1971 BSA A65 Thunderbolt
Presentation
This 1971 BSA A65 Thunderbolt is finished in green and white over a dove grey frame and was acquired by the selling dealer on BaT in October 2025. Power comes from a 654cc four-stroke parallel-twin linked with a four-speed transmission with right-side shifting. Details include a two-up seat, a kick starter, an Amal carburetor, a chrome dual exhaust system with aftermarket silencers, wire-spoke wheels, conical hubs with drum brakes, street lighting, Smiths gauges, and center and side stands. Work in 2025 under prior ownership included replacing the tires, fuel lines, battery, and rubber grips. This A65 is now offered at no reserve by the selling dealer in Wisconsin with a clean Arizona title.
The bodywork is finished in green and white paired with bright fenders and set over a dove grey twin-downtube frame. Details include a black two-up seat, a chrome-finished rear grab handle, a steering lock, street lighting, turn signals, folding passenger foot pegs, and both center and side stands. The foot-peg rubber was replaced under prior ownership in April 2025.
The 19″ and 18″ wire-spoke wheels were mounted with Dunlop tires under prior ownership in 2025. Suspension consists of a conventional telescopic fork as well as dual shocks mounted to the swingarm. Braking is handled by drums with conical hubs at both ends, the front of which features a right-side cooling duct.
The chrome-finished handlebar is mounted aft of Smiths instrumentation, including a 150-mph speedometer and a 10k tachometer, and indicator lights are found in the headlight bucket. The five-digit odometer shows 6k miles, although the Arizona title lists the mileage as ~16k, which the prior owner attributed to a clerical error. The handlebar grips were replaced under prior ownership. A keyed ignition is found in the right side panel.
The 654cc four-stroke parallel-twin features an Amal carburetor, a kick starter, and a chrome-finished dual exhaust system with a crossover pipe and aftermarket silencers. In April 2025, under prior ownership, the battery and fuel lines were replaced, fluids services were performed, and the valve clearances, carburetor, and chain tension were adjusted.
Power is routed to the rear wheel through a four-speed transmission with right-side shifting and a drive chain with an upper guard.
Sold on 10/31/2026 for USD $5,300 to WinterViper95
Bids & Comments
WinterViper95 0
Bid
Oct 31, 2026 · 19:00
Bid in the amount of $5,300
Coreclassic
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Oct 31, 2026 · 19:00
Bid in the amount of $5,200
WinterViper95
Bid
Oct 31, 2026 · 18:58
Bid in the amount of $5,100
Coreclassic
Bid
Oct 31, 2026 · 18:58
Bid in the amount of $5,000
WinterViper95
Bid
Oct 31, 2026 · 18:58
Bid in the amount of $4,900
Coreclassic
Bid
Oct 31, 2026 · 18:57
Bid in the amount of $4,800
WinterViper95
Bid
Oct 31, 2026 · 18:57
Bid in the amount of $4,700
Coreclassic
Bid
Oct 31, 2026 · 18:57
Bid in the amount of $4,600
WinterViper95
Bid
Oct 31, 2026 · 18:57
Bid in the amount of $4,500
Coreclassic
Bid
Oct 31, 2026 · 18:56
Bid in the amount of $4,400
WinterViper95
Bid
Oct 31, 2026 · 18:56
Bid in the amount of $4,300
Coreclassic
Bid
Oct 31, 2026 · 18:56
Bid in the amount of $4,200
WinterViper95
Bid
Oct 31, 2026 · 18:55
Bid in the amount of $4,100
Coreclassic
Bid
Oct 31, 2026 · 18:55
Bid in the amount of $4,000
WinterViper95
Bid
Oct 31, 2026 · 18:55
Bid in the amount of $3,900
Coreclassic
Bid
Oct 31, 2026 · 18:53
Bid in the amount of $3,800
Oct 31, 2026 · 17:47
@Sumser When the 1971 BSA-Triumphs were released to the public, road testers complained that the seat height was taller than previous bikes. For 1972. the seats were re-contoured and the top frame tubes were lowered slightly. Similar to the lukewarm reception to the styling, it came down to what people expected at the time. Looking back, the seat height doesn't seem to be an issue, and the styling has become cool.
