Electrical / Timing issue? Trying to ride to BF10

Surfrat28

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Hey everyone!

Bike: 1979 Yamaha xs650SG bored out to 707
Ignition system: Boyer ignition

I just got a new battery and it was running the other day but by the end of the day it would not turn over. The lights don't look dim but I know that its not getting enough power to get it started. I have attached the wire diagram that I had gotten help with from the forum. Could it not be charging when it is running and just drains my batter? I have even charged the battery and now it will not go. Any thoughts?? Please ignore the kick start only it is only.


yamaha xs wire diagram.jpg
 
what does a volt meter says about battery condition, what battery you got? Sounds like it wasn't charging.
"ignore the kick start only it is only. "????? I'm not fluent in gibberish. (wife would differ)
 
what does a volt meter says about battery condition, what battery you got? Sounds like it wasn't charging.
"ignore the kick start only it is only. "????? I'm not fluent in gibberish. (wife would differ)


The battery is at 12.35 then once I press the button for 2 seconds it goes down to 11.45. This is a brand new battery and I had road on it for about 10 miles and then when I got back home I tried to go out again and it would turn over. The main wire to the positive battery seemed to be getting pretty hot. and now the solenoid does a click every time a push the button now.
 
You need to perform the simple charging test. Pretty much all of these should have this test done when you get one then periodically afterwards. Hook a voltmeter to the battery and rev the bike up. At idle you should be seeing around 12 volts, revved a bit over 14. If you get no increase in voltage when you rev it, you're not charging.
 
brand new junk batteries happen, not say'n that's it, but don't rule it out. Leave key off short solenoid terminals with big screwdriver what happens?
 
brand new junk batteries happen, not say'n that's it, but don't rule it out. Leave key off short solenoid terminals with big screwdriver what happens?


Sparks but doesn't want it to turn over. You can hear the compression when it tries to turn over (if that makes sense)
 
You need to perform the simple charging test. Pretty much all of these should have this test done when you get one then periodically afterwards. Hook a voltmeter to the battery and rev the bike up. At idle you should be seeing around 12 volts, revved a bit over 14. If you get no increase in voltage when you rev it, you're not charging.


need to get the bike started first, but will try when I get another batter sometime today and hopefully that will work
 
These are usually easier to kick start than electric start if the battery is low.

As far as that diagram goes, I don't see a regulator pictured anywhere, just a rectifier. Without that, I don't think it will charge. The regulator feeds regulated power to one of the brushes (outer one), that energizes the rotor, and that makes the alternator produce an output. That output is AC but it gets fed through the rectifier and that turns it into DC that the bike can use.
 
was guessing it's really a PMA alternator?

Thank you for the help! I really tried to push it to get to that show on this build.

Stock set up on everything except the Boyer system. Didn't make it to BF10 on that bike couldn't even get to turn over. I am guessing its either a timing issue or not getting gas somehow. It just wont turn over, I have spark, I have gas in it.
 
Just what do you mean by "turn over"? The starter won't crank or spin the motor, or it spins but just won't start? That would be 2 different issues, maybe not even related.
 
Just what do you mean by "turn over"? The starter won't crank or spin the motor, or it spins but just won't start? That would be 2 different issues, maybe not even related.

Wont start. Only way we got it to get even close was to bump starting it but wants to die in seconds. Im thinking it might be a fuel issue now. I have spark.
 
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