Post by buttybach1932 on Aug 24, 2023 9:45:34 GMT
SOS CONVERSION.
The first watercooled Villiers engines to become commercially available were produced by SOS. SOS Motorcycles had started production in 1927 in Hallow Worcestershire. Their distinguishing feature was the lugless electric welded steel frame. The frame design was created because there was no gas available at their factory in Hallow to allow the production of traditional tube and lug brazed frames.
In 1933 SOS introduced the 148cc Model KUW and 172cc Model KW fitted with watercooled engines. The SOS designed watercooled top end was fitted to a Villiers 172cc Villiers TT Super Sports type bottom end with Villiers Autolube system. Both engine capacities used a common 67mm stroke. The SOS design consisted of a detachable cast iron watercooled cylinder head and a cast iron twin exhaust port watercooled cylinder barrel.
The 148cc watercooled engine was only listed for 1 year but the 172cc version was available until the SOS stopped producing motorcycles in 1939.
A number of years ago a member of the Vale-Onslow family brought the original timber patterns for the barrel and head to a Stafford Show so hopefully they still survive.
In 1934 Villiers introduced their own 250cc watercooled engine, built on the Mark XIV-A 63mm × 80mm longstroke bottom end with Autolube system. The engine was fitted with a detachable aluminium cylinder head and had twin exhaust port spigots that sloped downwards so it is easy to identify. This engine was also used by Vincent HRD in their lightweight model.
In 1939 SOS introduced two 346cc watercooled models the FW and GW. I have not been able to find any information on the 346cc watercooled engine but in the SOS model listings it is identified as a Villiers engine.
Butty Bach
The first watercooled Villiers engines to become commercially available were produced by SOS. SOS Motorcycles had started production in 1927 in Hallow Worcestershire. Their distinguishing feature was the lugless electric welded steel frame. The frame design was created because there was no gas available at their factory in Hallow to allow the production of traditional tube and lug brazed frames.
In 1933 SOS introduced the 148cc Model KUW and 172cc Model KW fitted with watercooled engines. The SOS designed watercooled top end was fitted to a Villiers 172cc Villiers TT Super Sports type bottom end with Villiers Autolube system. Both engine capacities used a common 67mm stroke. The SOS design consisted of a detachable cast iron watercooled cylinder head and a cast iron twin exhaust port watercooled cylinder barrel.
The 148cc watercooled engine was only listed for 1 year but the 172cc version was available until the SOS stopped producing motorcycles in 1939.
A number of years ago a member of the Vale-Onslow family brought the original timber patterns for the barrel and head to a Stafford Show so hopefully they still survive.
In 1934 Villiers introduced their own 250cc watercooled engine, built on the Mark XIV-A 63mm × 80mm longstroke bottom end with Autolube system. The engine was fitted with a detachable aluminium cylinder head and had twin exhaust port spigots that sloped downwards so it is easy to identify. This engine was also used by Vincent HRD in their lightweight model.
In 1939 SOS introduced two 346cc watercooled models the FW and GW. I have not been able to find any information on the 346cc watercooled engine but in the SOS model listings it is identified as a Villiers engine.
Butty Bach
