Apart from the series of JPs built by Joe Potts, there were only three other 500cc racing cars built in Scotland - Roy Clarkson built an Iota, Alex McGlashan built a Marwyn and in Leven, Fife two brothers and their friend built a very professional looking car called the MHM 500. They were Jock (JB) and James (JC) Moncrieff and their friend was DY Henderson.

The car was constructed from a modified Fiat chassis, which may have contained parts from a Marwyn as period reports state the Moncrieffs had purchased a Marwyn. However, the chassis was indeed a Fiat and this was recently confirmed by a friend of the Moncrieffs, Alex Fairbairn, and also by the October 1951 advert when the car was listed for sale. The engine was a tuned Triumph Speed Twin, rear engined and, from the look of photographs, driving a solid axle supported on leaf springs. This axle looks very like a Marwyn item. The MHM had a very neat and professional looking aluminium body, which fully enclosed the car. Jock worked as a mechanic at Murieston Garage and the MHM was a very well built machine and was always neatly prepared.

The MHM 500 (Moncrieff – Henderson – Moncrieff) was ready for action by the Autumn of 1948 and it was driven at the September Bo’ness hill climb by Jock Moncrieff who won his class, beating the Marwyn of the very experienced Alex McGlashan. This early success was not to be repeated though and despite several outings at Bo’ness, The Rest and be Thankful, sand racing at St Andrews and circuit racing at Crimond and Winfield, the car proved to be rather too heavy and underpowered. Alex Fairbairn also remembers the Moncrieffs taking the car down to Silverstone but there is no record of it competing there.







Jock Moncrieff emigrated to South Africa in 1952 and advertised the MHM for sale in the Winfield race programme of October 1951 for £250. It is not known who bought the car but it reappeared at Bo’ness in June 1953 re-bodied and re-named as the Hammond 500 Special and seems to have been converted into a two seater, rear engined sports racer. It crashed in practice and was unable to continue. The MHM – Hammond 500 was last seen dumped ignominiously on its side in the rear of a truck in the Bo’ness paddock. It made no further competitive appearances and has disappeared without trace.

Some known results:

Bo’ness Hill Climb17th September 1948,  JB Moncrieff, First

Bo'ness 25th June 1949 James Moncrieff crashed in practice, DY Henderson entered but did not compete
Rest and be Thankful 9th July 1949 Inaugural Event, DY Henderson, Fourth, Jock Moncrieff entered but did not compete
St Andrews Sand Race July 1949, Jock Moncrieff, Second in heat (One Mile Sprint), Third in final (One Mile Sprint)
St Andrews Sand Race July1949,  Jock Moncrieff, DNF, 10 Mile Race
Bo'ness 17th September 1949,  James Moncrieff, Fourth

Bo’ness Hill Climb June 1950, James Moncrieff, Fourth
Bo'ness 30th September 1950, James Moncrieff, Third
Winfield 7th October 1950, Jock Moncrieff, Fourth

Crimond 17th June 1951, HG Barrington, Fourth
Winfield 21st July 1951 HG Barrington entered but did not compete
Winfield  13th October 1951 EG Paterson entered but did not compete

Bo’ness Hill Climb 11th September1953  D Hammond crashed in practice as the Hammond 500 Special

A rather sad end to the Hammond Special at Bo'ness


Our thanks to Kenny Baird, if anyone has any more details or photos, please get in touch.