Ypsilon 1925, Blackburne – Various Contributors

This bike which bears more than a passing similarity to a 1925 Cotton, is on a photocopy of a page of an unknown book (P1102) given to me by my friend Gordon Hallett who is an Italian bike enthusiast. He can’t remember where it came from but we think as I sometimes fraternise with his friends in the Italian Motorcycle Club and am known to witter on about Cottons it may be from someone I met there. Gordon is going to consult with likely culprits (it’s a very small club!).FIG 1

Ypsilon is the Greek letter Y, not to be confused with Epsilon, the letter E.

The following is a tidied-up version of a Google translation of the original Italian text. Apologies to Italian speakers

The YPSILON motorcycle, which was launched in May 1925, has a single-cylinder Blackburne engine which is inclined and of 71x88 mm, [being] equal to 348cc and [has] overhead valves.

The lubrication system is ‘modified’ with the introduction of two small rotary gear pumps (presumably a dry-sump system. Drilled crank?). A supply and scavenge pump {is} enclosed in a single body and mounted on the chain cover of the magneto, driven from the magneto by means of a shank coupling, a special warning light mounted on the tank allows you to check the regular circulation of the oil.

The Ypsilon also features:

Three-speed Burman gearbox.

Triangular tube frame similar to that of English COTTON motorcycles.

Terry saddle. But mounted on American-style. blade springs.

The motorcycle comes with American-style ‘parallel forks of the original type’? (They don’t look like Castle-type Harley forks. Ed.)

Expansion brakes, removable wire wheel [s]

The example shown is probably the only one built.

The motorcycle was presented again at the VII Cycle and Motorcycle exhibition held in Milan at the end of 1925.

After that it was never heard of again.

The caption suggests the bike was built in Torino (Turin)

FIG 2

Notes:

Gerry Allen who wrote the article ‘Cotton Copy’ on frames very much after Cotton (CP Sept 22), writes:

There were several firms who copied the Cotton triangulated frame, (the Wardill was perhaps the most blatant) and this could be another. Italians took a fairly relaxed view on patents and copyright (Benelli 500-4?)..It would appear to differ from the proper Cotton in only having 2 top tubes linking the steering head and rear wheel, vs 4 of the true Cotton.
As to forks and hubs, early Ceriani and Grimeca? Interesting bike (seems to have a centre stand, advanced for 1925), although with the exhaust run I wouldn't fancy ear'oling on right hand bends!

Looking at the pictures more closely, the arrangement at the wheel attachment seems unusual. I vaguely remember an article by Richard Rosenthal in TCM in which he described a system whereby the wheel spindle rotated in bearings, instead of the normal clamped spindle with the hub rotating around it. I wonder if the Ypsilon used this approach?

Also, our archivist, Charles Cotton Writes

Thanks for the photos, I have never come across an Ypsilon which gives me the opportunity to say "What's a Ypsilon? Never heard of them.". It does have similarities with the Cotton including the horizontal chain stay. FWC mentions Grigg and Mackechnie in his notes made for Titch Allen, The prototype Wardill was constructed by Griggs using their frame hence the connection with Cotton, Wardill later went on to use their own frame.

Thanks to the CottonOwners and Enthusiasts Club and Chris Sawyer for the above.