BST carbon fibre wheels were originally intended for Street and Track use for the superbikes. They found their own way into Drag Racing as the riders immediately recognized the benefit to be gained - this was quite a surprise to BST as they hadn’t targeted that market! The Drag market grew rapidly and that’s when Harley-Davidson, customizers and custom builders picked up on them. The new Black Star line was BST’s response, with the with the many different sizes and fitments offered to specially meet their needs.
BST wheels have always been popular at the ‘top end’ of the Harley custom market and with performance custom builders (and Sportster and Buell racers). Having migrated from the drag strip, where the combination of strength and light weight are the primary characteristics of a carbon fiber wheel, they are increasingly no longer just the preserve of the strip and circuit.
|Terry Annecke, Operations and Marketing Director, at EICMA in 2017|
In drag racing they have been popular for the reduced mass they represent when starting a run (the stationary bike responds sooner and faster to the rider’s reaction time) and for the improved speed (and reduced time) that the bike then carries to the finish line. On the race circuit lighter weight not only means higher speed, but greatly improved cornering and faster acceleration out of the bend.
For street use they have generally been regarded as being the province of the ‘exotics’ - the top end custom jobs and show bikes where money is no (or relatively little) object.
Increasingly though, and especially where the objective is performance and the improved handling that comes with lighter weight, carbon fiber wheels are finding their way onto more street bike make-overs. Though still in relatively small numbers, as the custom scene continues to morph and incorporate influences from elsewhere in the motorcycle market (not least sport bikes and sport tourers), the market for carbon fiber wheels on street Harleys and genuinely streetable customs (of all platforms) has grown, and shows every sign of continuing to do so in the decade ahead.
Located in Johannesburg, South Africa, BST was founded by former racer Gary Turner and business partner Terry Annecke in 2002 - the company celebrated its 15th anniversary last year - and now has more than 25,000 wheels in the market worldwide.
The company employs some 50 people at their 51,500 sq ft (4,800 sq m) facility and has exported their wheels “to just about everywhere in the world, even including Kazakhstan! Basically, everywhere that has a motorcycle community.”
BST almost single-handedly created the market for volume produced carbon wheels, and as such has had quite an influence on the race and custom motorcycle industries.
However, ‘caveat emptor’ - buyer beware - not all carbon fiber wheels are created equal. BST is one of the very few manufacturers in the world (a handful at best) whose products have been proven on the drag strip, the race circuit, and even the “Great White Dyno” that is the wheel-hostile environment of the legendary Bonneville Salt Flats.
Like all the best products and manufacturers, R&D and testing are at the heart of the process. “A traditional metal wheel manufacturer uses one wheel per test, but our wheels are engineered to withstand four tests - cornering fatigue, radial fatigue, torsional fatigue and impact testing - all using the same one wheel,” Gary explained.
The company has been ISO 9001 certified since 2003, audited by the German TÜV, the JWL in Japan and the DOT in the United States (BST wheels are DOT E certified). When I met him at EICMA (the ‘Milan Show’) last year, Gary told me that as far as he is aware, his company is the only OEM certified supplier of carbon fiber wheels in the world, and by far the largest aftermarket supplier with four different styles of wheels in sizes ranging from 12” to 23” and over 200 individual fitments for 20 different manufacturers.
One of the common questions about using carbon fiber wheels concerns the effects of UltraViolet light. The testing and certification processes that BST wheels have been through, such as that with the German TÜV authorities, includes both salt spray and UV degradation testing, and the result of that testing was that BST wheels show no noticeable degradation in connection with either.
|The limited-edition 1200cc 200bhp V4 Norton VRSS/RR|
Applications for BST’s ‘Black Star’ 5-spoke wheels range from selected Harley Touring models through Twin Cam Softails and Dynas to V-Rods and Sportsters. Recent OEM contracts include the (initially) limited-edition 1200 cc, 200 bhp V4 Norton VRSS/RR (BST also produced the V4’s carbon fiber fuel tank, which has been reinforced with Kevlar and chemically treated to safely hold gasoline) and the even more limited-edition Ariel ACE R.
The wheel of choice for Confederate and Ecosse cruisers, BST also has a long standing “wheels and more” relationship with American V4 Sport-Tourer manufacturer Motus, was the wheel chosen by San Francisco based E-Bike start-up Alta Motors for its Redshift ST Street Tracker concept, and will be the stock wheel on the production version. Most recently Gard Hollinger and Keanu Reeves chose BST wheels for the 2018 Arch Motorcycles S&S Cycle engined KRGT-1 update and the new Method 143 and Arch 1s.
Another of BST’s most recent successes has been with Ducati’s new 1299 Superleggera, said to be the first ever factory bike to be equipped with carbon fiber wheels as stock. Gary says Ducati chose carbon fiber “to lighten the load and provide a reduction in rolling resistance” and settled on BST as their carbon wheel of choice “over all other manufacturers, including some on their own doorstep in Italy and elsewhere in Europe.”
BST wheels have not only become a default choice for Harley, Buell and performance V-twin customizers looking to save weight, add strength and improve handling, but for years have been the ‘go to’ for customizers for whom performance engineering has been the driving force in their design decisions at the AMD World Championship of Custom Bike Building.
They are made using pre-preg carbon fiber - "pre-impregnated" composite fibers where a thermoset polymer matrix material, such as epoxy, is already present. The fibers often take the form of a weave and the matrix is used to bond them together and to other components during manufacture. The thermoset matrix is only partially cured to allow easy handling; this B-Stage material requires cold storage to prevent complete curing. B-Stage pre-preg is always stored in cooled areas since heat accelerates complete polymerization. Hence, composite structures built of pre-pregs will mostly require an oven or autoclave to cure.
Pre-preg allows the wheel to be worked on a flat surface, in an industrial process, and then the impregnated fibers are formed to shape later - not something that can be done as well using the alternate hot injection process. Pre-preg also allows impregnation with a bulk amount of fiber and then store it in a cooled area (below 20°C) for an extended period of time for curing later.
BST makes 5 and 7 spoke designs in aerospace FAR25 qualified materials (as also supplied to Airbus, Boeing, Ferrari and McLaren among others), providing complete aerospace critical standard traceability during manufacturing processes. All wheels are coded and serial-numbered for easy identification. Using fully automatic aerospace nesting and cutting machines, each wheel's pattern is cut and part-numbered simultaneously, guaranteeing correctness and uniformity.
Far stronger than standard wheels, BST wheels are comfortably over-engineered for road use and they pass all known tests for their rims, corner, radial and torsional fatigue and impact test standards.
Carbon wheels deliver at least a 50 percent weight saving over alloy wheels and centralize the weight due to the lighter rim, resulting in improved performance and handling. The smaller radius of gyration completely changes the acceleration and braking characteristics. Acceleration is improved and braking is much easier, with improved stopping distances as well, “improvements that are real and noticed by everybody who rides with our wheels,” says Gary.
|Arch ‘Method 143’|
“The steering is nimbler too, with the bike changing direction a lot more easily, and because of the lower un-sprung mass, the tire does less rebound work and the springs and shocks work sooner - so whereas going over something like a one-inch expansion joint was a jolt, the bike does not now feel it as much. Quite remarkable to feel and a very noticeable difference.”
The end result, according to Gary, is the “strongest, lightest and most durable wheels available, enormous performance and handling benefits, extended tire life, and improved acceleration, deceleration and braking performance. The bike will handle more easily with much faster turning into corners with absolutely no suspension modifications or adjustments whatsoever required.
BST wheels are painted with an automotive grade clear coat (with UV protection) and finish options include matt black, high gloss, satin and even chrome look.