Cycle News - Archive Issues - 1990's

seat, 41mm Kayaba forks from a TZ250 and an Ohlins rear shock, the Pami weighs in at a remark~ble 246 pounds dry or 253 with oil and water - coincidentally right on the FIM's arbitrary weight limit for the new European supermono series at World Superbike rounds this season. Tigcraft boss Dave Pearce moved the engine 20mm forward in the chassis before the '95 season, and, as a result, the Pami has an extreme frontward weight bias of 56.5/43.5 percent. In additition to the engine location, these weight bias numbers are also helped by the meaty 320mm cast-iron brembo front discs and skinny 190mm rear. Wheelbase is 52.75 inches, but as I found when name to test the bike at Zeltweg, ·it doesn't feel too compact, thanks to the extremely rabonal riding position Dave Pearce dials into his frames. Unlike some chassis designers, he loads up the front wheel at the design stage, statically, rather than using the rider's weight to do the job, which is usually at the expense of comfort and controllabiUty. So the Pami is a bike with radical steering geometry that helps you do the business without making you think it was hard work doing so. I trunk the tean is "user-friendly." Put a chassis that's this rewarding to ride together with a motor that's as fast and torquey as the Pa;mi's and the result is a bike that sets new standards for its class. A true champion. I've ridden just about every major 50S contender from around the world in recent years, but I have to say the Pami is the only Supermono I've ever sampled that I'd be happy to race instead of my Ducati. That's really saying sometlUng, because while the Italian bike isn't the fastest or the lightest, or the most powerful or most torquey single-cylinder racer of the modem era, it is the best package, the best all-rounder. Or so I thought until I rode the Pami. You want proof? Okay. Check out the lap times. I hold the Supermono lap record for the fast, swoopy Zeltweg track on the Ducati at 2 minutes, 1.91 seconds, set in the support race at the '94 World Superbike round in vain pursuit of Tommy Komer and Maurice Bolwerk on their Rotaxes. In 10 laps aboard the Pami in a crowded open practice session on the same track - with pretty heavy traffic -1 broke my own lap record by 0.2 second on a bike set up exactly as Herbert Enzinger raced it. There were no suspension changes at all to suit my higher comer speeds and. heavier use of the front tire, comapared to Enzinger's more Superbike-derived, point-andsquirt style which uses the rear tire more. I'm sure the two-minute barrier would have been a goner if we'd had more time to play with setup and a more open track. But sadly it was right at the end of the day, and the sun was setting, putting an end to playtime. "'ut if Michels and his cooperatives ever need a spare rider, they know where to look. The great thing about the Pami is the confidence it gi ves you. It feels like a really solid, together racer that has obviously been carefully honed and painstakingly refined. The engine doesn't betray any hint of its roadster origins, revving smoothly to the 9200rpm appointment with the rev limiter, without any more significant vibration than the higher-revving Ducati, the paragon of smoothness among swift singles. Compared to a Yamaha or even a Rotax, the Pami's BMW motor is smoother and less tiring, and there's no comparison with th.e similarly vibrating engine in long-stroke Bimota guise though the reason for that, says Dave Pami·BMW Specifications Liquid-cooled. DOHC. four-valve. dry-sump, single--eylinder four-stroke with single gear-driven balance shaft and chain camshaft drive Bore x Stroke . . .. . . .. .. .. .. .. . .. .105 x BOmm Displacement 694cc Compression ratio ~ _11 .5: 1 Carburetion (2) 36mm M!kun! RS flat-slide Ignition Pam! digital programmable CDI Transmission ' Close-ratio five speed Clutch . , Multiplate wet Chassis Aluminum twin-spar incorporating oil tank in steering head Engine Suspension Front .41 mm Kayaba inverted telescopic forks Rear. . . . . . . . . . . . . . . . . .. Fabricated aluminum swingarm with single Ohlins shock and rising-rate linkage . 