North Yorkshire Police are appealing for witnesses and dashcam footage following a collision near Skelding, in the Ripon area, on Sunday morning.
The incident was reported by the ambulance service at around 10.25am on 10th August.
It happened on a minor road between Pateley Bridge and Kirby Malzeard, involving a black and yellow/gold Kawasaki motorcycle and a grey Kia Niro.
The road was closed for several hours to allow emergency services to work at the scene and reopened at around 3pm.
Police say the motorcycle was travelling towards Kirby Malzeard, while the Kia was heading in the opposite direction towards Pateley Bridge.
The motorcyclist, a 50-year-old man from Boroughbridge, was airlifted to hospital with serious injuries.
The three occupants of the Kia were uninjured.
Officers are asking for anyone who saw either vehicle prior to the collision, witnessed the incident itself, or has dashcam footage to contact them.
Information can be provided by emailing mark.patterson@northyorkshire.police.uk or calling 101 and asking for Sergeant Mark Patterson or Traffic Constable Matt Carling.
Please quote reference 12250149449.

Harrogate-based Sporting Influence Foundation to tackle 24 climbs in 24 hours
Giant vegetables take centre stage at Harrogate Autumn Flower Show
Alpamare waterpark to be sold to 'protect its future' with private investment
Roadworks causing growing disruption in Harrogate and Knaresborough, officials admit
Yorkshire artist brings Harrogate's Old Market Hall back to life
Martin House hosts first children's palliative care conference
Judge appointed to lead inquiry into North Yorkshire mental health trust
Harrogate group raise more than £40,000 with cycle to Bordeaux
Scotton pub wins Tripadvisor award for seventh year running
Almost 2,000 people sign Knaresborough landslip petition
Police appeal after Range Rover damaged in Knaresborough
St Aidan's teacher recognised at national Teacher of the Year Awards
Bramham Park to host its first Christmas market
Harvest gown unveiled for flower show's 50th anniversary
Ripon's Mario's Restaurant named among Tripadvisor's top 10%
Harrogate Rugby Club reveals plans for clubhouse expansion and padel courts
Police appeal after Lister House minibus vandalised in Ripon
Council urged to "show me the money" and provide evidence of home-to-school policy change savings
Kate Mosse and Prue Leith among stars of Harrogate Literature Festival
Ripon among UK's top cities for missing parcels


