Story and Photos by new Contributor Scott Rook

I had wanted a BSA B50 for many years. They were the final distillation of BSA’s unit singles that won World MX Grand Prix championships with Jeff Smith in the 1960s and were the last competitive factory four stroke MX bikes in the early 1970s. CCM and Cheney built special framed purpose-built racers around the B50 engine that kept them competitive into the mid and late 1970s. The B50 also had the weirdest and one of the most beautifully shaped alloy gas tanks ever conceived for a motorcycle. It wasn’t exactly round but it wasn’t rectangular either. It was dubbed the lozenge. Triumphs had Pear shaped tanks and Harley had Tear Dropped tanks, BSA came out with a cough-drop shaped tank. The B50 was also recognized as one of the last great British singles in a long line of bikes that stretched back to the early teens and twenties. British singles won Grand Prix Championships with great riders like Geoff Duke and John Surtees. Names like Comet, Manx, Goldstar, Venom, Thruxton and Victor were all great British singles. The B50 also performed admirably in road racing and endurance racing, often bettering larger displacement bikes. I wanted a piece of that heritage.

The BSA D/R Kit turned a stock B25 or B50 into a Dick Mann approved dirt racer. Not that Dick ever rode one professionally… [Scott Rook collection]
BSA offered the B50 in three different flavors, the SS or street scrambler version, the T or Victor Trail for light off-road duty, and the bare bones MX for serious off-road use only. There were traits that I liked of each version of the B50. The SS model had the larger 8-inch front Conical drum brake. The T had a 2-gallon polished alloy tank compared to the SS’ steel one. The MX had the single seat and polished stainless fenders. Later MX bikes had a one into two exhaust on the right side of the machine that looked like the desert sleds of On Any Sunday. The various B50s also had some warts. The road going bikes had an ugly electrical box under the gas tank meant to be easily disconnected for off road use. They also had a huge rectangular shaped muffler that dominated the right side of the machine as well as the hideous Lucas headlight and taillight that BSA / Triumph used in 1971-72. The B50 I wanted was something that BSA called the D/R kit. This was a kit that dealers could buy to turn an SS or T version into a serious off roader. It had alloy levers, an MCM spark arrestor muffler that looked more like the 60s Victors had, an MX single seat and a capacitor to replace your heavy battery. BSA claimed that Dick “Bugsy” Mann approved of the D/R kit. If it was good enough for Bugs then it was certainly good enough for me.

The BSA B50 as discovered and purchased in the Fall of 2017 by Scott Rook. Not very nice, but affordable, with good bones. [Scott Rook]
B50s hardly ever come up for sale in western New York. There was the odd B25 for sale on craigslist over the years, but I wanted the big bike. There happened to be a B50 for sale about 3 hours drive from my house at a time when I had some extra money to not only buy the bike, but do it like I wanted. I made the trip with enough money to buy it at full price but negotiated it down to a reasonable amount. My son came with me, and we listened to the Led Zeppelin box set for the 6 hour round trip. I trailered it home and christened the bike “Hammer of the Gods” in honor of our journey to go get it. I had visions of riding the bike on the road to the nearest dirt trail and then effortlessly transitioning into woods riding. A huge smile on my face the entire time. The bike was brown, and I probably should have called it the rolling turd instead.

The rebuild started immediately. The night I brought it home, I took it for a quick run around the block and then started taking off all the stuff that had been done to it over the years. Within a few days the engine was out and the frame was getting stripped for powder coat. We have long winters in western New York which becomes rebuild season. The goal was to have my Dick Mann approved BSA B50 D/R ready for spring. I sent the engine to the foremost rebuilder of B50s in the U.S. Ed Valiket of EV Engineering. Everything else I would rebuild myself. Rebuild season is a time of hope and optimism. All the parts you have gathered start to come together to form this thing that has only existed in your brain for years. Winter turned to spring and then summer. The B50 wasn’t ready. The engine was still in another state as was the alloy gas tank that I had sent out to have the dents removed. By August everything had arrived and the drive to complete the bike was in full swing. I took it out for its maiden voyage on August 2, 2018. The bike wasn’t finished but the only things left to do were more cosmetic than functional.

Bummer. The curse begins in the Summer of 2018 with a flat tire on the first shakedown ride in Eden, NY. [Scott Rook]

Restorations are never complete when all the parts are done, and the motorcycle is back together. Restorations are really complete after all the running issues have been cleared up and the tuning has been completed which usually takes some weeks and miles. My B50 showed some issues on its first run outside of my neighborhood. The gearbox was giving false neutrals and I couldn’t get it into 4th gear without it popping back out. I thought the gearbox might have some wearing in to do or maybe the clutch needed attention. The other problem was a flat rear tire about 20 miles from my house. The tube stem had been ripped out. I had decided against running a rim lock on the rear tire. My mistake. Clearly this bike needed some more attention. The dirt trails would have to wait. It was August already and I had other bikes to ride that didn’t give false neutrals. The late summer and fall would give way to winter soon and if I wanted to maximize my riding time left then I would take the Triumph or the Dunstall CB750. The B50 got put away until rebuild season started again.

