(Click for full photo)
1921 - 1930 Sunbeam Royal Sunbeam 1923 Royal Sunbeam
Frame no. 141812.
(according to Pinkerton et al - "Sunbeam Cycles, the story from the catalogues, 1887-1957" - no.140107 was sold on 25.5.1923 and 142400 0n 23.3.23 so it probably dates from that year)
Proportion in bicycles is a subtle matter, generated by lengths and angles: to my eye, this is the epitome of the roadster bicycle, with its 26" frame and 28" wheels - it is certainly handsomer than another bike I have, with 28" wheels but only a 24" frame. I think the length of the head-tube is critical.
The bike is fitted with the "standard" Sunbeam 3-speed hub introduced in 1913 to supersede the Newill "stepped" hub pictured elsewhere on this site. It is effectively a clone of the BSA 3 speed, which was itself a version of the Sturmey-Archer X type made under licence.
This hub has two notable virtues compared to the usual Sturmey-Archer article: first, it is always in some gear, so no risk of groin-crippling pedal slip; second, the wire is slack in low gear rather than top, so that if it fails, it is easier to get home. Why Raleigh (who effectively owned S-A) did not use it on their bikes is a great mystery.
It also has "Roman rims", first made in 1897 and fitted to Sunbeams at least as early as 1902 . These were made of a patent alloy of aluminium invented by Dr Reinhard Isidore Roman, and called "Romanium"
The relevant patents can be viewed at
by keying in GB189907786 (which relates to the making of the rims)
GB189806730 (relating to the use of alloys in bicycles generally)
and GB189806729 (the actual composition of Romanium)