Like thousands of others, I have registered for Eroica Britannia. There are of course "rules" for the type of bike you ride. These are actually more like expectations or recommendations for the type of bike you will take, as there is no formal scrutineering.

Although I have a few bikes that would fill the bill, ranging from a 1951 Raleigh Lenton. and the 1950 Calla French tourer to modern retro-styled steel framed bikes that would fulfil the requirements, I think it would be fun to build something especially for the event.

When I was a teenager riding time trials and road races as a Junior, I saved up all my pocket money and Christmas money to buy a bright red Viking Severn Valley frame from Fred Williams' shop in Wolverhampton. I put the best parts I could afford on it, but not the ones I would have liked. When I went to University, I sold it to buy a Vespa scooter, that I could perch a mini-skirted dolly bird on the back of.

A few years back a fellow CTC member, who mentioned he had a Severn Valley frame in his loft and if I came back in a week or so, he would have it ready for inspection. Of course I bought it and keen to ride it, I quickly had it powder coated and trawled eBay for the components I would have chosen all those years ago, built it up and rode it for a while. The gearing was too high for me and the chain kept coming off, so more work was required! Since 2012 it has been hibernating in my garage, waiting to be awakened. 

A quick word about Viking Cycles (Wolverhampton). They were one of the biggest UK manufacturers of the 50s and 60s and ran a successful professional racing team. The Seven Valley was their flagship model with Reynolds 531 Double Butted tubing and Nervex Pro lugs. The Viking team won numerous races including the Tour of Britain.

Anyway in need of a revival I sent the frame away to my friends at Sven Cycles in Weymouth to be repainted in the proper Post Office red team colours of the 60s and started thinking about parts.

have built or prepared several customer bikes for Eroica events and more important than "the rules" is building a bike suitable for the "the ride" Remember a lot of it is off road on gravel tracks or other poor surfaces, so the correct choice of wheels and tyres is vital and we are in The Peak District so expect some hills and select gearing accordingly. 

So what parts do I have already? The Campagnolo Record high flange hubs, derailleurs and shifters are perfect, but the Rigida Chrina rims don't look "right" for the era. Also the lovely GS chainset looks the part, but the 53/42T gearing with a 14-24T freewheel is too high for me.

A bike of this era, originally equipped with 27 x 1 1/4" (630 x 32) rims for training and   everyday riding (people generally only had one bike in those days) but with brakes adjustable for 700C sprint rims and tubulars for racing and time trials, allows nice wide (and comfy!) tyres anyway. I had already decided to go with classically styled but beautuflly shiny Velo Orange Paris-Brest-Paris rims, which are available in both sizes. The question was: which size? Not as straightforward a decision, as it might seem at first. Factors to take into account were:

• Risk of the pedals striking rough ground with the 172.5mm Campagnolo cranks originally fitted.
• The Severn Valley frame size is slightly larger than ideal for me.
• Choice of tyres is better with 700C

As I had already decided to change the crankset to lower the gearing, so I have the opportunity to fit shorter cranks and 700C is only 4mm less radius than 27, so I have chosen 700C rims.

Using the slightly smaller 700C, there may be enough clearance to fit 36-38mm tyres for the event. So this week I shall be mainly building wheels. To be continued...