Dynatech and Wal-Mart have countered, denying negligence and claiming the 14-year old boy was careless and negligent in his use of the bike, reports the Marin Independent Journal.
Debbie Wills claims the front wheel of the Dynatech fell off while her son was riding in April 2003 and he was catapulted over the handlebars in April 2003.
A complaint was filed in Marin Superior Court a year ago, and this was amended yesterday with further details including the fact that Mr and Mrs Wills claim Wal-Mart could not supply a manual for the bicycle when asked at the point of purchase.
A manual was obtained directly from Dynatech in May 2003, a month after the boy was injured.
Similar to most bicycle manuals, this said: "Correct adjustment of the axle nuts or quick release levers is vitally important to avoid an accident caused by loose wheels."
According to the Marin Independent Journal "neither Jeremy nor his parents knew that the wheel was meant to be removed easily and would loosen over time."
In an earlier, unrelated case, counsel for a major US bicycle manufacturer told BikeBiz.com:
"Virtually all 'defective quick release' claims that I have seen relate to an improperly used quick release. Either the consumer has ridden with the QR open; ridden with the QR closed like a wing nut (rather than closing it over the cam); or ridden with insufficient tightness to the adjusting nut to engage the cam. You can generally determine this by examining the dropout surfaces, which will show the marks left behind as a consequence of the loose clamp force.
"We take great pains in our owner's manual to explain how to use a QR, as do most good cycling books."
In the past three years, Dynatech has recalled nearly 100 000 bicycles in three separate recalls.
The attorney hired by the Wills family has a successful track record: in 1995 he won $3.4m for a Tiburon man who suffered head injuries and developed epileptic seizures after crashing on a mountain bike.