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Discussion Starter · #1 ·
Just picked a 73 500F survivor from a buddy. Original condition with 5700 miles. Won't get into back story we worked on this bike a few years back got it running with new tune-up parts, started right away. Fuel tank was dirty and carbs needed rebuilding which have now been done tank cleaned and coated. New battery. Went to fire it now no spark. Nothing has been changed since we touched it before. Bike always stored inside. Reluctant to start throwing parts at it. Clymer manual not much help with troubleshooting. Appreciate any experience and suggestions on next steps.
 

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Start by checking all connections especially the coil a crank sensor. Then you will have to test the coil and crank sensor. Clymer should show you how, they are good manuals.
 

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2017 Aprilia Tuono V4 1100 Factory
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You won't find a ton of experience with the 4-cylinder "first gen" CB500F here.

However, a motorcycle is a motorcycle and the wiring on older bikes is often quite a bit simpler than on later machines.

Your ignition system is going to look something like this:



Some ideas:
  • check to see if you're getting Vbat (12V) at the coils with the ignition on; if not, you may have a blown fuse, ignition switch, run/stop switch issue etc
  • (ign off) inspect the breaker points; check for pitting or corrosion that might cause a bad connection. Use some fine emery paper of a tiny fine file to smooth and clean the contacts
  • (ign off) check the point gap for both sets
  • (ign off) disconnect the condensers, turn the ignition on and see if spark returns; if it does, the condenser(s) are bad. You can verify with an ohmmeter between the condenser lead and the body (low resistance is bad). Don't run without the condensers for more than a few seconds or the points will be ruined in short order by arcing.
 

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Be sure to check and clean all grounding connections - esp. with the coils, etc. Rust, and corrosion will often cause problems like that

I also have had problems with plugs not firing and new plugs helped.
 

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Discussion Starter · #7 ·
So 1973 - Does it have points??
Has points which were replaced when we first worked on it. Also new condensers and look in good shape know that does not mean they are good. Ordered new parts inexpensive enough.
 

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Discussion Starter · #8 ·
Be sure to check and clean all grounding connections - esp. with the coils, etc. Rust, and corrosion will often cause problems like that

I also have had problems with plugs not firing and new plugs helped.
Did look over connections will do so again. Has points which were replaced when we first worked on it. No spark at points. Also new condensers and look in good shape know that does not mean they are good. Ordered new parts including inexpensive enough.
 

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Do you know if there's 12V power available at the ignition coils?
 
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