24°/90mm 52.75 in. 253 Ibs. 56.5/43.5% Rake/trail Wheelbase. . . ...... . Weight .......... . Weight distribution, front/rear Brakes Front Dual 320mm Brembo Rear (Top) Dual 34mm Mlkunlflat·slides are bolted to the custom-made, machined-from-solid, four-valve cylinder head. (Above) The fabricated aluminum swingarm Is connected to the shock by a Pemi-deslgned linkage. Corner-exlt traction Is excellent. (Below) The three-liter 011 resevolr for the dry-sump engine Is incorporated into the steering head of the Tlgcraft-bullt aluminum frame. Pearce, is that Bimota doesn't use a front engine mount, whereas Tigcraft does and that makes all the difference. However, there isn't the need to rev the Pami that high, because the shortstroke motor comes on strong at 5000 rpm, then picks up engine speed very quickly for a four-stroke single, delivering vivid acceleration up to the 8600rpm power peak. At that point you're reminded to change gears by a large flashing light - an idea from the car world brought to motorcycles by John Britten and since copied by Aprilia and Honda on their GP bikes - mounted to the left of the old-style Krober tachometer. This is a neat idea for a four-stroke single, too, because it helps you max out the engine output by changing up wide open at exactly the optimum moment· via the Pami'~ excellent speed-shifter. On a bike like this, every horsepower counts. The whole shifting package works particularly well accelerating through long, fast sweepers such as the ones that abound at Zeltweg, like the the "wall of death" before the finish line where you brake hard downhill into the turn, then get hard on the gas cranked well over, shifting up two gears as you max out your exit speed, waiting for the light to stop flashing in the corner of your eye before you hit the race-pattern shifter to grab the next gear, wide open. Magic. However, while upward shifts like these are fine on the Pami, changing down in the close-ratio gearbox is more problematic, and both first and second gear could be taller to close the ratios up cast-iron floating discs with four-piston Brembo calipers Single 190mm Brembo fixed steel disc with two-piston Brembo caliper Tires/wheels Front 125/600-17 Bridgestone radial on 3.50-in. Dymag wheel Rear 165/620-17 Bridgestone radial on 5.25-in. Marchesini Top speed.... . .. 149 mph CZeltweg) Year of construction 1994 Owner Team Paml, Trier, Germany still further. I missed the shift from third to second five times in 10 laps. And you only use second twice per lap, at the chicane and the second left coming down the hill. I can't recommend taking either of these in neutral with your pulse rate boogying to a salsa bea t. Obviously a selection problem - but downshifts at their best were rather heavy and imprecise. This is the only real criticism 1had about the mechanical package apart from the rather harsh throttle action caused by a combination of the usual sudden response of the flatslides and fitting a stiff return spring for quicker action. The action is quicker, but the quickness comes at. the expense of precision. It's worth noting that the Pami runs pretty cool, thanks to the modified Suzuki RGV250 radiator which kept the BMW motor at just under 170 degrees on a 95-degree day. Bimota needs to source this for the Supermono Corsa badly. . Though it wasn't set up for my riding style or weight, it was hard to fault the handling of the Pami's Tigcraft chassis, which with a similar degree of forward weight bias to La Ducatina felt very similar to my own Superrnono, especially with the same Bridgestone rubber fitted. As in 125 and 250cc Grand Prix racing, 50S racing success is largely based on high comer speed. Thanks to the front weight bias and the terrific front tire the best customer rubber available for this kind of bike because Bridgestone's main slick tire development is for the 125 and 250cc Grand Prix classes - you (Above) The single-cylinder Rotax engine comes out of BMW's F650 Funduro dual sport bike, but a custom, programmable electronic ignition and a host of other changes boost output to 85 bhp at the crankshllft. can really keep your momentum up in turns. You need to take a lot of care setting the front suspension up right for this, though, and Pami has done that - the downhill off-camber sweeper after the Boschkurve proved that. Its race-earproduced ripples are a stem test of any front suspension, and the budget TZ forks in the Pami coped really well, with just the right amount of extra compression damping to keep the wheel from chattering as it eats up the bumps. The rear Ohlins worked ~Il, too, though it could have done with some more preload to keep the rear end from squatting under my extra weight. Set as it was, there was some understeer hard on the gas out of turns, but on such a light bike it was easy to correct with a little muscle. The shock's progressive response via the well-sorted Tigcraft linkage delivered excellent traction out of the chicane, where T could get hard on the gas so much earlier than the bigger, more powerful BEARS racers I was practicing with - just as Mike Edwards did to me at Thruxton. Now I know how and why! I wonder if Gottfried Michels and his gang would like to start waving their wands over a Ducati Supermono instead - or maybe the new desmo MuZ? (N 27

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