Looks can be deceiving; The only ride of 2019 with the gas tank painted, nos MX exhaust & Malcolm Smith tool bag fitted in Elma, NY. [Scott Rook]
That winter I completely tore down the gearbox and found a broken 4th gear. I also rebuilt the clutch again with all new plates, rubbers, rollers and thrust washers. I was leaving nothing to chance this time. I had also gotten my hands on an nos one into two MX exhaust system and upgraded the rear shocks and front springs. I tried my hand at painting and painted a beautiful black cross on the tank like original and pinstriped it in red. My B50 was going to carry me to those trails this summer and I was going to make Dick Mann proud! I rode it once that year. It was a fall ride in the country. About halfway through the bike started to stutter at anything under 2,000 rpm. I had a feeling it was a bad condenser since that was the only thing I didn’t replace on the ignition system. I made it home and ordered up a new condenser. The riding season was almost over and I had a CB750 to ride that I recently un-cafed, so the B50 got parked. During that rebuild season I tried to address some of the oil leaks and replaced several gaskets and hoses in preparation for the summer of 2020. This was going to be my year.
The nail in the coffin? The curse is real. The first ride of 2020 and another flat tire. [Scott Rook]
On a sunny Sunday morning in late May 2020, I took all three bikes for a ride to the gas station that sells ethanol free gas for the annual start of my riding season. They all ran great as a bike tends to after you haven’t ridden it for months. I couldn’t believe how much fun the B50 was when riding it back-to-back with my Triumph Bonneville and CB750. The B50 did everything the Bonneville did but it was about 100 pounds lighter. It felt great to finally have a relatively smooth shifting and tuned B50 that didn’t cut out at anything below 2,000 rpm. Those trails were going to feel the thump of the Hammer of the Gods. The next day I noticed the rear tire was flat on the B50. Upon closer inspection there was a huge nail in the tire and the rear rim had a hairline crack running across it. This wasn’t just some rough running and a little oil leakage. This was a disaster waiting to happen. I finally said to myself “this bike is cursed”.  I ordered up a new rim and vowed to sell the thing before it killed me.
Danger Danger! A crack in the alloy rim, and a crack in Scott’s confidence. Is it time to sell this thing? [Scott Rook]
I listed the B50 for sale on a few websites and craigslist. I got many responses about what a beautiful bike it was but no serious offers or even any tire kickers. I didn’t ride the bike at all in 2021. I didn’t even wash it or start it up. There was a reason the B50 never sold like the Triumph Bonneville or the Norton Commando. They were simply troublesome machines. The B50’s good looks and the appeal of taking it off-road probably sold thousands for BSA, but once the owner experienced oil leakage and a gearbox with a mind of its own, that appeal quickly faded. I had other bikes to ride and a newly restored Honda CB750 that was taking my time and energy. In the Spring of 2022, I again gave a halfhearted effort to sell the cursed bike and listed it on a few message boards. No takers. I was stuck with this cursed bike. Any dreams of riding to a trail and then going off road had vanished like the B50s oil over the winter. Wet sumped just like my enthusiasm for the rolling turd. Maybe Dick Mann had been wrong. Of course, he never actually used the B50 in competition. He would use a B25 racer for short tracks and then the triple or twin for road races and flat tracks. He didn’t even use the B50 for TTs. I think he knew. Since the bike wasn’t going anywhere, I decided to actually try and ride it. My phone was charged just in case I had to call the wife to come get me. Which she loves by the way. After replacing the battery andchanging the exhaust for the third time it was time for a ride. At first it felt all wrong. I wasn’t used to shifting on the right and braking on the left. The carb slide was set too low, and the bike wouldn’t idle. I pulled into a parking lot and set the idle and air mixture. Then I set off for a ride in the country. The goal was to try and get lost.
The curse reversed: The B50 after the first ride without anything going wrong in the Summer of 2022. [Scott Rook]

It worked, kind of. I still would get a false neutral once in a while, but I think it was down to the shift lever not being in the ideal position and not getting a good purchase on the lever. The new old MCM Spark Arrestor sounded great, but it would pop and sometimes really POP on deceleration. Probably an exhaust leak. The bike ran great after about 15 minutes of me panicking that I would downshift rather than brake. There were no flat tires, it ran great below 2,000 rpm, and the rear rim is in one piece as far as I know. There are still some things to be done. When I got home there was a noticeable oil leak which is down to the frame being overfilled. I added oil after it wet sumped. My mistake. And the exhaust has to be sealed. I think the cursed bike might actually not be cursed anymore. I didn’t manage to actually get lost, but I rode some roads that I had never been on before. This bike needs further miles. Remember all restorations are only finished after they have been tuned and all the issues worked out. This bike took 4 years after its restoration before it was actually finished. It might not be, but it kind of feels like it for now. I might make Dick Mann proud yet and finally ride to one of those trails that don’t really exist in my part of the world (unless you trespass on county land). The Hammer may still live up to its name and thump once more.

Scott Rook started riding motor cycles at the age of 15 in 1989. He traded some baseball and football cards for a beat up 1976 CB750 and has been hooked ever since. He’s a history teacher and father to 3 teenagers in his non-motorcycle life.
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