Source: Bike Bound
Velocette Scrambler from South Africa…
In 1933, the Velocette 350 MAC was born, featuring a 349cc single-cylinder high-cam pushrod engine capable of running the 280-lb machine up to ~75 mph. None other than Phil Irving, who’d design the Vincent V-twin in 1936, had designed the 350’s frame, and the Velocette MAC would remain in production all the way until 1960.
“In 1960’s Britain, riders of lesser machines regarded Velocette’s big singles with awe and their owners with envy. Though not quite in Vincent territory, they exuded tradition, build quality and longevity — and commanded a premium price to match.” –Motorcycle Classics
The Velo was a cut above the BSA and Matchless 350’s of the time. Today, we rarely see these bikes converted into specials, as they’re a bit too rare and valuable to cut up. However, our new friend Andy Robertson of South Africa had the vision, spare parts, and machining expertise to create the scrambler you see here…without destroying any original parts.
Andy is a lifelong Velocette and Yamaha DT fan who began building bikes at the tender age of 12 and now manages his local Apprentice Training Centre. With 12 Velocettes and tons of spares in the family stable, Andy looked around and realized he had the makings for a 350 MAC scrambler.
“In the spares was a complete 350 MAC engine that we think had been raced at some point. The plan was always to build it onto a frame and build a café racer, but I already had a 500 Venom café racer which came from the 60’s, so I decided to build a Scrambler — I also wanted to do something together with my dad!”
Andy grafted the front-end of a 1982 Yamaha DT125LC to the 1956 Velocette frame using modern taper-roller bearings, accomplished with spacers and stoppers he custom-machined. The wheels also came courtesy of the DT, while rear shocks are (front) Yamaha Blaster ATV units. The tank is an original Velocette unit, while the mudguards and seat are swap-meet specials of unknown provenance.
Any didn’t want to damage any original Velo parts, so nearly everything was done to be reversible, apart from the RHS trunnion on the RS frame, where he had to weld a plate to locate the DT rear brake. The bike’s reversibility is a point of pride:
“Nothing on the bike is permanent — if I ever decided one day that I wanted a standard Velocette 350 MAC I could convert everything back — that took some planning — I was adamant that I didn’t want to destroy Velo parts!”
He says the finished bike is a lot of fun and sounds the part thanks to the hotter cam from the engine’s racing days.
“It is a fairly heavy bike — the RS frames are pretty solid so it’s not the quickest — my guess is that it’s probably on par with my DT175 — but with a lot more torque!”
Andy is particularly thankful to his old man for all of his knowledge and help.
“He wasn’t all that keen in the beginning — as one might expect from a purist, but he came round in the end!”
Below, we talk to Andy for more details on this lovely Velocette scrambler. The lovely workshop photos were taken by Rozier from Okay Deer for the annual calendar of Andy’s local vintage motorcycle club.
MAC 350 Scrambler: Builder Interview
• Please tell us a bit about yourself, your history with motorcycles, and your workshop.
I’ve been building bikes since I was around 12. My dad bought me three early 80’s Yamaha DT’s — two 125’s and a 175 — and from those three I managed to build up a 125 and a 175. From there it just grew, and I have been a Yamaha fan and DT fan ever since — I have owned 15 DTs over the years and currently have a fully restored 125LC as well as a 175 and a 200.
I am lucky to have a good workshop with lots of space — and in addition, part of my job is to supervise the Apprentice Training Centre where I work, and we always have a bunch of fitters and turners who regularly get “additional training” on extra parts I need manufactured or modified!
• What’s the make, model, and year of the donor bike?
So, the majority of the bike is 1950’s Velocette — we have 12 Velocettes in our stable and a bunch of spares — so I was able to put together the makings of a 350 MAC.
When I was restoring my 125LC I needed a chainguard as well as a kickstart so ended up buying a very tatty complete extra bike. It came with wheels and forks and one afternoon I mocked up something on a Velo frame for a laugh and was surprised at how easily everything seemed to fit together. From there the Scrambler was born.
• Why was this bike built?
We have a few Velocettes in our collection and tons of spares. In the spares was a complete 350 MAC engine that we think had been raced at some point. The plan was always to build it onto a frame and build a Café Racer, but I already had a 500 Venom Café racer which came from the 60’s so I decided to build a Scrambler — I also wanted to do something together with my dad!
• What was the design concept and what influenced the build?
I saw a picture of a Velocette Scrambler on Bike EXIF, and I figured I had enough spares to do something similar.
• What custom work was done to the bike?
Because Velocettes are fairly scarce I didn’t want to chop up frames and irreplaceable cycle parts to make a Special, so actually there is very little that has been modified which can’t be reversed. The entire front-end of the DT fitted onto the RS Velo frame with very little fuss — I made up some spacers to allow modern taper-roller bearings to be fitted and had to manufacture some stoppers to stop the forks hitting the tank but other than that it was fairly easy.
On the rear, I did have to weld a 6mm plate onto the Velo RHS trunnion to locate the DT hub but that can be removed easily if necessary. I made a longer axle for the DT hub but was also able to incorporate the DT chain adjusters into the Velo trunnions, which again was a simple exercise.
The biggest challenge was to manufacture a linkage to allow the RHS DT brake to be operated on the left side of the bike. There I used an old RZ350 gear selection shaft which passed through the pivot point of the Velo trunnion — I raced a PE175 and it had a similar setup, so I just copied that!
I also had to modify a standard Velocette Venom oil tank to allow the fitting of the bigger carb, but Velocette used to do that at the factory anyway for the Thruxton, so I didn’t feel at all guilty about cutting up a standard oil tank. I also fitted a modern type of spin-on oil filter — a modification we have done on most of our Velo’s.
• Does the bike have a nickname?
Velocette Scrambler, I guess!
• Any idea of horsepower, weight, and/or performance numbers?
It is a fairly heavy bike — the RS frames are pretty solid so it’s not the quickest — my guess is that it’s probably on par with my DT175 — but with a lot more torque!
• Can you tell us what it’s like to ride this bike?
It’s a lot of fun — the motor has a cam of unknown origin so it really sounds the part — but as with all Specials, there are things that need to be sorted. Right now the Velo gearbox has a reverse cam gear selector so the 1-up 3-down is not ideal for street riding, and because I have to run a 428 DT chain I could only find an 18T front sprocket that would fit the Velo gearbox — the biggest rear sprocket I can get for a DT is a 52, so the gearing is a bit out — it won’t really pull top gear.
I do have an old YZ125 hub which has the brake and sprocket both on the LHS — just like the original Velo setup, and the YZ’s run a much bigger chain and rear sprocket so that would work — I just need to source some unobtanium YZ spokes!
• Was there anything done during this build that you are particularly proud of?
I guess the fact that nothing on the bike is permanent — if I ever decided one day that I wanted a standard Velocette 350 MAC I could convert everything back — that took some planning — I was adamant that I didn’t want to destroy Velo parts!
• Is there anyone you’d like to thank?
Just my dad – he’s a wealth of Velocette knowledge and was able to offer some really good advice! He wasn’t all that keen in the beginning — as one might expect from a purist, but he came round in the end!
Photography Credit
Rozier from Okay Deer: okaydeer.co.za | Facebook
