Electrical gremlins

discussions specific to the 750 Paso

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AmcG
Posts: 24
Joined: Wed Oct 31, 2018 8:17 pm
model: 750 Paso
year: 1985
Location: UK

Electrical gremlins

Post by AmcG »

Hi

Looking under the seat today I can see that three electrical connectors have overheated to the point of melting. I think they are wires from the regulator rectifier... any idea what might be causing this?

I am not knowledgeable about motorcycle electrics ... so keep it simple please!
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Derek
paso grand pooh-bah
Posts: 768
Joined: Thu Nov 03, 2011 10:13 am
model: 907 I.E.
year: 1994
Location: Scotland

Re: Electrical gremlins

Post by Derek »

The regulator wire carry quite a high current and oxidation of the connector surfaces will create resistance which in turn generates heat which will encourage more oxidation making the situation worse with the result that the connectors eventually burn out, the insulation melts or the resistance gets so high that no current flows. You potentially risk a fire and most certainly a non-charging battery.
Replace all the connectors on both sides of the junction with good quality items that are more than up to the electrical current requirement. Also replace any damaged wiring, again using suitably heavy duty wire.
1994 907ie
2017 Supersport 939
2015 Scrambler Classic
1982 Pantah 500SL (now sold)


Scotland
AmcG
Posts: 24
Joined: Wed Oct 31, 2018 8:17 pm
model: 750 Paso
year: 1985
Location: UK

Re: Electrical gremlins

Post by AmcG »

Thanks Derek

That is very helpful.

Anyone able to suggest a good quality connector and supplier in the UK?

This forum is super helpful... thanks Pasoists
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Derek
paso grand pooh-bah
Posts: 768
Joined: Thu Nov 03, 2011 10:13 am
model: 907 I.E.
year: 1994
Location: Scotland

Re: Electrical gremlins

Post by Derek »

I regularly deal with these firms;
http://www.vehicle-wiring-products.eu/
http://www.polevolt.co.uk/
https://kojaycat.co.uk/

Their products cover a wide range of general and specialist applications. I use whichever one has what I need at the best price at any time.
1994 907ie
2017 Supersport 939
2015 Scrambler Classic
1982 Pantah 500SL (now sold)


Scotland
AmcG
Posts: 24
Joined: Wed Oct 31, 2018 8:17 pm
model: 750 Paso
year: 1985
Location: UK

Re: Electrical gremlins

Post by AmcG »

Hi

Thanks for the links.

Replaced the melted connectors and it looked like one was broken but just touching.

Bike now not charging... so I need to try and work through that.
AmcG
Posts: 24
Joined: Wed Oct 31, 2018 8:17 pm
model: 750 Paso
year: 1985
Location: UK

Re: Electrical gremlins

Post by AmcG »

Ok... so I just want a basic charging circuit. I have bought a generic 5 wire reg/rec and connected the two yellow and red wire from the stator, linked the live and wired the ground to the battery. I have charge.

Is this ok to do? Will I combust?

Thanks in advance...
Mr. Goose
Posts: 2
Joined: Sun Feb 17, 2013 9:44 pm
model: 750 Paso
year: 1988
Location: USA

Re: Electrical gremlins

Post by Mr. Goose »

When my voltage regulator burned out right from the beginning I took a hard look and saw the potential problem of corrosion under the seat, mainly the use of dissimilar metals (aluminum mounting panel). I then ran heavy gauge (10ga) copper wire from the ground mounting bolts of all the individual components directly to the battery negative earth terminal. All these years, never another electrical problem or corrosion anywhere.
Mc tool
paso grand pooh-bah
Posts: 1874
Joined: Wed Dec 05, 2007 12:35 am
model: 906 Paso
year: 1990
Location: Newzealand

Re: Electrical gremlins

Post by Mc tool »

Things like this can be hard on the brain...because upon eyeballing the problem the solution seems so simple and obvious one wonders why it wasn't done at the factory, and then the self doubt creeps in ..."I must have got this wrong ......seems to easy " . Call me cynical but I think that at the time Ducati had nothing in the piggy bank and keeping costs down was critical to survival and thusly things were speced to scrape thru the warranty period, not to last 30 years. Replacing or upgrading (fitting relays )fried connectors is as easy as it looks .
I wish I was young again............Id be heaps smarter than last time
Mr. Goose
Posts: 2
Joined: Sun Feb 17, 2013 9:44 pm
model: 750 Paso
year: 1988
Location: USA

Re: Electrical gremlins

Post by Mr. Goose »

You are just asking for corrosion anytime aluminum is attached to steel, especially when it is being asked to carry an electrical current. Hence that aluminum mounting plate for the electrics on the 750 Paso would soon result in all kinds of electrical problems.
Mc tool
paso grand pooh-bah
Posts: 1874
Joined: Wed Dec 05, 2007 12:35 am
model: 906 Paso
year: 1990
Location: Newzealand

Re: Electrical gremlins

Post by Mc tool »

The ally plate on my Paso is used to mount all the gubbins but it is not being used as an earth, and never was.
I wish I was young again............Id be heaps smarter than last time
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