One woman was killed and another injured when their 2008 Honda motorcycle crash- ed yesterday on Kaukonahua Road in Waialua.

The fatality was the seventh motorcycle-related death on O'ahu this year, matching the total number of motorcycle fatalities last year, according to Advertiser records.

The operator of the motorcycle, identified by police as a 27-year-old woman, was heading north on Kaukonahua just before noon when she lost control of the bike and crashed into a guardrail. She was pronounced dead at the scene at 12:28 p.m.

Her passenger, a 23-year-old woman, was taken to The Queen's Medical Center in critical condition but was later upgraded to good condition.

Police closed Kaukonahua Road in both directions — from Thomson Corner to the top of the S-turn — to investigate the crash. The road was reopened about 4 p.m.

It was the 19th traffic fatality of the year in Hawai'i, compared with 12 at the same point last year, and the third motorcycle fatality in eight days.

On March 21, Simon Cesar, 19, of Hilo, Hawai'i, was killed when a 2006 Suzuki motorcycle he borrowed crossed the center line of Kipimana Street and struck a utility pole.

On Saturday, 24-year-old Joshua Thurman of Lahaina, Maui, died when he lost control of his motorcycle and crashed into a guardrail on Honoapi'ilani Highway.

According to the National Highway Traffic Safety Administration, the number of motorcycle deaths nationally increased every year from 1998 to 2007. Statistics for 2008 have not yet been compiled.

The increase roughly coincides with a steady increase in motorcycle sales from 1995 to 2005, according to statistics compiled by webBikeWorld .com.

In 2007, there were 25 motorcycle fatalities in Hawai'i.