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By Rupert Ratio
Mitchell Collection Bike 1
BSA WD B40 Mk1 1967
Mitchell Collection Bike 2
BSA WD B40 Mk1 1967
Mitchell Collection bike 3
BSA WD B40 GR Mk1 1970 RAF
Mitchell Collection bike 4
Mk2 M (Jordanian Army) 1968
Mitchell collection bike 5
WD B40 Prototype 1965
Mitchell collection bike 6
BSA WD B40 MK1 GN 1969 Royal Navy
Mitchell collection bike 7
BSA WD B40 GB 1969
Mitchell collection bike 8
BSA WD B40 MK1 GB 1970
Mitchell collection bike 9
BSA WD B40 MK1 1969 GN Royal Navy
Mitchell collection bike 10
BSA WD B40 MK1 1970
Mitchell collection bike 11
BSA WD B40 1969 GN Royal Navy
Mitchell collection - bike 12
BSA AWD B40 GA MK1 Australian Army 1967
Mitchell collection Bike 13
BSA WD B40 MK1 GN 1969 Royal Navy
Mitchell collection Bike 14
BSA B40 GR MK1 1970 Royal Air Force
Mitchell collection bike 15
BSA WD B40 MK1 GD - Danish Army 1968
Mitchell collection bike 16
BSA WD B40 MK1 1969
Mitchell collection bike 17
BSA WD B40 MK1 GB 1967
Mitchell collection bike 18
BSA WD B40 MK1 GB 1967
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Other motorcycles in my collection
Non WD B40's

Ratio Rebuilds

Rupert Ratio

Oil pump exchange available

Rupert (Dave) is offering an oil pump reconditioning/exchange service for BSA Unit Single 2 stud alloy oil pumps.

£30.00,  exchange without oil pump drive gear + P&P
Oil pump drive gear can be supplied and fitted if required

Email for details:

Full Engine Rebuilds

Currently 6 month lead in time due to high levels of demand in collaboration with Rupert Ratio (Dave Smith) can now offer complete engine rebuilds, repairs and other services for all BSA Unit singles.

Rupert Ratio, the author of a series of BSA Unit Singles books, is internationally renowned for his knowledge, expertise, skill and attention to detail. 

When this is combined with either using original parts or those that are tried and tested, you can be assured your BSA unit single engine performs to its optimum often better than the BSA factory could achieve and certainly most of those home
mechanics of years gone by.

The cost of a full engine rebuild is based around the two following fixed labour costs:
£100 - engine strip down, assessment and full written condition report with recommendations.
£270 - Clean and rebuild
The cost of parts and other work is dependant on the condition report and any recommendations made and customer requirements

We are committed to using the best parts available - where possible genuine parts will be used

If a full rebuild isn't required, please do not hesitate to make contact and we will be happy to give you a quote

To discuss your requirements, please email on in the first instance with the subject heading "Ratio Rebuilds"

For info contact via email

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