Electrical system questions

5 posts in this topic

Morning everyone. 


I have an upcoming 2 1/2 week trip round Europe this weds and have been spending a lot of time getting my bike tip top, it's been running like a dream however last Sunday I broke down out on the road. The bike just died and the fuel pump would not prime with the ignition on.


I got the bike home in my van and after some investigation found a broken wire to the back of the ECU. Repaired this and the bike is back running again thankfully.


This little incident has knocked my confidence a bit in my bike, especially with 3500 miles of riding coming up very soon!


I thought I'd do a good check of the electrical system as it's the only thing I've not been through thoroughly on the bike.


I've cleaned and greased most of the electrical connectors. 

Looking under the tank I disconnected the stator to regulator plug and found one of the spades on the stator plug to be discoloured and close to burning out.

So a new plug, new spades and some crimping and soldering later I now have a new clean plug on my stator, connection greased and ready to go.


The regulator appears to be a finned MOSFET type. I also bought a spare one from jaws to take on my trip 'just in case'

I've also added an 8mm heatsink aluminium plate behind the reg to help dissipate the heat build up.

I thought I'd take the time to test the system at this point, readings I found were:


Battery before starting the bike 12.68v

Battery at idle 12.8v

Battery with bike running at 5000 rpm with lights on 14/13.9v 

Stator AC volts at 5000 rpm between pins - all combinations measure 60v


The question I have is does this seem ok?

I'm happy with the stator output.

I know the workshop manual states a charging voltage of 15.5v at 5000rpm

(Other bikes I've owned 14v would seem healthy)


My 14v seems a bit lowly in comparison. What does everyone else's bike produce?


I want to be sure my bike is spot on for the trip, where I'm due to encounter high heat every day, likely engine fan use and 12v auxiliary charging whilst on the road of camera batteries and phone etc.


I appreciate this is a long post but when searching for questions on the site the more information the better I find, when it comes to identifying an issue you have relative to someone else's experiences!




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14v sounds about right, to me.

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Agree all sounds healthy.


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it sound right to me as that is what I got when I replaced reg/rec and battery last year and 6k later will no problems.Go and enjoy yourself.

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Excellent, thanks guys for your replies.

That's put my mind at ease!


Funny how these things happen just before a trip, last night I went for a ride and when I got home I found oil leaking onto the header pipes.

Looked to be coming from the rocker gasket so pulled the airbox off, the pair, coils etc and dropped the rad down, turned out that one of the rocker cover bolts was loose and it was spitting oil!


Glad to have found that issue before leaving that's for sure!

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