rectifier shot - help!

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kar_the_terrible
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#11 Unread post by kar_the_terrible »

In this case, it is possible that even though your alternator/stator windings may be of the right resistance, there could possibly be a bad electrical contact.

At the current which the alternator provides (assume 1.5-2 amps), even a 0.5 ohm increase can cause a voltage drop of 0.75-1 volts. Maybe its time to look at the wiring/contacts?
'78 Yamaha XS400
'86 Yamaha Radian

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TechTMW
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#12 Unread post by TechTMW »

If you own a multimeter and hav a familiarity w/ the wiring on your bike, I can give you the rundown on testing the alternator ...

Try another mechanic - one you know is skilled w/ electrics. Alot of techs never really learn any electrical theory, the just look at the book like any DIY'er.
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kar_the_terrible
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#13 Unread post by kar_the_terrible »

On an unrelated note, I just moved to Pittsburgh (for the summer) and Im simply droolling over all the classic bikes I see on the road everyday, early 70's honda's and yamaha's. A guy from work also took me to a dealer who deals exclusively in 60's 70's japanese motorcycles.....*sigh*
'78 Yamaha XS400
'86 Yamaha Radian

pauly
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'71 R5B problem

#14 Unread post by pauly »

Thanks again everybody for your responses. :)
I can get hold of a multimeter and i have the (original) owners workshop manual, but i don't have alot of experience with the electrical side of things. In fact i'm not confident and worried i'll make the problem worse somehow. If it is the alternator windings, is that expensive to fix or should i try to secure a replacement part? What to do...what to do...? :frusty:
By the way, Kar there's a guy near me who rides an early kwaka Z1000 and man, this thing is awesome-puts my R5B to shame. Know what you mean about the classics!
Shall report again.

pauly
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electrical problem on R5B - request help checking alt.

#15 Unread post by pauly »

Well, I've borrowed a multimeter. I'd like to take up TechBMW's offer of assistance on how to go about testing the alternator please. Even though I'm not all that knowlegeable I figure what I am gonna really do that the mechanic wont?

This is a real pain in the a**, 'cos i have to drive my wife's car to work and leave her stuck at home until the bike is fixed!

Patiently waiting...

pauly
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that rectifier problem

#16 Unread post by pauly »

Just a quick end note to close the whole rectifier problem. The 'mechanic' i was dealing with insisted that the recitifer was shot, but couldn't fix it even with a replacement part - hopeless.

In the end i took the bike to a specialst who had the problem sorted and fixed in TWO DAYS!.. It was the regulator not the recitifer.

Needless to say I've spoken to my old 'mechanic' and told him what i thought of him. Then i gave him the flick. He's lost my business forever.

Anyway, the bike runs like a dream again and I'm one happy little motorcyclist!! :D :D :D

p.s. again, thanks to those thoughtful people who posted replies to my request for assistance - you are special. :wink:

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