1977 500 GTL wiring issue

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d907ie
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1977 500 GTL wiring issue

Post by d907ie » Mon May 29, 2017 12:48 pm

I just bought this bike and it has an after market (I believe) regulator. There are 3 wires coming from the alternator, but only 2 are connected to this regulator. The 3rd (red/black) is extended and connected to positive post of battery. Bike is not charging battery, hence my search for the reason. I wanted to see if the alternator was sending enough volts and was looking for connection points (this new regulator doesn't have exposed connectors, only wires coming out). So, I see the red/black wire NOT going to the regulator and thought that was strange. Now I need help. I can't find a wiring diagram, nor any posts to help. Many thanks for any help. peace

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BevHevSteve
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Re: 1977 500 GTL wiring issue

Post by BevHevSteve » Tue May 30, 2017 2:06 pm

Image
Steve Allen (925)798-BEVL[2385] Ride'm, Don't Hide'm
Ducati/Euro Spares -> https://Store.BevelHeaven.com
Facebook > http://facebook.com/Bevel.Heaven
Twitter > http://www.Twitter.com/BevelHeaven

d907ie
Cucciolo - the Lil Pup
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Re: 1977 500 GTL wiring issue

Post by d907ie » Tue May 30, 2017 6:23 pm

Thanks, Steve! I see a couple differences between the diagram and what is in front of me, but I will see how things go while I try and make mine look like the diagram. I will let you know how I fare:-). peace

d907ie
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Re: 1977 500 GTL wiring issue

Post by d907ie » Wed May 31, 2017 12:10 pm

Steve,

I believe this is an after-market regulator that came from Bevel Heaven. Pictures show 6 wires, where the stock regulator in the diagram shows 4. Only the 2 yellow wires from the alternator are connected to the regulator. The red wire from alternator is connected to the battery...too weird.
IMG_0159 (3).JPG


IMG_0159 (3).JPG
Any ideas? peace
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IMG_0161 (3).JPG

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BevHevSteve
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Re: 1977 500 GTL wiring issue

Post by BevHevSteve » Wed May 31, 2017 12:22 pm

you can download the wire diagrams for the 2 different aftermarket regs I stock easily enough...

ESR510 https://store.bevelheaven.com/Install-G ... tructions/

Ricks https://store.bevelheaven.com/Install-G ... tructions/
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Steve Allen (925)798-BEVL[2385] Ride'm, Don't Hide'm
Ducati/Euro Spares -> https://Store.BevelHeaven.com
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d907ie
Cucciolo - the Lil Pup
Posts: 7
Joined: Mon May 29, 2017 11:39 am

Re: 1977 500 GTL wiring issue

Post by d907ie » Wed May 31, 2017 5:08 pm

Thanks, yet again, Steve!
I will make sure the set-up follows your diagram (many thanks). Back to the site with an update.....soon:-) peace

d907ie
Cucciolo - the Lil Pup
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Re: 1977 500 GTL wiring issue

Post by d907ie » Thu Aug 03, 2017 10:41 am

It must be in the air, both Italian vehicles are having electronic issues :|
On the Ducati, I am at a stand-still. There are 6 wires coming from after-market Regulator and the wiring diagram from Steve only shows 5. AND, not the same colour code. If you look above, you will see the wires. This previous owner took the 2 yellows from Alt. and joined them with the 2 from regulator. The red from alternator was left "hanging". The black from regulator goes to negative, battery. The 2 reds from regulator go to positive side of battery. The white from regulator "hangs". Since this bike is a 3-wire alternator, the previous owner must have decided to follow the 2-wire diagram.

My question, Steve: With the set-up I received the bike in, and if the alternator is good, will the battery be charging while engine runs...again, based on the wired set-up. OR, is there another wiring diagram for the regulator that shows 6 wires and what to do? Many thanks, Steve...or anyone else:-)

The Gen. light stays on and battery went down on last ride.

d907ie
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Re: 1977 500 GTL wiring issue

Post by d907ie » Sat Aug 05, 2017 8:35 am

Ah!!! I forgot all about Rick's diagram. Completed the wiring...so sorry for the last post. Not getting the alternator to charge has been frustrating and impossible to find another alt. peace

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