The task now is jetting the CV carbs. The first step is to make sure the pilot jets are clean, the float levels are set, and the needles and needle jets are not worn. It is a good idea to replace the needles and needle jets if they have over 20,000 miles on them. When all is good I go to the next step.
Step 2 is to hook up the lambda meter and drive around while looking at the fuel/air ratios. I monkey around with the pilot jets and needles to get the mixture within the 12:1 to 14:1 range during normal street use. The mixture will be on the richer side during hot days and on the leaner side during colder times.
Step 3 is to put the bike on the dyno and to adjust the main jets to produce maximum power.
Step 4 is to recheck the pilot and needle settings during actual use using the fuel/are mixture gage.
A few things to be careful about. Gasahol can give a "weak mixture" feeling during low throttle acceleration. Carb jetting done by feel can lead to an overly rich mixture in an attempt to cure this. My method is to set the mixture to stoicho or slightly leaner and to live with the problem.
Sometimes it is impossible to get the mixture correct at some throttle settings and rpms. Reversion might be the problem. It was on the last engine and an overly rich mixture probably lead to lots of top end wear. That, and flooding the engine to start it on cold days.
This engine is built with the standard Triumph cams, the standard carbs and headers, Triumph off-road mufflers, and the inlet lengths are the same as with the standard air box. The only changes are higher compression, more displacement, a ported head, 2mm larger intake valves, and a stage 3 spark advance curve. The reversion is gone and I can use an enrichener circuit, rather than flooding to start the engine. The motor runs really well. It is the smoother than it has ever been and lots of power at all rpm. Credit Revco Pecision for balancing the crank.
The big difference this time around was using PipeMax to design the motor. Carbs, cams, valves, etc. are all sized to choke at redline, and not any higher. This gives me maximum port velocities during use.