Sam's 'Best Scrap Available' BSA Tracker
By Ross Sharp - 25 Apr 17
Bikes, beer and welding, sounds like the perfect day to me. Sam from Scotia Welding spends his days fabricating equipment for the micro brewing industry but has form when it comes to bike building. Back in the nineties he competed internationally in sidecar racing and even achieved the accolade of best newcomer at the Isle of Mann TT - hat's off Sam. Five years ago the custom itch needed scratching again and after a couple of Ducati restomods he found himself at a mate's house staring down the barrel of this bastard of a project. Said friend was getting rid of a Yamaha XT600 so Sam snapped up the engine and let the rest go the way of the eBay. The intention was to knock-up a fresh frame but history played a trump card "I had a 1971 BSA B25ss oil-in-frame chassis in the back of the shed which had gathered many years of dust and rust. I bought this bike in 1978 as a 250 after seeing it when I was on my paper round but it disappeared, a year later I got a milk round (better money at £10 a week) and was delivering in another area when I noticed the bike lying against a wall in a sorry state. Next day I slipped a note under the seat asking if it was for sale. A month later I bought the bike for £100 but it turned out it had run the big end, so this was to be my first introduction getting inside an engine. I approached a local lad who was into British bikes to teach me a bit of mechanics. After 18 months I finally had the bike ready for my 17th birthday. After passing my test I fitted a 5TA 500 Triumph motor into the chassis, then a 441 Victor. Eventually the project was broken up and sold-off but I kept a hold of the frame."
A few decades later, inspired by café and tracker builds he'd seen Sam got stuck into the BSA once again. The chap who'd shared his mechanical knowledge all those years ago had a BSA A65 with the slimmer, more attractive fuel tank from an export model, a similar unit was hunted down which set the rest of the build in motion.
The XT engine was stripped, soda blasted and painted externally. Inside the bores were rehoned, pistons received new rings and a fresh timing chain installed just to be on the safe side. Joy Engineering reprofiled the cams and the head was treated to an enlarging of the inlet and exhaust ports by local tuner Geoff Bell. Allen's Performance supplied Keihin CR carbs, the stock ones were knackered, along with handy setup knowhow. The stainless exhaust was a bit of a busman's holiday according to Sam "I am surrounded by pipework on a daily basis when building the breweries, instead of going for the normal route and making a 2-into-1 I opted to take the headers from 1" ¼ to 1" ½ to allow the engine to breathe, finished-off with a small pair of reverse megaphones which I formed over an old fork leg." Once running properly the XT motor was fine tuned on the Dyno at Ian Murray Motorcycles in Edinburgh.
The subframe is T45 tubing, bent to allow for a decent amount of rear wheel travel which comes courtesy of a rising rate swingarm from a 1984 Kawasaki GPZ. This wasn't guess work but a recommendation from flat track champ Stan Millard. Sam chopped through the rear pivot enabling it to be mounted to the back of the engine and therefore did away with the monoshock setup. Hagon specced a pair of adjustable, custom 2810 shocks to match the progressive fork springs. The fork itself is a Paoli 35mm conventional setup from a Ducati Pantah, left over from a previous project but now re-chromed and rebuilt. The lovely gold wheels are also from the Pantah, wearing Avon Road Riders.
Unfortunately the Pantah's brake discs were long gone and seeing as they're so expensive a pair of Brembos from a Monster 620 were modified to fit. Master cylinders are from a Triumph Sprint with levers and reservoir from the Far East. The rear master cylinder was liberated from the Monster and adapted to work with the Pantah disc and caliper. The floating caliper mount and rose-jointed torsion bar are Sam's own work, as are the alloy rear sets.
Motogadget's M-unit system is at the heart of a new harness, complete with Motoscope Mini speedo and M-button switchgear, all powered by a lithium battery and Dyna coil. Small LED indicators are modern, as is the 4½" Hella headlight but that blends-in thanks to the Ceriani brackets. The rear light is grafted into a scalloped section of 60mm tubing.
Finally the paint scheme was chosen, Grabber blue (Ford Mustang) for the fuel tank and Wimbledon white (Ford Transit) for the powder coated frame. Everything else has either been anodised black or zinc passivated. You won't hear the sound of a rattle can in Sam's shed.
Next up on the bench is a Ducati TT2 which will feature Sam's own T45 tubed chassis and a 600 Pantah engine. We can't wait for that one and will definitely report back when it's finished.
Images by Dougie Johnston
If you need a Micro Brewery building check Scotia Welding here