R100/7 Charging issues, again

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dwerbil
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R100/7 Charging issues, again

Post by dwerbil »

Last year I put on a new voltage regulator, new brushes, and a new rotor. 128k miles total on bike.

Just the other day, the red generator light is much brighter at idle. Upon revs the idiot light still stays on a bit, even to 4k rpm. Two different volt meters read barely 13 volts at 4k rpm. I've checked the battery connections and ground, cleaned the regulator plug to no avail. Ideas? Thanks in advance.
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04 R1150RT ~ 78 R100/7 ~ 84 RS ~ 93 K1100RS ~ 65 R60/2
Randy in Round Rock
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Bamboo812
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Re: R100/7 Charging issues, again

Post by Bamboo812 »

Sounds like the diode board. Instructions for testing it here: http://jhau.maliwi.de/mot/r-elec.html#diodes
dwerbil
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Re: R100/7 Charging issues, again

Post by dwerbil »

I'll check into that. Forgot to add above, new diode board last year.
Thanks Timo.
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04 R1150RT ~ 78 R100/7 ~ 84 RS ~ 93 K1100RS ~ 65 R60/2
Randy in Round Rock
Kurt in S.A.
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Re: R100/7 Charging issues, again

Post by Kurt in S.A. »

There's a specific order for the washers that keep the brush holder in place. If that was changed, that could be the source of the problem.

Kurt in S.A.
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Re: R100/7 Charging issues, again

Post by ME 109 »

Bamboo812 wrote:Sounds like the diode board. Instructions for testing it here: http://jhau.maliwi.de/mot/r-elec.html#diodes
Even with a new board, the idiot light symptoms do match a dodgy diode board.
Rob Frankham also has a good little test procedure. Somewhere.
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dwerbil
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Re: R100/7 Charging issues, again

Post by dwerbil »

Kurt in S.A. wrote:There's a specific order for the washers that keep the brush holder in place. If that was changed, that could be the source of the problem.

Kurt in S.A.
Thanks Kurt, but it had been doing fine for maybe a year now with around 13.5 volts up on the rpms.
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04 R1150RT ~ 78 R100/7 ~ 84 RS ~ 93 K1100RS ~ 65 R60/2
Randy in Round Rock
dwerbil
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Re: R100/7 Charging issues, again

Post by dwerbil »

ME 109 wrote:
Bamboo812 wrote:Sounds like the diode board. Instructions for testing it here: http://jhau.maliwi.de/mot/r-elec.html#diodes
Even with a new board, the idiot light symptoms do match a dodgy diode board.
Rob Frankham also has a good little test procedure. Somewhere.
Yes, looks like Rob was last here posting in April. Can't find anything of his site anymore. Too bad.
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SteveD
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Re: R100/7 Charging issues, again

Post by SteveD »

My understanding of the toing and froing of the electrons is scant, so my input is anecdotal.

When the GEN light on my bike started going out at higher than usual rpm ( a little over 2K, so not quite as high) it was the rotor that eventually failed within a week or two. The winding cracked under the expoxy where the red dot is.


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1982 R100RSR100RS supergallery. https://boxerboy81.smugmug.com/R100RS
2006 K1200R.
1994 R1100GS.
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SteveD
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Rob Frankcom's diode board page.

Post by SteveD »

There's a diagram or two missing from this...
edit: found Rob's stuff online...deleted the copy and paste, ignore the PM Randy. I'd suggest y'all save this to your harddrive as a doc.

http://www.frankhams.freeserve.co.uk/te ... _board.htm
Cheers, Steve
Victoria, S.E.Oz.


1982 R100RSR100RS supergallery. https://boxerboy81.smugmug.com/R100RS
2006 K1200R.
1994 R1100GS.
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Ken in Oklahoma
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Re: R100/7 Charging issues, again

Post by Ken in Oklahoma »

I'm glad you found it, Steve. It is damned good and is my go-to document. I have it on my computer, saved as HTML (I think) but being borderline computer inept I couldn't think how to get it on Boxerworks.

Ken
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