B6 Fuel Mileage

[Big_Jim59]

I have been riding my B6 and I really like it except for the fact that I am getting 28/29 miles per gallon of gas.  I am running drilled out adjustment screws turned out three times, a stock air box, a stock air filter, a stock muffler from a 2000 B12 and 95 main jets. It runs good but seems a little fat on the low end. I can start it with no choke. (this my not be a big deal because it has not been what you call "cold" here. The spark plugs look gray. It is turning about 6 grand at 70 miles an hour.

Is this normal gas mileage?

[bullet5]

Why have you drilled out the adjustment/pilot screws? This will no doubt be causing the rich running at idle.

Anywhoo, a B6 should average about 45 mpg (british) through stop/start riding, and about 50-55 on a long highway run.

Rev wise with standard gearing, I get bang on 5k revs for 60mph, and this is the norm.

Hope this helps somewhat,
Bullet5.

[Big_Jim59]

I don't know about the UK but here in the states the bikes were delivered with the pilot screws capped and non-adjustable. By "drilling out" I meant that the caps had been drilled and removed and the pilot screws turned out to richin the idle mixture.  I don't think that should cause such bad fuel mileage. The funny thing is, other than the gas mileage and smelling a bit rich, the bike runs really well.

[Red01]

That's sucky mileage, even to US gallons.  The B6 should get better mileage than a B12, and a stock B12 should be getting 40 or more miles to a US gallon.
I'm not real up on B6 jetting numbers, but there are some threads in here that discuss B6 jetting.

[rider123]

Air filter dirty? Maybe go buy a new one and see if that helps you out. For fun you could also order the K&N panel filter but you should be rejetting for it. If you pop in a new stock filter and it's all hunky dory, then great problem solved. If the milage is still sucky after a new stock filter and it's running rich try popping in the K&N and see what happens. I just replaced my filter after only half the season and it was dirty as hell, sometimes you need to change it early.