So. Over the winter I installed some Vance & Hines 'Hi-Output' mufflers, and finally did the carb work to get performance (off the line mostly) correct.


I have the stock Harley CV carb that I went through (smoothed/drilled the slide, shimmed the needle & cleaned)...after test riding, I ended-up sticking with a #50 primary jet (factory was almost impossible to read, it was either a 42 or 44) and a #215 main (stock was a 185).

The bike runs great now, good 'off the line' and 'roll-on' acceleration...my issue is fuel mileage. NOT because I am really worried about MPG, but just because it seems REALLY different than prior to the carb work.
- I say this because today, and the last time I was able to get the bike out, it died while riding (restarted easily & immediately when I hit the reserve) about 40-miles before I would have switched to reserve before I did the carb work.

Would the difference in those jet values make a (roughly) 25% difference in fuel economy? If so, that's fine...just winding if it's normal.


Other motor work:

K&N air filter
Headwork (porting, polishing)
.203 cams
95" pistons
Exhaust

 

the last fine tuning I did was on my 80" evo.
stock motor, hi flow intake and tuneable supertrapp exhaust, stock headers with o2 bung. Crane hi4e ingition with multi spark, timing advanced about 3º

by doing "loops" on a 67 mile piece of hwy, i was able to tune that bike to 45 MPG at 65 MPH with 10% ethanol gas.

as I recall drilled and chamfered slide, sportster needle ( N65) with a .050 washer.
42 slow speed jet, 170 high speed jet.

I had started out with larger high speed jets, but kept finding that I was too rich at cruising speed as determined by the o2 sensor and the voltmeter taped to my handlebars.

that carb tuning gave me good clean power and good mpg, passing was sluggish in 5th, so a drop down to 4th was needed.

after that tuning session i did a 10,000 mile trip and was oh so thankful for the mpg in the boonies

nightrider.com has some good cv tuning tips in the biketech section

Mike