An Unusual Problem

[Assassin8]

Hey Guys,

I have an unusual (electrical ?) problem I'm wondering if anyone else has experienced ? It's a 2000 Gen1 model. The bike runs a bit rough, although I've done all the valve clearances and synchronised the throttle bodies etc, except when I connect the dealer switch and turn it on (-00) no fault codes, the bike runs normally, very smooth idle and responsive. When I disconnect the switch, the RPM drops a round 300rpm, sort of like when you turn the headlights on on some bikes, the rpm drops and the bike runs a bit rough again... I've gone through all the wiring, but can't find fault... It has a Power Commander 3 installed, and thought it might be related to that, so I disconnected it, but that doesn't make any difference... every time I flick the dealer switch on (-00), the bike runs normally, and flick it off, idle drops a few hundred rpm, and runs slightly rough...

The charging at the battery is around 13.4V.DC at 5,000rpm, I know it should be minimum 13.8V, but not sure if that would do it... I've had other bikes with charging issues, but they don't drop rpm...

Any ideas would be greatly appreciated... Cheers Sass

 

[Hayabusa Wannabe]

Yes that voltage is low and at idle likely there is no charge and it is running off the battery at < 12.85 V.

I do not understand specifically why the rpm drops but the Hayabusa ECU is sensitive to power for operating correctly and it could just be that. Thus the charging system is a major problem so fix it then rinse, repeat and see what you are dealing with. Depending on what you know about the battery, have it load tested, and do the rectifier, stator, and short-circuit/leakage tests from the manual which will tell you which of those three parts to replace.

 

[Kiwi Rider]

Put a volt meter across the battery, now, when you switch it to dealer mode, does the charge rate/voltage at the battery increase, decrease, or stay the same?
Raise the revs to,say, 2500rpm and do the same again . . any change?

 

[groran1000]

Try disconnecting the PC3 and try it again. Let us know what you find.

 

[Berlin Germany]

@Assassin8

the gen1 have sometimes hugh issues with the connectors from generator to main harness
and at the harness to the regulator
what then ends with the followings pics. had it my self at my 1st busa.

under the tank

and at the reg. in the tail

at very 1st check those 2 pairs of conns. - eventaully they look like above and have to be replaced.

then do what kiwi already wrote - check again the voltage at batt. at diff rpms 1100 / 2500 / 5000 with low beam on.

and temporarily install a voltmeter to be able to check the charging voltage during riding the bike (heat comes in and may change the values).

my (sorry strong) advice to the 3 yellow wires from generator to the 3-point-conn. / to main harness :
read this page about my solution at a ´99 busa.
guess it will help.

and
if the charge fluctuate a lot, or rise above 14.5v install the controller of the honda cb1100xx, as described here at my page, after replacing the 4 plugs, I did it this way and now a charging voltage of 14.5 V is absolutely stable.