Connect With Us!

Retrospective: BSA B25 Starfire 250: 1968-1970

1968 BSA B25 Starfire 250.

1968 BSA B25 Starfire 250.

Photo Credit: Clement Salvadori

Clement Salvadori
October 22, 2007
Filed under Retro + Vintage Motorcycle Reviews

(This Retrospective article was published in the October 2007 issue of Rider.)


This little machine was an anomaly when it appeared on the showroom floors in 1968; though it was a rather attractive motorcycle, it was powered by an old-fashioned single-cylinder OHV engine.

BSA had been building 250 singles since 1938, and some dim bulb up in marketing thought there was still a market for a little plodder…if you dressed it up real pretty.

It was a tough engine, slightly undersquare with a 67mm bore, 70mm stroke, having an aluminum alloy head and barrel, with an iron liner, a one-piece forged crankshaft with two flywheels running to keep the vibration down, and a duplex-chain primary drive to handle all that power going to the four-speed tranny. The factory claimed over 20 horsepower at 8,250 rpm—perhaps at the piston dome, but certainly not at the rear wheel.

Back in the 1950s 250cc and smaller motorcycles abounded all over Europe, providing cheap transportation in an economy that was still struggling to overcome the aftereffects of World War II. But as the world’s finances grew stronger, the utilitarian 250 gave way to the Volkswagen, Fiat 500, Austin A40, and the market for these utilitarian machines virtually vanished.

1968 BSA B25 Starfire 250.

1968 BSA B25 Starfire 250.

In the United States during the Eisenhower years this market never really existed, as it was only schoolboys who bought basic bikes with their earnings from a newspaper route, moving up to an old Ford or Plymouth when they could. Proper motorcycles, like big Harleys and BSA Road Rockets, belonged to the small group of enthusiasts most noted for having grease under their fingernails from all the maintenance and repairs that these bikes required.

In 1968 quarter-liter bikes were still popular but as sport rather than utility vehicles. Just about every manufacturer had one or two. Lots were two-strokes, like the Montesa Scorpion and Bultaco Metralla singles, or the Yamaha Catalina and Kawasaki Samurai twins, and a few four-stroke singles, like Ducati’s Mark 3 Desmo, Benelli’s Barracuda, Harley’s Aer­macchi 250 with a race-bred pushrod engine, and the rather unexciting British offerings, the Triumph TR25 and BSA Starfire. Those last two were very similar machines, differing only in styling and badges.

1968 BSA B25 Starfire 250.

1968 BSA B25 Starfire 250.

Since this was essentially a BSA product, we should take a look at its genesis. That 1938 C10 was a flathead engine with separate gearbox in a rigid frame, and after the war an OHV C11 version soon became available, in either a rigid or a plunger frame. The C12, appearing in 1956, used a swingarm frame. 1959 was the year of big change, with a unitized engine/transmission in the C15 Star. In best British tradition the crankcases were split vertically, which usually meant leaving drops of oil wherever the bike was parked. A 26mm Amal Monobloc carb was fitted.

The loop frame used a single downtube mating with a pair of tubes cradling the engine. A shrouded fork and shocks, and a nacelle around the headlight, were the antithesis of the sporting image. Years rolled on, sales were lackluster, and BSA decided it had to change the dowdy appearance. And performance. And name. The 1966 C15 Sportsman got the nacelle ripped off the headlight, open springs on the rear shocks, and a racy little hump at the back of the long, flat seat.
Good, but not good enough. The factory decided to spend some money, and the B25 Starfire appeared on the American market in 1968. A new cylinder barrel was cast, with the pushrod tunnel enclosed behind the newly squared-off fins. (A 441cc version, the B44, was also built, but that is another story.) A bigger 28mm Amal Concentric carburetor was fitted, a “hotter” camshaft, and the compression ratio went up to 10:1. A single set of points (so easy to adjust!) sat inside a little cover on the right side of the engine, and the electrics were 12 volt.

1968 BSA B25 Starfire 250.

1968 BSA B25 Starfire 250.

The very first Starfires to come into this country had the old skinny seven-inch brake drums on both 18-inch wheels, but that was soon changed to a full-width drum on the front. The frame was little changed from the C15, though the fork was improved with a double hydraulic damping system. And the metal covers protecting the sliders had now given way to sporty rubber gaiters! Yes, yes! The shrouding had come off the shock absorbers as well. And the rather dull oblong gas tank became an artfully contrived fiberglass container holding 2.5 gallons of fuel, with glorious sunburst BSA emblems. High test, please, as that compression ratio needed the best. Abbreviated chromed fenders and sculpted side panels and oil tank finished the new look, along with the chrome headlight shell and Smiths speedometer (missing on this one). Very pretty it was, in blue and white.

Put a leg over the saddle, bend down and flip the top bit of the kickstarter out 90 degrees, pull in the clutch and kick through to free the nine clutch plates, open the petcock, tickle the carb, turn on the ignition key in the steering head, and if the battery were up the engine should start in one kick. Maybe two or three if it is cold, because the Concentric does not have a choke. Make sure your right inner thigh does not connect with the cap on the oil tank.

1968 BSA B25 Starfire 250.

1968 BSA B25 Starfire 250.

Click down into first, the cush drive in the clutch smoothes the take-up, and away you motor. In-town work is a bit sluggish as the cam does not really function well at under 4,000 rpm. The fork has over five inches of travel, the shocks almost three, but the springs are on the stiff side of plush. If the road is smooth, the ride is comfortable. Now the oil is warm and you are in the country. If you are a sporting person, you might have sprung for the optional tachometer, but if not, the engine will certainly tell you when it is near the 8,000 rpm line. The speed tops out at almost 80 mph in fourth gear; you are exhilarated and consider the $750 well spent. That is until a Suzuki X-6 250 Hustler blasts by you, shifting into sixth gear at 90 mph; that bike cost less than $700.

For 1969 BSA dropped the price to $695. And added the B25S model, with an upswept pipe, trying to pretend to be a street-scrambler. Too late. By the end of 1971 all the 250s were gone from the Beeza line.

1968 BSA B25 Starfire 250.

1968 BSA B25 Starfire 250.

Related Content

Other stories that might interest you...


4 Responses to “Retrospective: BSA B25 Starfire 250: 1968-1970”

  1. Manuel Teixeira on February 25th, 2013 12:58 pm

    hi guys, im from portugal, and i was thinking in buying a bsa b25 star fire or a b44 victors, do you know where can i find one in the UK?


  2. ANDREW JOHNSON on June 14th, 2014 5:34 am

    Hello Manuel
    I have learned quite a lot about these machines in my life and the B44 is by far a much better machine than the B25
    Hope this comment is of help
    Cheers Drew


  3. keith metcalfe on August 12th, 2014 8:55 am

    hi l own a starfire and am currently up dating it.

    l also use to a t350 Suzuki???

    I can assure you I get more buss out of the BSA 250 then I ever did on the suz.

    less points on my licence more fun round country lanes don’t need the ton up feeling any more done that got the T shirt and got banned ha bit younger then though.
    l would not swop it might even get some thing bigger like a bonny ??
    still dreaming and riding bikes


  4. Paul on May 23rd, 2015 5:37 am

    I have a b25 built as an green lane and is great fun to ride. The amount of people who stop to comment on it is amazing and off road the grin factor, sound is well worth the time and effort spent. I read about how poor the engine is but found it easy to work on and this bike is miles from standard but goes like stink!
    I had a guy on a 500 enfield who was following me ask ” It is a 500 isnt it?” oh no mate 250……………………….


Feel free to leave a comment...
and oh, if you want a pic to show with your comment, go get a gravatar!