On my r90/6 I use an electronic vacuum gauge to set the throttle stops and the cable synchronisation. I have fitted vacuum ports to the inlets, can I use the same method as with my BMW given that the crank rotation is not even on the ducati engine. Everything is apart at the moment so I can only talk theory charles
The SS can be really picky about mixture screw position so dont think 1.5 turns or 2 turns, think 1.5 or 1.6 turns. Getting the pump volume set correct will also pay dividends.
@Mullinsm I really enjoyed this video, thanks much for sharing it here! PS: It definitely looks like Australia (or NZ?) but he sounds very American to me. PPS: Special mention to the “siliconed nipples” moment…
Interesting video, withe most post points ignitions it’s not considered to be good for the long life of the ignition system to take off plug caps without grounding the lead. I use a Grok Harmonizer which looks easier to use. Set throttle cable synch at 2000 rpm, incredibly sensitive on the throttle cable adjusters
He is isolating each cylinder so adjusting them one by one. If he grounded the spark plug he removed then that would be ok
What energy is there coming from the spark plug once the cap is removed? Isn’t all the energy (very high voltage) coming into the plug cap from the coil? Honest question. I would like to use the same method (isolating each cylinder) without risking to damage the coils, and so far I understood something needs to be grounded when you remove the spark plug cap.
Isolating the cylinders seems like way too much faff to me for all you are essentially doing is adjusting the idle mixture and synchronizing the carbs. And I suspect the latter can't be done when running on one cylinder.
So, having fitted a brand new set of carbs, I find that they clearly were't the issue. I now have nice, shiney carbs and still no tick-over. I've fitted the carbs without altering any jetting from standard and I have to assume the float height will be OK on new carbs. There is definitely no air leaks on the inlet side - the gaskets are new and fully sealed. I've set the mixture screws at 1.5 turns out and synchronised the slides using a vacuum gauge at 3000rpm by lifting the slides on the top cable adjuster. As soon as I try to lower the slides to obtain a tick-over below 2000rpm, the engine starts to back-fire and blow-back through the carbs and then dies. Any suggestions?
Perhaps the ignition is misbehaving - the standard Bosch should have a 6 degree advance at idle (900 rpm), a sudden jump to 16 degrees advance at 1800 rpm and another to 28 degrees at 2800 rpm before progressively advancing from here until 4000 rpm. Or perhaps as per my previously mentioned wild idea the routing of the fuel line over the carb(s) is somehow causing starvation issues.
Both fuel pipes are full and no bubbles. The ticklers flood the carbs ok so I don’t think it’s that. Im going to check the ignition and valve timing next. It could be the advance I suppose……
Perhaps it is just for my own curiosity but re-routing the lines is cheaper than a set of carbs and less work than checking the valve & ignition timing....
Un Unlikely as it was working and the bike runs well enough once you open it up. I’m thinking the advance could well be the problem….
