Honda Shadow, spits and sputters

How-To: 4° Advance Timing and Clutch Spring Upgrade - Honda Shadow ...

www.hondashadow.net > ... > Technical Discussion

Dec 26, 2012 - Tweaking your timing will not directly cause your engine to gain more power, but ... gas mileage, make the motor burn cleaner and give you a better throttle response. ... And this is being done to a 2003 Honda Shadow ACE VT750. ... Permatex Ultra Black gasket maker (or new gasket pre 2002 I believe)

Shadow vt750 oil ' Cruiser Community

cruiser.mototribe.com/discuss/shadow-vt750-oil

Hi, I have a shadow vt750 and I buy it with 20w-50 synthetic oil and I have doubt .... would probably not provide adequate lubrication for hot weather, high speed driving. .... is is ahardtail dropped 4 inches 03 chain drive ONLY Honda 750 V twin. ... out cylinder jugs"the rest of the engine,trans are still polished chrome,custom ...

How did you check the petcock? sure its not that.Yeah swap coil packs then ask again.

Disconnect battery cable, reconnect, and then try again.

coils, when coils get hot they will quit working.

Hi there
I once had a wee car,whenever it got too much petrol inside itself it refused to go anywhere and had to rest for some time and you had to be very careful with the choke and the petrol so it did not swallow too much of it and need another rest.
kolbrun

fouled plug, bad plug wire, junk gas, clogged fuel filter

I'm not personally intimate with the Shadow, but on most motorcycles this is generally indicative of charging system issues. You may have lost a phase in either the stator and/or regulator.
Measure the voltage across the battery with engine running and ensure you have better than 13.5V.
If not that will confirm that your charging system needs to be further investigated.

Sounds like a grounding problem. I know not easy to fix. To start with, I suggest running another ground wire (just a jumper wire with alligator clips on each end) from the instruments to the frame and see if the problem goes away then if fixes make the repair perminent. Best wishes.

Since it ran fine before you "fixed" it, go back over the things you changed. Put the old spark plugs back in it. Double check all spark plug wires and ignition connections. Put the bike in a dark area and run it at night, can you see any arcing anywhere?