Two years ago, the first ever BMW Motorrad Days Classic Boxer Sprint took place in Garmisch-Partenkirchen and proved to be a fantastic spectacle for all visitors. Back by popular demand for 2015, 32 riders of classic BMW bikes will compete against one another on a 200 metres track for the Classic Boxer Sprint crown. Among the motorcycles hoping for glory is this wild, turbo-charged creation from VTR customs. Worried? You should be…To build a competitive racing motorcycle the assumption is you need the very best of modern technology. But what if that race is the popular Classic Boxer Sprint to be run at BMW Motorrad Days 2015 and Glemseck 101, the home of Sprint? In the case of VTR Customs and its 1988 R 80 RT Polizia Uno ‘P1’, modern tech and ageless design meet head on.In the bowels of BMW Motorrad dealer Stucki 2 Rad Center, Switzerland, there lives a mixed breed of urban customisers and racing fanatics under the banner VTR Customs. To date, these men and women have built numerous café racer and brat bikes from the weathered remains of classic two-valve Boxer-powered BMW bikes.Such is the quality of design and build of VTR’s urban custom bikes, they quite often have little or no stock to show for the hard work involved in creating such machines. But then one day, a collective decision was made to build an example machine that wasn’t road legal but would still promote everything VTR Customs could dream of and fit to a donor bike.A donor bike was found. Actually, three of them to be more precise – and all ex-police R 80 RT patrol bikes from the Italian-speaking division of the Swiss Police force. “We are always looking for bikes that we can use as basis for customisation,” says Daniel ‘Dani’ Weidmann of VTR Customs. “We will buy as many as we can because the classic Boxers are obviously becoming very sought after.”Because Dani races in the Swiss Supermoto championship and many of the Stucki 2 Rad Center and VTR Custom technicians are also race technicians, it was a simple decision to create a proper café racer, one that would, hopefully, be very quick. This would also mean it wouldn’t be road legal and, therefore not get sold, so could spend the rest of its unnatural days on display at the BMW Motorrad dealership as a rolling showcase promoting VTR Customs.The obvious arena for the proposed race bike was originally the annual and best café racer festival Glemseck 101, where the competitive Boxer Sprint Classic is held. But with the success of the first BMW Motorrad Days Boxer Sprint Classic held at Garmisch-Partenkirchen in 2013, the draw of a repeat sprint event for 2015 (3-5 July 2015) was too much and now the mission to complete the VTR Customs sprint race bike is in full swing.Polizia Uno ‘P1’ is the tag name for the sprint bike presently being built. As said, it is a 1988 R 80 RT that originally ran with police specification lights, fairing and luggage equipment. Today it only carries a few reminders of its former glory days, such as scars and the original blue emergency light. The ‘Polizei’ (Police) logo on the fuel tank isn’t the original Swiss / Italian logo but the German equivalent as a kind of homage to the country of that gave birth to the classic ‘Boxer’ engine design.Now, while ‘P1’ looks to be a clearly defined café racer built from many period spares and one-off fabricated parts, there is a whole heap of serious racing and performance technology attached to the R 80 RT’s 27-year-old engine and chassis. All of which is totally alien to a bike of this era.Fuel supply to the blue-printed engine is now by fuel injection. The original twin carbs have been ditched in favour of a VTR Customs ‘home-made’ injection system. The actual types of injectors were sourced by Dani and his staff via eBay. The ECU system to control timing and injection is to remain secret for now. However, Dani has revealed it is a programmable system and is easily done so by his in-house race technicians. A switch located on the top fork yoke gives the rider instant access to selectable, predetermined ECU-stored fuel and ignition maps.If the fitment of fuel injection wasn’t enough, there is also the added spice of a Rotrex supercharger. It’s a belt driven ‘charger’ that takes its drive from the former alternator assembly. The mounting for the charger, outrigger bearing plate and the various pulleys have all been fabricated by VTR Customs. Calculations for the supercharger’s gearing to ensure maximum flow from the compresser wheel (impellor) at low rpm were also done by the VTR team, as was the required final drive ratio to net maximum acceleration. There is no pressurised airbox (plenum chamber) because the forced air intake is pushed directly into the inlet stubs of each cylinder head.Last but not least is the addition of a compact N.O.S. system – a Nitrous Oxide injection System – that it is also delivered to the fuel path. Nitrous oxide is used to cool the intake air, which in turn increases air density to give greater oxygen content to encourage greater burn rate. If all of the attached technical wizardry sounds a shade overkill then you have to remember that ‘P1’ is built to cover an eighth-of-a-mile as quickly as possible. In simple terms the R 80 RT has to beat the bike in the next lane to the finish line.All of the above work is still ongoing. ‘P1’ is up and running but VTR Customs have static tested the bike. “We have to work hard to get the bike completed. The engine has been stripped and built as the original design. The only difference is the heads flow better and the connecting rods have been replaced for stronger items. We have seen some big flames from the exhausts so it will look exciting at the events.”The next for VTR Customs is running the bike in full race mode. At the moment the workshop is waiting for a pulley belt to appear that will route around the pulley wheels and connect the supercharger to the alternator driving point. Dani hopes to have ‘P1’ fully functional by the end of June. Next stop for VTR Customs and ‘P1’ is a bike show in Switzerland at the end of June before the gladiatorial stage of BMW Motorrad Days 2015 and its Classic Boxer Sprint challenge on Saturday 4 July.For more info on how you and your two-valve glory or your custom R nineT can participate at the BMW Motorrad Days 2015 Classic Boxer Sprint in Garmisch-Partenkirchen, contact: firstname.lastname@example.org, give a brief introduction of yourself and add a picture of your pride and joy. See you there.
June 2015 | © BMW Motorrad
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