The reason why you should contact a motorcycle injury lawyer for a crash is because it may be hard for injured riders to get compensation without a lawyer.
Some insurance in some states is only available for vehicles with four or more wheels. Personal Injury Insurance Protection or PIP coverage in some states may not carry people who ride motorcycles or motorcylclists. In some states motorcycilsts are not required to carry PIP coverage.
Even if the person riding the motorcycle has a car and owns it the PIP coverage may not be for accidents that occur on the motorcycle.
If the person riding the bike is not insured, they may struggle to pay for the injury and medical bills that prevent them from working due to the injury. By you contacting an attorny immediately after the accident this can help you to get the compensation and collection of information to support your claim.