Oct 31, 2026 · 17:44
I agree @sodoffyoutosser on the seat height “issue”. It’s funny how some “facts” get carried over throughout the years. The only “issue” with the seat height on these OIF BSA’s was in the minds of the magazine writers of the time. Yes, the ‘71’s were 1 to 2 inches taller (depending on the model) than the previous models, but I have owned several OIF Beezers over the years and currently own a ’71 Firebird Scrambler, am 5’ 9” tall with a 30” inseam and have no “issue” at all with the seat height.
@seller some lucky buyer is going to take home a stunning example of a period BSA!
@seller some lucky buyer is going to take home a stunning example of a period BSA!
Oct 31, 2026 · 15:42
Not a bike guy, know little about BSAs, but this is the best looking BSA I've ever seen!!
Oct 31, 2026 · 14:24
Too bad it lost its original mufflers, but the Emgos are pretty close in looks.
The seat height issue is purely aesthetics. Due to the oil bearing frame (vertical tube behind the carb) the front of the seat needed to be higher. I think I read this was fixed to some degree in '72. Definitely fixed for '73 and on Triumphs. It doesn't bother me anymore. This one's a great looking bike.
The seat height issue is purely aesthetics. Due to the oil bearing frame (vertical tube behind the carb) the front of the seat needed to be higher. I think I read this was fixed to some degree in '72. Definitely fixed for '73 and on Triumphs. It doesn't bother me anymore. This one's a great looking bike.
Oct 31, 2026 · 01:17
What is the “seat height” issue mentioned here?
Oct 30, 2026 · 22:14
This popped up and I thought wow, what a great looking bike. Then I realized it was my old bike!! I can confirm this is a low owner, low mileage original bike. All my best to the next owner.
Oct 30, 2026 · 19:55
also, should add that this one looks superb!
Oct 30, 2026 · 19:50
Yes, the 71' and 72' BSA 650's (Lightning, Thunderbolt and Firebird in 71' and no Firebird in 72') had the "OIF" frames like the 650 Triumphs. The final year for BSA 650's was 1972. BSA B50MXs were produced into 1973 but no more 650 twins, and finally, seat height was an issue for the OIF BSA 650s, similar to the 650 Triumphs of 71 and 72, although Triumph largely fixed that in later 72'. That said, the 71' and 72' BSA A65's are still excellent handing bikes and great back road burners. I have had a couple of these OIF bikes over the years.
Oct 30, 2026 · 17:46
I'm pretty sure the '71 BSA Thunderbolts and Lightnings also had the engine oil in the frames, hence the "OIF" designation. Like the '71 650 Triumphs.
Was there a "seat height" issue with the BSA's like the '71 650 Triumphs?
Last, was 1971 the last year for USA, BSA 650's or was there 1972 models?
Was there a "seat height" issue with the BSA's like the '71 650 Triumphs?
Last, was 1971 the last year for USA, BSA 650's or was there 1972 models?
Oct 30, 2026 · 17:43
I'm pretty sure the '71 BSA Thunderbolts and Lightnings also had the engine oil in the frames, hence the "OIF" designation. Like the '71 650 Triumphs.
Was there a "seat height" issue with the BSA's like the '71 650 Triumphs?
Was there a "seat height" issue with the BSA's like the '71 650 Triumphs?
WinterViper95
Bid
Oct 30, 2026 · 00:58
Bid in the amount of $3,700
Roadracer289
Bid
Oct 30, 2026 · 00:54
Bid in the amount of $3,400
WinterViper95
Bid
Oct 30, 2026 · 00:52
Bid in the amount of $3,300
Roadracer289
Bid
Oct 30, 2026 · 00:46
Bid in the amount of $2,600
Oct 27, 2026 · 01:49
I was there when these were new and never saw one, ever.
jack vines
jack vines
Jdreamer
Bid
Oct 24, 2026 · 23:58
Bid in the amount of $2,500
bsbviper
Bid
Oct 23, 2026 · 12:04
Bid in the amount of $1,971
Oct 19, 2026 · 12:56
too bad bsa didn't make a unit version of the a10 engine and put it in a lighter frame like triumph did. i think the a65 engine lower end shape looks too much like a 2 stroke. but everyone has their own preferences as to styling. this is a beautiful example tho, glwa
Oct 19, 2026 · 00:46
Buck-a-cc bid!
DaveD
Bid
Oct 18, 2026 · 23:58
Bid in the amount of $654
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