CHICAGO (CBS) — Although CTA is promising faster trains when the latest round of renovations to the Blue Line are complete, they will not be as fast as riders were promised a few years ago.

In July 2007, then-CTA President Ron Huberman promised Blue Line O’Hare branch riders 70 m.p.h. top speeds.

“Fifteen months from now, we should see tracks restored to the 70 m.p.h. standard so that we can make the Blue Line hum as quickly as possible,” Huberman said at the time.

That round of slow zone repairs failed to hold up, and the 70 m.p.h. promise went unfulfilled.

Now, CTA President Forrest Claypool has said, 70 m.p.h. is not in the cards for the O’Hare line.

“What we’re shooting here for is consistent, reliable 55 m.p.h. trains on our system,” he said Thursday. “Between the slow zone removals, the reliability improvements, the reduced dwell time (stopped time in stations), the power, the signals, those things should allow us to cut 10 minutes off the commute.”

CTA is billing the four-year, $492 million O’Hare branch renovation project as the most extensive work undertaken on the line since it was extended from Jefferson Park first to Rosemont and then to O’Hare in the 1980s.

In addition to the work on the tracks, the signals and the power distribution systems, extensive renovations are planned at stations along the O’Hare branch between Grand/Milwaukee and O’Hare.

Although all CTA trains in service today are capable of 70 m.p.h. operation, CTA limits them to 55 m.p.h.

The only time CTA trains attained 70 m.p.h. was on the Skokie Swift briefly in the mid-1960s.