Looks like you've attached this problem logically. I would adjust the fuel/air mixture screw in to 2 to 2.5 turns. Your more than likely on the right track with electrical.Hey all!
First bike, first post.
Got a 2006 Honda Shadow VT750DC (dual carb), 5700 miles. I cant get the bike to run.
Symptoms: It will start on full choke but then die out after 30 seconds or so, if I set it to ½ choke after 30 seconds it will run an additional 10-15 seconds then die. It will not start or idle without the choke.
Throttle causes a lag and sputter during the first quarter throttle. Once its opened all the way up it will run at max RPM but when I throttle back to close to quarter throttle it will die.
Based on what Iv researched to far most folks point to an issue with the pilot jets, that its not getting enough fuel during idle as well as lower throttle levels.
Here’s what Iv done so far:
My best guess is that after all this I have to start examining the electrical system. Part of me says its probably something dumb that I am overlooking as a naab but you don’t know what you don’t know.
- Both carbs have been disassembled, soaked and scrubbed with carb cleaner. Iv soaked and run fine wire thru all 4 jets. You can clearly see thru all 4 jets; pilot and main, on both carbs.
- Floats work as expected, no discolorations or deformations.
- Ran compressed air thru the main airways of the main carb body, nothing is blocking the pilot or main jet airways that I can tell.
- Carb boots are in good shape, still soft and malleable, forms a good seal when clams are screwed down.
- Iv checked for air leaks throughout the main engine area, Iv sprayed starter fluid on all the boots and gaskets. No RPM increase anywhere.
- Fuel/Air mixture screw has been cleaned, reset, and re-zeroed, currently at 3 turns out.
- Air intake and exhaust are both factory and in good shape, newer air filter.
- Battery is newer and seems to be working fine based on a meter test.
- Fuel pump seems to be working fine initially, pump fills the fuel system and carb with fuel right away after reinstalling the carb on the motorcycle and the bike turns over and starts with choke at 100%.
- No blocked or constricted airflow anywhere that I can tell
- All tubing around the motor and carbs are in good shape, no cracking or splitting middle of the tube or at the ends.
- Spark test has been done, all 4 produce a good spark.
- Plugs are in good shape; they were replaced fairly recently.
- Black soot on the outer ring and white soot on the inner ceramic rod/pin, seems to have a decent fuel mix but Im no expert (pics included for reference).
Any suggestions would be appreciated.