R100 Rewiring

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jimjam351
Posts: 2
Joined: Fri Aug 02, 2019 7:19 am

R100 Rewiring

Post by jimjam351 »

Hey Guys, new to the forum, I have had a r1100gs that was left to me by my father in law when he passed, anyway, I recently purchased a butchered R100 that someone has started a Cafe racer conversion on and lost interest/got out of their depth on, the wiring is a mess and I am in the process of stripping it ALL out and starting again.

My question is I am converting to motogadget instrument cluster which doesn't seem like it will handle the charging light like the old cluster (which didn't come with the bike) My understanding is the light in the cluster is just voltage sensitive to trigger it, not the old positive on both sides means no glow of the original setup, in all my reading I read somewhere the charging setup needs the load of the globe to excite the charging to start or am I barking up the wrong tree, basically wanting to know how to get the charging circuit to fire up and work, should i just put a modern rec/reg on and if so does someone have a recommendation of what to get?

the bulk of the rewire does not stress me at all aside from this.. lol

Cheers Jamie
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SteveD
Posts: 4909
Joined: Tue Aug 03, 2010 3:29 am
Location: Melbourne, Oz.

Re: R100 Rewiring

Post by SteveD »

Wilkommen. :)

Grab a coffee and read this..let us know how you go...pix are good too!.https://bmwmotorcycletech.info/genlampresistor.htm
Cheers, Steve
Victoria, S.E.Oz.


1982 R100RSR100RS supergallery. https://boxerboy81.smugmug.com/R100RS
2006 K1200R.
1994 R1100GS.
jimjam351
Posts: 2
Joined: Fri Aug 02, 2019 7:19 am

Re: R100 Rewiring

Post by jimjam351 »

wow.. just a bit of light reading.. thanks!
Roy Gavin
Posts: 400
Joined: Tue Aug 03, 2010 11:21 pm
Location: Adelaide Australia

Re: R100 Rewiring

Post by Roy Gavin »

EME have a solid state R/R including all wiring for around the same price as the wiring for the OE set up.

They also have a kit which you can fit to bypass the warning light if you stick with the stock system.

Gamatronics have a neat, low cost , warning lamp which can be set to show either charging output or battery volts if the Motogadjet does not have this function.

If you plan on aftermarket ignition and a solid state R/ R you can dispense with most of the sub harnesses,etc, in this area so just order the main loom to start - DAHIK
Adelaide, Oz. 77 R75/7. 86 R80 G/S PD, 93 R100 GS, 70 BSA B44 VS ,BMW F650 Classic
Rob Frankham
Posts: 1213
Joined: Thu Aug 26, 2010 2:11 pm
Location: Scotland UK, 20 miles from civilisation up a dead end road!
Contact:

Re: R100 Rewiring

Post by Rob Frankham »

jimjam351 wrote: Sat Aug 24, 2019 7:01 pm Hey Guys, new to the forum, I have had a r1100gs that was left to me by my father in law when he passed, anyway, I recently purchased a butchered R100 that someone has started a Cafe racer conversion on and lost interest/got out of their depth on, the wiring is a mess and I am in the process of stripping it ALL out and starting again.

My question is I am converting to motogadget instrument cluster which doesn't seem like it will handle the charging light like the old cluster (which didn't come with the bike) My understanding is the light in the cluster is just voltage sensitive to trigger it, not the old positive on both sides means no glow of the original setup, in all my reading I read somewhere the charging setup needs the load of the globe to excite the charging to start or am I barking up the wrong tree, basically wanting to know how to get the charging circuit to fire up and work, should i just put a modern rec/reg on and if so does someone have a recommendation of what to get?

the bulk of the rewire does not stress me at all aside from this.. lol

Cheers Jamie
I would suggest that, if you are concerned about the 'Motogadget' ability to handle the charge circuit functions, you contact the makers and ask them. It's a very basic part of most early regulated alternator (and DC Generator) systems, not just Bosch/BMW ones. Unfortunately, I don't know the Motogadget setup so I can't make an informed comment but I have looked at the installarion instructions which seem to be singularly unhelpful on this issue. It may be that you need to rely on the original bulb setup (which is a bit sad) and if you do, the simple answer is to wire a suitable bulb between ignition + volts and D+ on the regulator. If you want to use a LED instead of a bulb, you will need to wire a suitable resistor in parallel with the LED.

Rob
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