17 miles per gallon...

[toogun]

Went through my first tank of gas of the season, mile mileage has gone from aprrox. 35 mpg to 17 mpg!!!
Quick rundown of what was done prior to getting back on the road.

1. Changed oil to 10w-40 Synthetic from Semi Synthetic.
2. Installed new plugs NGK DPR6EA9, same as what the old plugs were.
3. Modified my V&H Bagger baffles by extending the baffle and welding in 2 baffles halfway through the extension. and wrapping them with sheet metal instead of the glass packing.
4. Cleaned and oiled the K&N air filter with K&N cleaner and oil.
5. Marbelized the reed valve.

The baffle mod consisted of a 9" pipe welded onto the baffle giving an overall length of 19 1/2". I had originally cut 4 slots for baffle plates but only ended up using 2. Thinking that the OAL might be a problem (too much back pressure) tonight I cut off the extra 2 slots reducing the OAL to 16". I'll have to see how this affects the sound, performance etc.
The other thing is the amount of carbon on the end plate of the baffle was extreme especially for only 60 miles.
I'm also wondering about the sheet metal wrap, I wrapped the metal tight to the original baffle with no space in between. Should there be any air space? If so how much.
Pics attached;

Pic 1. Shows the carbon from the inside flange versus what it looked like before the above mentioned mods.

Pic 2. Shows the baffle plates in the extension.

Pic 3. Shows the sheet metal wrap on the original baffle.

Any comments, suggestions greatly appreciated.