As I mentioned in another post, I have just put about 1000 miles on a new
Boston Bob 2.1.  The old engine got 17-21 mpg, generally less than 20, and I
was hoping the new one would be a bit better.

Unfortunately, I'm looking at 15-16 on the highway.

The posts on the pressure regulator have been interesting, but here's the
situation, and our current plan to bring this up a bit.

The cat broke during the course of the engine swap, and plugged up the
muffler, so we gutted it and I'm waiting to get a new one.

My mechanic doesn't have a working CO tester, so he left the AFM settings
alone.

I have a digitool.  The Temp I and Temp II sensors look about the same as
they did on the old engine, identical when the engine is cold, with the Temp
II getting down to .09-.11 when the engine is warm.

Throttle switches seem to turn off and on like they should.

The O2 sensor starts at about .35, and on warming up bounces from about .8
to 0 or below.

The AFM readings move smoothly along the scale.

Fuel pressure regulator has 34 psi with the engine idling and the vacuum
line connected, and 38 with it disconnected.  Bentley (24.55) says 29
connected, 36 disconnected, so that's a bit high.

I believe I have the longer duration cam, as described by Robert Lilley.

To tackle the low mileage, Bob Donalds suggests replacing the Temp II just
because it's old, and checking the resistance on the Temp I.  Then get to a
mechanic with a CO meter and adjust the CO screw on the air flow meter to
see if we can get to spec.

If not, consider replacing the pressure regulator and re-testing.

Any other suggestions?

- Mike Finkbiner (Who is not looking forward to higher gas prices!)
'87 Westy
Moscow, Idaho
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