• Required reading for all forum users!!!

    Welcome!
    Register to access the full functionality of the GSResources forum. Until you register and activate your account you will not have full forum access, nor will you be able to post or reply to messages.

    A note to new registrants...
    All new forum registrations must be activated via email before you have full access to the forum.

    A Special Note about Email accounts!
    DO NOT SIGN UP USING hotmail, outlook, gmx, sbcglobal, att, bellsouth or email.com. They delete our forum signup emails.

    A note to old forum members...
    I receive numerous requests from people who can no longer log in because their accounts were deleted. As mentioned in the forum FAQ, user accounts are deleted if you haven't logged in for the past 6 months. If you can't log in, then create a new forum account. If you don't get an error message, then check your email account for an activation message. If you get a message stating that the email address is already in use, then your account still exists so follow the instructions in the forum FAQ for resetting your password.

    Have you forgotten your password or have a new email address? Then read the forum FAQ for details on how to reset it.

    Any email requests for "can't log in anymore" problems or "lost my password" problems will be deleted. Read the forum FAQ and follow the instructions there - that's what we have one for...

  • Returning Visitors

    If you are a returning visitor who never received your confirmation email, then odds are your email provider is blockinig emails from our server. The only thing that can be done to get around this is you will have to try creating another forum account using an email address from another domain.

    If you are a returning visitor to the forum and can't log in using your old forum name and password but used to be able to then chances are your account is deleted. Purges of the databases are done regularly. You will have to create a new forum account and you should be all set.

Here a Volt, there a volt, everywhere a volt volt

  • Thread starter Thread starter barnbiketom
  • Start date Start date
B

barnbiketom

Guest
I think it's easy for us old guys to visualize why a bike won't start or run, but for the new people I'll give a nice example.

81 GS650L cranks but no start....every once in a while it starts and runs great.

I noticed something that I've seen on a few other GSs in that whenever it DOES START, it is always when I am LETTING OFF the starter button..
as if it catches just at the last moment. I figured a low voltage to the ignition of course like most of these bikes have..
I did a voltage drop at the coil +wire and found THREE volts gone missing!!
Where did the volts go?

To do a voltage Drop Test, you simply place the two leads of a voltmeter on both leads of a suspect component (or circuit) while powered up.

This test, I was testing the power to coil circuit. One test lead on the + BATTERY, the other on the coil + power wire.
In a COMPLETELY GOOD CIRCUIT, you would see very little voltage, as it is actually the SAME WIRE OK??
But in my case, I see 3 volts and that is a NO_NO.

I did the drop test on various things , like the ignition switch in and out and I lost .4 volts. I cleaned the switch and ended up with .2.. "OK" i guess.

The actual wiring to and from the switches was good, some connectors just simply unplugging and plugging in improved it by a .1v drop.
The most drop was in the fuse box and when initally testing it it was not nearly as bad..???
After not finding my elusive other 1.5 volt drop, I tested it again. and found THIS FUSE. It fell apart in my fingers.
13129369533_0122ea38e8_z.jpg

I plan on replacing the fuse box with ATC spade fuses , doing a coil relay mod, and rect/reg loop elimination.

I bet it starts better!!
 
I think it's easy for us old guys to visualize why a bike won't start or run, but for the new people I'll give a nice example.

81 GS650L cranks but no start....every once in a while it starts and runs great.

I noticed something that I've seen on a few other GSs in that whenever it DOES START, it is always when I am LETTING OFF the starter button..
as if it catches just at the last moment. I figured a low voltage to the ignition of course like most of these bikes have..
I did a voltage drop at the coil +wire and found THREE volts gone missing!!
Where did the volts go?

To do a voltage Drop Test, you simply place the two leads of a voltmeter on both leads of a suspect component (or circuit) while powered up.

This test, I was testing the power to coil circuit. One test lead on the + BATTERY, the other on the coil + power wire.
In a COMPLETELY GOOD CIRCUIT, you would see very little voltage, as it is actually the SAME WIRE OK??
But in my case, I see 3 volts and that is a NO_NO.

I did the drop test on various things , like the ignition switch in and out and I lost .4 volts. I cleaned the switch and ended up with .2.. "OK" i guess.

The actual wiring to and from the switches was good, some connectors just simply unplugging and plugging in improved it by a .1v drop.
The most drop was in the fuse box and when initally testing it it was not nearly as bad..???
After not finding my elusive other 1.5 volt drop, I tested it again. and found THIS FUSE. It fell apart in my fingers.
13129369533_0122ea38e8_z.jpg

I plan on replacing the fuse box with ATC spade fuses , doing a coil relay mod, and rect/reg loop elimination.

