BSA A70 Lightning Information and Register


BSA A70 Lightning

The BSA A70 Lightning was a 750cc equivalent of the BSA A65 produced for the US market for flat track racing. Raced by stars of the time such as Dick Mann. They were also known as a ‘Lightning 75’. Whilst the bike used the same chassis as the A65 there were the following differences:

  • Standard 930/78+9 carbs but fitted with larger 250 mainjets
  • Increased Stroke (75mm x 85mm)
  • Increased Compression Ratio (9.5:1)
  • Crankcases
  • Crankshaft
  • Crankshaft Sludge Trap
  • Connecting Rods
  • Big End Shells
  • Flywheel and Bolts
  • Timing Side Bush
  • Oil Pump Drive Pinion Washer
  • Crankshaft Pinion
  • Crankshaft Thrust Washer
  • Crankshaft Shims
  • Oil-Pressure Release Valve
  • Pistons and Rings

Colour Specification
Frame and Chassis    All Black except side panels and petrol tank finished in Etruscan Bronze with white bottom and fluorescent linings (currently available from BBB).

Only 200 A70Ls were produced, 102 in June, 64 in July and 36 in August, See the production records below. These can be identified by the engine frame numbers; G June, J August and H July. Out of the 202 A70’s produced, it is believed that most were originally shipped to Baltimore and approximately 23 to California. Although they were released as 1972 models, they are stamped as 1971.

East Coast Distributor
The Birmingham Small Arms Company Inc
BSA Sales Division
PO Box 6790
Maryland 21204
West Coast Distributor
The Birmingham Small Arms Company Inc
BSA Sales Division
PO Box 337
California 91010

For Magazine articles on the BSA A70 Lightning, See;
Classic Bike October 1995 (Features our own A70L)
Classic Bike September 2008

BSA A70 Photo Gallery

BSA A70 Lightning Seattle

Dick Mann with Alastair McQuaids A70 Trackmaster at Beezumph Rally

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Current Bikes in the register

Engine/Frame NumberLocationCurrent StateComments
GE01022Leicester, UKBeing RestoredImported from Randy Baxter in USA
GEO1025Varberg, SwedenFully RestoredDove Grey frame, never resprayed
GEO1027Philadelphia Pennsylvania, USAUnrestoredRider in great condition
GE01030Florida, USABeing Restored 
GE01031Vale of Glamorgan, WalesBasket CaseCases and motor parts only
GE01035Essex, UKBeing RestoredChopperized, Currently undergoing restoration
GE01041Springville NY, USAFully RestoredNY License plate “BZRGZR”. Many updated parts, not a “restoration.” Daily rider since 1973. Acquired from original owner, frame black, tank & sidecovers dark blue. About 40,000miles as of 2010, but expect many more in the near future, as my commute has grown longer as of 2010. I video recorded my last full rebuild (about six hours’ worth) in 2009 on hi-def (blue-ray). As I get older, I want to remember how it was done…
GE01046Ohio, USAAll Original 
GE01054Ashby de la Zouch, UKFully RestoredAs featured in Classic Bike Magazine Oct ’95
GE01055New York, USAUnrestored and Complete 
GE01057West Midlands, UKBeing Restored 
GE01069Oakland California, USAFully RestoredBought about 5 yrs ago for $800 had Rabers in San Jose rebuild motor got from orig. owner who flat tracked raced, then turned it into a bobber in 1972
GE01070North Olmsted, Ohio, USAFully RestoredAll Stock except paint, 12,700 miles
GE01079Wakefield, USAOriginal, Unrestored 
GE01092Atlanta, GA, USAAll Original 
GE01097Rock Valley, IowaOff the RoadBarn find fresh rebuilt engine in an old basket case 68 frame. An older gent lost interest in the project after losing a friend and parked the bike. The gentleman tells me the engine was originally built by Cheney of Sioux Falls, SD. Until today I knew nothing of the A70L significance.
GE01101Melbourne, AustraliaAll OriginalThe bike was imported to Australia from USA by a Harley importer circa 1982. It is mostly original apart from seat recover, tank and side covers painted. It is black frame with dove grey schocks. It was painted blue when I obtained it and had a NC license plate. After getting details of previous owners from NC DMV I wrote to the original owner who advised it was orange when purchased new.
JE01173Vale of Glamorgan, WalesFully RestoredFlat track racer with known history
JE01185California, USAFully RestoredRestored in 1980s, currently in storage.
JE01194Petaluma,CaliforniaBeing RestoredMay put motor in 71 lightning frame.
JE01203Dettenheim, GermanyFully RestoredDonelson Bike from USA. A70 Engine in a A65 Spitfire Frame. Called Spitfire MK5 750. MK4 Lookalike.
HE00163El Cajon, California, USAFully RestoredEx-racebike, flattrack miler. It has an early Ray Hensly-Trackmaster chassis, with Ceriani / Girling suspension & Barnes wheels. For the motor it has an ARD Magneto, Sifton Cams & headwork, ACK clutch cover, & one off magnesium Mikuni carbs that are rare.
HE01121Middletown, OHIO, USAFully RestoredVery Nicely Done, not molested
HE01122Northampton, UKFully RestoredImported from US in bits with broken conrod. Due to be featured in Classic Bike Magazine
HE01136Atlanta, GA, USABasket CaseCurrently a rolling chassis only.
HE01139Tonsberg, NorwayOff the RoadDirt Track seat/tank
HE01142Pontefract, UKFully Restored 
HE01158Mass, USAFrame Only 
HE01159Florida, USAAll Original 
HE01161Seattle, USAFully RestoredOn Disply in office, Pictured above with red tank
HE01166Cross Lake MN, USABeing Restored 
HE01168Nebraska, USABeing RestoredLooking forward to riding it as I hear they are quick!!!!  Have been doing BSAs since the early 70s and even had a goldie at one time
HE01170Christchurch, New ZealandBasket Case Just started this project having won an auction, 90% complete
HE01208Mid Wales White & Red
P50 004West Midlands, UKBasket CasePrototype Number Four

BSA A70 Production Records

Number ProducedDate


A70 Service Bulletin