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Still carb troubles

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billdn:
Back in February I posted saying I think I'd sorted my troubles with carbs not shutting down . In April I went for a Boyer electronic ignition complete with micro coils and I still have the same problem with the carbs !
There's quite a long time between posts because my wife was very ill with lung cancer and sadly passed on 30th June , so shed time was the last thing on my mind!
However one of her last wishes was "Get that bl##dy bike sorted!"  So I'm now back in the mood to try and sort it.

From the top :-
Boyer fitted and bike starts/runs. Using a timing light its correct.
Tappets adjusted.
Have to fiddle with idle adjuster to set at 1200rpm .
Idle mixture screw set at 2 turns out.
Plugs very sooty
Open throttle and revs soar and doesn't drop back to 1200rpm when released. Have to fiddle with idle adjuster to bring back down.
Sprayed carb manifold connectors to barrels with Carb cleaner and no effect , so not drawing in air, better not they're new - good
Remove carb tops and sprayed carb cleaner in but slides don't appear to be sticking either.
I've noticed that if you press the top of brass hexagonal nut on the carbs this will reduce the revs but too hard and it stalls FWIW.
Prior all carbs stripped, ultrasonic cleaned, carb cleaner on jets with jet brushes etc etc retaining original brass and new seals from NJ.
Bench synced at least twice.
Standard air box and new air filter

I've no idea what to do next! I have an old lawn mower, never serviced, starts first time every spring,  think I'll put engine from that in instead.

To me it's pretty obviously  carb related, (I think  ::)) as there is good spark and timing is ok. Not got to the stage with setting Boyer to full advance  yet which requires 4500rpm as revs all over the place.
Cheers peeps! 8)

Nurse Julie:
So very sorry to hear of your loss Bill 😢😢😢
Also so sorry to hear you're still battling the carb gremlins 😁😁😁😁

Oddjob:
Very sorry to hear about the wife.

You could try this as to me it sounds as though the throttle lifters are set too high, especially if the carbs have been apart.

Get the adjuster screws, the ones with the little 8mm headed nuts on and the flat bladed screwdriver slot. Screw them all down as far as they can go. You may now struggle to get the bike to tickover and starting will involve a little jiggling with the throttle. Once you get it started adjust the main tickover screw to see if it will idle. If so, now vac the carbs to equalise them.

See if that works.

Before you do that post a pic of the adjusters so we can see how high they are now.

Matt_Harrington:
Bill, sorry to hear about your wife......

As Ken says, the adjusting of the lifters can have a remarkable affect on the tickover and settling back to idle.

royhall:
Sorry for your loss Bill.

That sounds to me like the quadrant is not positioned correctly when it was reassembled. Got the tee shirt for that one, took me ages to find it but the symptoms were as described above. Repositioned things correctly and it was spot on. Unfortunately the old memory won't allow me to remember how I fixed it but someone will know.

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