I bet it starts better!!

Congratulations the first step to a solution is being aware of the problem. :) The Solid State Power Box is designed to address the issues you are documenting in a comprehensive way using modern automotive grade solid state electronics. In fact it eliminates the fuses by employing electronics that constantly detect current. If the current exceeds the 10 amp level of the fuse, it shuts it off until the short goes away. It then just goes back to providing the in spec current.There is much more........

Read about the SSPB in the link in my signature.
 
Last edited:

I noticed something that I've seen on a few other GSs in that whenever it DOES START, it is always when I am LETTING OFF the starter button..
!

Yes, voltage drop if you want to call it that. Load is what Id call it. Your starter motor is loading down your battery which robs voltage to your coils. Let off the button an you get more power to the coils. I don't think a new fuse will do anything for you. New battery ? Probably....
 
Yes, voltage drop if you want to call it that. Load is what Id call it. Your starter motor is loading down your battery which robs voltage to your coils. Let off the button an you get more power to the coils. I don't think a new fuse will do anything for you. New battery ? Probably....

Dave he was measuring voltage drop across the wire/connections not how much the battery was dropping.

This test, I was testing the power to coil circuit. One test lead on the + BATTERY, the other on the coil + power wire.
In a COMPLETELY GOOD CIRCUIT, you would see very little voltage, as it is actually the SAME WIRE OK??
But in my case, I see 3 volts and that is a NO_NO.
 
Well I use the K.I.S.S. method lol.. I'd bought 3 nice 5 fuse ATC blocks and have one left.. I may use the leftover loop wires for the new coil + wire but I also have some ANCOR marine 14AWG stranded in RED and a ton of take-out relays from the wrecking yard..and I really don't care how it looks under the side cover or seat.., just that my coils, ignitor, and R/R have proper power and ground. I always use a continuous run to ground them all anyway..Not that the SSPB isn't a great achievement.but would rather go old school.. fix it when it breaks!
I used to always "upgrade" to electronic ignitions and had a knight kit one on my 68 barracuda lol... now that you know i'm OLD..
anyway... I nowadays like the STOCK stuff.
 
Last edited:
Well I use the K.I.S.S. method lol.. I'd bought 3 nice 5 fuse ATC blocks and have one left.. I may use the leftover loop wires for the new coil + wire but I also have some ANCOR marine 14AWG stranded in RED and a ton of take-out relays from the wrecking yard..and I really don't care how it looks under the side cover or seat.., just that my coils, ignitor, and R/R have proper power and ground. I always use a continuous run to ground them all anyway..Not that the SSPB isn't a great achievement.but would rather go old school.. fix it when it breaks!
I used to always "upgrade" to electronic ignitions and had a knight kit one on my 68 barracuda lol... now that you know i'm OLD..
anyway... I nowadays like the STOCK stuff.

The other place to look is beyond the fuse clips. Those older fuse boxes have pigtails with a connector at the end. So inside of the fuse box there are crimps to attach the wire to the clip. I would take the back off, put some naval jelly inside and clean it all out then solder the crimps and spray the fuse contacts with DeOxit.

picture.php
 
The other place to look is beyond the fuse clips. Those older fuse boxes have pigtails with a connector at the end. So inside of the fuse box there are crimps to attach the wire to the clip. I would take the back off, put some naval jelly inside and clean it all out then solder the crimps and spray the fuse contacts with DeOxit.

picture.php
I'm replacing it . similar to this:http://www.ebay.com/itm/ATC-Fuse-Bl...367?pt=LH_DefaultDomain_0&hash=item3cd8022a7f
And on my ignition switch, after polishing with a leather belt on the contacts, I SOLDERED all the crimps on the back:)
 
I'm replacing it . similar to this:http://www.ebay.com/itm/ATC-Fuse-Bl...367?pt=LH_DefaultDomain_0&hash=item3cd8022a7f
And on my ignition switch, after polishing with a leather belt on the contacts, I SOLDERED all the crimps on the back:)

If you don't want to spend the money on a SSPB, I would at least spring for one of the options that have an internal relay . The PC-8 ( Eastern Beaver ) is popular and I think there are posts showing how to install it.

I would buy a stock fuse and make sure it is cleaned and soldered before using a fuse box of that type.
 
Back
Top