86 VFR750 - Changed Starter Clutch Now Bike Just Backfires and Won't Run

[Captain 80s]

Pretty sure the pickups are the magnetic component.  They usually have a little "fuzz" that I wipe off when I'm in there.  You can see that the "triggers" are just a pressed ridge out of the steel in the outer shell.

[GreginDenver]

As I am naturally unafraid of re-wiring the electrical wiring in cars and motorcycles, the question I would be asking myself is...

 

If the '86 trigger wheel is discontinued and only the '87 (and onward) trigger wheel is available, how hard would it be to fix the issue by working from the other end of the system by substituting/retrofitting an '87 ignition control box on an '86 VFR?

 

The question would be: How much of the bike's wiring harness was changed from the '86 model to the '87 model?  If the only change was the obvious switch from analog trigger wheel to digital trigger wheel for ignition control then swapping in both an '87 trigger wheel and the matching '87 ignition control box would be possible.  

 

I can tell you from experience that these old-school ignition control boxes (on 1980s carbureted bikes) often only have 6 or so (maybe up to 10) inputs (wires).  It wouldn't be too hard to track down all of the inputs to see if you could make the swap (you might have to "re-pin" the connector to bring in all the correct inputs to the correct placement on the ignition control box).

[Captain 80s]

The 86 engine has a cam position sensor, but it might not need to be plugged in after a change over.  The tach might need some problem solving too.  I still think there is a mechanical solution here after some destructive investigation.  Cheaper than buying 87 Control units and possibly wire harnesses and gauges.

 

But I really like this approach.  I don't own any 87 models or parts to experiment with on my last 86 VFR build coming up.

[squirrelman]

i have an '86 starter clutch in fine condition for sale but it's not cheap.

 

[trevorb]

i had this issue on my '86.......i fixed it by utilising the method mentioned, separating the inner and outer parts and fitting a new inner from '87 and tig welding the 2 parts in 3 equal places around the perimeter. That was 3 years ago, no probs so far, for me this is the only solution for '86 bikes with this issue.The metals are dissimilar but tig ok.

The mileage was approx 66k miles, i bought a used engine for £100 and same mileage but the starter clutch was already cracked at the common places. its a weak spot at the base of the hole where the support springs/plungers fit.

Sorry no photos, but i hope you can work out the solution by following the thread .