This is an achievement which still surprises Francis. "When we first started we didn't think you could be 30-years-old and still do this," he said. "Then we hit 30 and got to 35 and thought this is ridiculous and then 40... If Mick and Keith are still going that means I can. McCartney and Cllff are still working at 60. We could still be going at 80!"

Whether the relationship between the band's two founder members, Francis and singer Rick Parfitt, holds out until then is another matter. The pair have been mates since the age of 16, but after spending 40 years together they could be forgiven for getting on each other's nerves.

Francis said: "We don't have rows. We don't get on as well as we used to but we get on reasonably well.

"I have spent more time with Rick than any of my girlfriends or wives. People forget that. We see each other from the start of the day to the end of the day. He's the first person I see and the last. But it's how we get on stage that matters."

The rock veteran said he didn't know whether current groups would match their rock status and still be around in their 60s but thought Radiohead, Muse and Oasis were in for a shot.

He said: "Oasis I think should or could be but while the younger brother still tries to pretend he's 22 it's not going to work. There has to be a point when you think 'I'm quite content. I'm not that person growing up on a Manchester estate anymore'."

Fans heading to the International Centre on Friday and Saturday will be treated to hits spanning the Quo's 40-year career, which started with their 'Pictures Of Matchstick Men' single.

The show will boast state-of-the-art stage backdrops evoking classic Quo moments, something which Francis remains unsure about.

"There will be pictures from various times of our career including pictures taken in the 60s," he said. "Hopefully it will be fantastic. I personally don't like this. If someone is looking at the scene behind me I think do I need to be here? The thing that makes Status Quo what it is, is that people watch them. If they are watching those scenes they aren't going to be watching us."

Francis said he didn't know how well the gig would go down with fans as some of their lesser known earlier material will feature alongside the more traditional Quo crowd pleasers.

"We have had 67 top 100 songs and there are about 17 in any set so there is a big choice and someone is bound to be disappointed if we haven't played their favourite," he said.

"There might be two people stood next to each other – one who wants to hear all the well-known chart stuff and one who likes our unreleased tracks. Everyone is different."

Personal favourites of the guitarist, which may appear on the set list, include Marguerita Time and Rock Till You Drop.

Quo have played in Harrogate numerous times over the years and Francis enjoys playing in the town. "I love Harrogate by the way," he said.