Inspired by Micky and the other guys trip to the Dyno I got to thinking about the setup on my PD.
Yesterday's weather was perfect for a spot of engine tuning so I rigged up my PD with my air fuel ratio meter. There's a stretch of motorway near me that has a long steady climb that is perfect for load testing.
After a few runs and a couple jet changes and needle adjustments I ended up with what appears to be the perfect set up. This is a full throttle run in fifth gear from around 60 Mph. The spike at 12 seconds is me rolling the throttle off.
It looks nigh on perfect and holds this ratio all the way through the rev range, the bikes flying and will pull into the red line in top gear on a flat road. I have noticed though that there's a tendency at around 2-3k to run slightly rich if you back the throttle off for a split second and then nail it - the gauge shows it dipping to 10.2:1.
Anybody got any thoughts on the ratio I'm running. I've always taken 11.5:1 as being ideal for power but is slightly rich. Mines consistently just below 12:1 on a Wide open throttle.
I'm running :-
2.66 needle jet
3rd clip from the top on the needle
158 Main jet
The bikes fitted with the early clam style airbox - I went for this option because the standard airbox didn't appear to flow enough air at higher RPM.
Any Idea where I can main jets between 150 and 158?
Yesterday's weather was perfect for a spot of engine tuning so I rigged up my PD with my air fuel ratio meter. There's a stretch of motorway near me that has a long steady climb that is perfect for load testing.
After a few runs and a couple jet changes and needle adjustments I ended up with what appears to be the perfect set up. This is a full throttle run in fifth gear from around 60 Mph. The spike at 12 seconds is me rolling the throttle off.
It looks nigh on perfect and holds this ratio all the way through the rev range, the bikes flying and will pull into the red line in top gear on a flat road. I have noticed though that there's a tendency at around 2-3k to run slightly rich if you back the throttle off for a split second and then nail it - the gauge shows it dipping to 10.2:1.
Anybody got any thoughts on the ratio I'm running. I've always taken 11.5:1 as being ideal for power but is slightly rich. Mines consistently just below 12:1 on a Wide open throttle.
I'm running :-
2.66 needle jet
3rd clip from the top on the needle
158 Main jet
The bikes fitted with the early clam style airbox - I went for this option because the standard airbox didn't appear to flow enough air at higher RPM.
Any Idea where I can main jets between 150 and 158?
