Fratelli Brambilla Guzzi Parabolica
By Ross Sharp - 01 Feb 17
These days Formula 1 finds itself in torrid times, greed and politics have spoiled what was once a rarely paralleled gladiatorial spectacle. In them good old days of two-foot-wide tyres, flames and gargantuan levels of bravely, engineering seemed at the pinnacle of purity. So imagine growing up in the paddocks of the F1 circus and watching your dad duke it out against Hill, Fittripaldi, Lauda, Hunt et al. Monza local Vittorio Brambilla had an illustrious racing career on four wheels but started out on two, winning the 175cc Italian Championship in 1958. No surprise then that Vittorio's sons Roberto and Carlo have the quest for horsepower ingrained in their DNA. The brothers were given the perfect grounding in life thanks to their father passing on his mechanical knowledge and passion for engines. Now in their fifties Roberto and Carlo are still twirling spanners, developing new parts and thanks to a range of high performance engine components produced in-house they've built a reputation as go-to guys for power hungry Moto Guzzi owners. As a rolling business card this 1979 1000SP has been given more than just a quick tune-up. As with anything scrutinised by a stopwatch, the bodywork is functional and lightweight. The fairing and seat unit is fibreglass and the gorgeous alloy fuel tank is hand beaten, the old fashioned way. Öhlins piggyback shocks and a matching fork are from a more modern machine but the really juicy stuff is hidden inside that iconically shaped power plant. You either love a round barrel Guzzi or you don't, there are few engines that get me as hot under the collar as a highly stressed v-twin from the banks of Lake Como. The guys started at the heart of the motor and shaved 1.5kgs off an 850 crankshaft before balancing and polishing it. The flywheel is wafer thin ensuring this inherently lackadaisical twin now spins-up like a prototype racer. The redline is currently set at 10,000rpm at which point 115 horsepower is on tap. Two billets of titanium were then bolted to the 5-axis CNC mill and machined into superleggera, H-section conrods, now 20mm longer at 160mm to reduce the stroke, and therefore capacity to 975cc. CPS from Turino forged a pair of high compression, slipper pistons especially for the project, kept below melting point by a brace of oil pumps, piston cooling jets and a Setrab heat exchanger with Kevlar oil lines by Earles Performance. These engines tend to breath a bit through the oil system when revved hard so a handmade alloy catch tank doubles-up as a splashguard ahead of the rear wheel.
The valves are massive with 3-angle seats, 51mm inlet and 43mm exhaust, controlled by roller rockers, hardened steel tipped, titanium pushrods, a Brambilla-spec high lift camshaft and lightened tappets. A hardened and anodised 7075-T6 alloy pulley is in charge of timing via a fully programable twin spark ignition system. Hardened cylinder studs and die-cut head gaskets should keep the power from leaking out and a straight gearbox transfers all of that engineering effort to the rear wheel.
The stock wiring harness has been replaced with a simplified race loom, whilst maintaining road going requirements such as lights and a Motogadget speedo.
A pair of Lectron carbs feed the beast and a Brambilla titanium exhaust system dispenses of the abused gases. There is a stainless muffler fitted but I've just watched a video of the bike running on the bench.... a silencer it is not! I've owned a couple of Guzzis, ridden a few and loved them but I've not heard one rev quite like this, to say that it's angry is somewhat of an understatement. It barks like one of the Cosworth DFVs that the brothers would have enjoyed so much as children, watching their dad wrestle his orange March around the world's most infamous circuits.
Perhaps not the most traditional custom bike we've featured but to know that the spirit of seventies Formula 1 lives on inside this project certainly does it for me.
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