'86 XJ700 - Ignition issue (no spark)

Hi all!

New season, new issues with my 1986 XJ700.

Last season went in the end without having the need to clean the carbs. I used the bike quite a lot.
However, in October the bike needed to be parked in the garage since one of the front shock absorbers started leaking hydrolic oil , so I decided to perform a thorough front fork rebuild.
I took my time and succeeded, but the bike has not been in use for those few months.

Current issue: The bike does not start again. This time it seems to an issue with ignition system. There is no spark on either of the 4 cables when tested with and without spark plugs.

The electrical starting system seems to work as intended - I can hear it operating and see the rotations on the tachometer.

Question: where do I start with identifying the problem? I watched a bunch of videos and based on the scheme I can perform all checks APART FROM checking the first step: checking entire ignition connection. Please, consider that even though since owning the bike my understanding of bike mechanics has increased drastically, the electric circuit is still a bit opaque to me and it has been a while since I played around with those during my bachelors studies.

Where do I start? What do I do to find the faulty parts? It might be simply a disconnected plug BUT how do I find it? If it is the master fuse, how do I find it too?

Any help would be greatly appreciated.

Additional details:
- The bike worked quite well until October 2023
- Since then it was parked in an underground garage with stable temperature
- In the meantime, due to my stupidity when working on the front fork, it fell on the side once. No damage resulted from the fall, just a bit of spilled gasoline. But the current problem might be related.
- I attempted to start the bike a few times with a fully charged battery and sufficient petrol, always fails (as described, no spark, but the electrics starter system works)
- I tested the ignition system like that:


Overall
I want to perform a full ignition system check according to the scheme below, but I don’t know how to start.

Thanks in advance for all of the help! You guys have been incredibly helpful so far and made me learn an immense amount of skills.

 

Welcome to XJ Bikes. Did you check the voltage of the fully charged battery? How old is the battery? If battery voltage falls below 10 volts when you are pressing the starter button you won't get a spark. Put a multimeter on the battery terminals set to 20V DC and press the starter button. The cranking voltage should not drop below 10 volts.

 

Thanks for the reply. I should have specified it in the previous message.

It is not a battery issue - the battery is 2 years old, charged to full with a charger before each ignition attempt, multimeter indicates approximately 13.4 V at full charge

 

SQLGuy did a write up on checking the ignition system. Here it is.

https://xjbikes.com/forums/threads/how-to-ignition-troubleshooting.21932/

 

That is brilliant thanks!

 

Update: After performing the listed checks with a friend, it turned out that the battery was not capable anymore of igniting the motorcycle (even if charged to full), but also the primary coil required an exchange

 

Interesting....

I found my XJ700 to be very sensitive to battery condition too - there must be something different (more power required for something) that seems to make them require a *really* good battery. In contrast, the XJ650/750 seems to be very forgiving even with a weak battery.

Just my observation.... Might be complete B.S.

 

Hi Dan. Sounds quite reasonable - the old battery was still only 3 years old and the voltage drop measured by the multimeter was not that bad.