tired battery showing it up.

The bike has no aftermarket alarm or accessories on it, just the standard fit HISS "chip key" immobiliser.

Would appreciate any thoughts on this one.

Honda CBR600F - charging problems? - psi
will probably need a new battery as the first port of call, have you checked the voltage across the battery when running should be about 13.5 volts but shouldnt be above about 14.7 volts and it should rise with engine RPM, if not most likely the reg/rectifier, had the reg/rec problem on my Honda VFR and it had overcharged the battery once too many times as well!
Honda CBR600F - charging problems? - tr7v8
Sounds like Battery to me, if completely knackered then no amount of charging either externally or by the alternator will resurrect it. But worth a check with a DVM to see if their is a charge from the alternator.
Honda CBR600F - charging problems? - cheddar
Sounds like the battery to me, it is taking a charge but not holding it, do you have another bike you could borrow the battery from for 24hrs?

Otherwise the charging system could be suspect, not the alternator though if the lights brighten and the fan speed increases with revs.

Re my ZRX, in traffic and with the lights on the fan runs slower at idle and speeds up when the throttle is blipped, I find setting the idle at 1200 rather than 1000 rpm helps, never drained the battery though.
Honda CBR600F - charging problems? - DP
Thank you all!

I'll check the regulator output with the multimeter as soon as I get a chance, but otherwise a new battery it is then.
Honda CBR600F - charging problems? - SjB {P}
The symptoms sound awfully like what happened after I let my Hornet 600 battery completely discharge the first winter I had the bike; I didn't ride it at all, and it sat under a dust cover for probably five months. On charging it come spring, behaviour was as you describe. If the CBR in question has only done a couple of hundred miles between MOTs, then there is a fair chance it too has experienced such a fully discharged battery.

It was this experience that prompted me to buy my Optimate III and the battery now in the bike is seven years old and going strong. Every winter or period of inactivity beyond a week or two, I hook up the umbilical cord and rest easy knowing it'll be fine.

I hope your problem is as easy to fix!

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