Hello Dave,

As I understand, the modulator does not determine the rpm of the shift, just the pressure used.

I understand that there is a governor that sets a default shift for each gear, modified by the position of a Bowden Cable which transmits throttle position. More throttle = later shift, less throttle = sooner shift.

Check the cable, is should have NO tension at idle position, but no real slack, either. Slack will fool the transmission into thinking your throttle is less open than it is, delaying shifts.

Of course, there could be other reasons too.

Check the cable (use Search for Bowden Cable for a whole lot of posts on the subject) and others will add their knowledge.

Best Regards,
Jim