Okay so this winter I installed a stage 1 air cleaner and true duals, re-jetted the carb to a 180 jet, I'm running Screaming eagle plugs with 10mm wires which I had on last year at the end of the season. My mileage went down to 36 mpg from 40 to 45. I just installed Screaming eagle street cannon mufflers and added baffles to drop the sound levels to legal levels. Sounds great and plugs look good. I'm thinking of going back to stock air cleaner? anyone have any ideas.

 

Baffles will help, true duals aren't as efficient in our bikes as the stock 2 into 1, but it's better with baffles vs open pipes. See if that gives you back some mileage.

Air cleaner won't make much difference at all based on my research and comparative dyno sheets I found.

 

You may need to make a small adjustment to your carburetor since you made a change to the exhaust.

The screamin eagle air cleaner kit (not just a filter dropped into the stock air box) flows a lot more air than stock. I initially had a drop in filter and switched to the full kit and it really let it breathe a lot more and enhanced the other stuff I did to the engine.

The thing about mpg on these bikes is that once you unleash more power, you will unconsciously twist the throttle harder and faster which of course burns more fuel.

I was curious what cam are you running?

 

Stock cam, just had that and the oil pump and push rods done. The air cleaner is an Arlen Ness Stage 1

 

An evo comes jetted fine with stock main jet,it's usually the low speed jet and idle adjustment that must be changed.

 

Exactly what bike and what carb are we talking about here?

 

Bike is a 93 EVO Tour Glide, stock carb. main jet is stock and idle is a 180

 

A 180 jet is the main jet, not the idle jet, which is around a 45. Has the blank over the slow speed adjuster screw been removed, so you can adjust it?

 

Well that makes sense now, so I have the jets reversed. The 45 that it should be is actually a 42 that is in there now. Yes I installed an easy adjustment screw so I can fine tune the carb and have it not just a hair above popping upon acceleration and drop off.