He found the plans on the internet and has spent six months perfecting the design.

And now retired carpenter John Phillips is ready to hit the road for a three day charity ride on an electrically-assisted bicycle he built himself.

The 70-year-old will pedal from Hunstanton to Quidenham, near Attleborough, to raise money for East Anglia's Children's Hospices and has been spotted zipping along the country lanes near his home in preparation for the challenge,

Mr Phillips, from Shipdham, near Dereham, can't wait to get started.

'It's going to be so good,' he said. 'I've been planning it for ages and really wanted to take on a challenge and support a good cause at the same time. My friend Ian Goodwin helped me to brainstorm what I should do, helped in the building of the bike and will be supporting me and cheering me on.'

At the push of a button, a battery on the 21 gear bicycle will give Mr Phillips a boost when he needs it, but he will be pedalling most of the way under his own steam.

He has his wife, Dot, to thank for his comfortable ride after she custom-made a cushion for the bike.

In his fluorescent vest, Mr Phillips hasn't been hard to spot as he trains in and around Shipdham, passing neighbours in a yellow blur.

'The kids seem to love it. They wave at me every morning – they must think 'who's that old idiot?',' he joked. 'Cycles have never really interested me before, but this is completely different.'

Mr Phillips, a classic car enthusiast, has supported children's charities for a number of years and volunteered at a children's hospital in Russia 15 years ago.

He responded to a television appeal by Esther Rantzen for tradesmen to give up a fortnight of their time to work at Komso Hospital in St Petersburg.

Since then, Mr Phillips and his wife have been back to Russia six times to deliver suitcases of Christmas presents to the young patients.

The grandfather will be leaving Hunstanton's Tourist Information Centre at noon on September 11 and plans to stop at Sheringham and Great Yarmouth on the way.

He hopes to collect money as he goes and spend some time at the Each hospice once he arrives in Quidenham.

Claire LeLievre, Each Norfolk Fundraiser, said: 'John is dedicated, passionate about supporting Each and proven to be highly skilled with his bike building.

'I hope his efforts will inspire others to donate to his challenge, or to think of doing a fund-raising challenge themselves.'

To find out more about the charity, visit www.each.org.uk or call 01953 715559.