86 VFR700 died during ride... now no spark.

Hi all,

So I took my recently aquired VFR700 for a nice sunday ride a few weekends ago, ran perfectly for an hour or so... stopped at the gas station and filled up, started straight up again, so start off again... 5 minutes later it starts to splutter and cough, as though its starving for fuel (?), then it dies on the side of the road. Crank it, crank it, no go.. even tried push starting (this bike is lot heavier than my 250!).

Got it home and started checking things, fuel pump ok, getting fuel. But checked tonight and no spark. this is from taking coil cable out and hooking spark plug back in and cranking with recharged battery. Checked fuses, all ok.

What could it be? I checked kill switch, when key is in on position and i toggle killswitch I hear a click from near the battery. Does this mean its working okay? Next thing I looked for was CDI... and ... I can't find it. Oh dear.

Any help much appreciated.

 

Lack of spark on these can get hard to sort out, can be a broken wire somewhere, pulse coils , CDI unit

 

I've got a parts bike but to an 88, i understand the cdi is different?

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Yep. There were a couple '86 700/750 CDI units on the US eBay a few days ago. Reasonably priced too.

 

CDI on that bike is located just in front of and below the tail light. you may need to remove the sub-subframe that holds the seat lock latch plate to access the box.

I suggest checking resistances of the pulse generators when engine is hot. Lost spark on all 4 plugs or only 2 ??

 

All 4 plugs have no spark... so can't get bike hot. Wanted to try different CDI but wrong year...

Will get cdi out tonight, and see if i can test voltage to the cdi at least. What would be clicking when I switch on and off?

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The clicking is the fuel pump (most likely.) If there's no spark anywhere, you're probably right about the CDI. I think these bikes were pretty popular down under. Maybe you could source a part from there? A skilled tech could also repair them in some cases. Many times the capacitors begin to leak and the connections at the harness port get too hot and fail.