03 ultra still runs rough

[chas]

I just did a 100" big bore this winter, started it up and took first ride. Before I tore engine apart the bike was running rough last fall. Thinking it was the ets i replaced it with new and bike runs rough and back fires like crazy! I will check codes on pv. Could it be another sensor? TIA

[kd]

You don't say but with an ETS it sounds as though you have a fuel injected engine. Check the fastener on the grounded wire on the frame backbone up under the rear of the fuel tank. Also, if you installed a 100" kit to your 88", including changing cams and other parts and didn't have it tuned I wouldn't expect it to run any better. In fact, running it like that you may be undoing all your time and money by causing damage to the engine.

[rigidthumper]

What's the fuel pressure? When was the last time you replaced the fuel filter? Have the wires for the injector plugs been tested for internal breaks? Which base map is in your PV?

[tdrglide]

03 touring was notorious for broken wire inside insulation at front fuel injector
Wiggle test at injector plug may give an indication