Cycle News is a weekly magazine that covers all aspects of motorcycling including Supercross, Motocross and MotoGP as well as new motorcycles
Issue link: https://magazine.cyclenews.com/i/125864
By John Overton The term "dual purpose" IS an outdated advertising slogan as far as the 250 KTMfPenton goes. There are Pentons competing In every type o f motorcycle event imaginab le. The same model, with few changes other than those for personal preferences, blasted class 24 number one desert racer Mark Aden t to three successive overall wins in the Mojave. It powered Buck Murphy to second 250 Expert at the Daytona motocross and carried Carl Cranke to first overall at the Shamrocks' and Ft. Hood ISDT Qualifiers. There's even a guy in Florida road racing a Pen ton . . . and winning. WinninJ( an y thing and everything that's a motorcycle event is what Penton is all about. ' These bikes are manufactured in Austria from high quality components and materials. A quick walk-around reveals things like Akront rims, Metzeler tires. Ceriani forks, Girling shocks, VDO speedometer, Bing carburetor, Motoplat ignition, Chrome-moly frame. fiberglass tank and magnesium hubs and engine cases. At ten tion to detail is apparen t, with a profusion of Nyloc aircraft nuts, a fork slider boot with molded-in brake cable rou t er , and a gas cap co nnected to the tank by a chain so it will never fall in the dirt o r get lost. entered two National I Championship endures: the Red Garter in Southern California and the 49'er in Northern California. Between the two events, we encountered a lot of difficult and extremely varied terrain (nar ro w trails; loose, rocky hills; deep water c r o s s i n gs: d usty fire roads; lush mountain meadows: slick, wood -strewn logging areas; oozing mud; high-speed asphalt; choppy sandwashes}. The Penton 250 handled every situation wi th relative ease, never struggling and, in fact, b reezing through even the cobbiest terrain in smooth fashion . We should mention that some changes are req ui red before the Penton can perform up to its capabilities. T he Girling shocks on earlier models are given a well-aimed toss at the nearest garbage can . With a 160 pound rider aboard. only an inch of poorly damped travel remains and this quickly disappears once under way. The result is a terrible "pogo" action wi th the en tire bike jarring and rocking baclly. New KONI 80s come standard on current model PentonfKTM 250s and are available as a trade-in item for all 250 owners - at c ost. An indication of the excellent handling lurking in the Penton frame and geometry is the fact that the rear end never hopped from side to side, no matter how treacherous the ground being traversed. Once a set of KONIs was installed, that hidden handling appeared. Never again did the Penton kick up its ass end. The good damping units should still be standard on a bike of this caliber. and now, they are. Another acutely needed change involves the forks . While th e damping and progressive action of the Cerianis are good, they are sprung very softly. A one-inch spacer preloads the springs enough fo r enduro riding, but may be necessary for desert work, A one-inch (or so) piece of Husky fork spring works well. If you weigh 135 pounds they'll probably work splendidly as is. Actually, 1 prefer to see forks arrive sprung too softly rather than too hard. Spacers are simple and easy to cut, but how do you soften up a stiff spring? On ce these ch an ges are made the Hare Scrambler be comes one of the finest handlers available - completely neutral and willingly responsive. The Penton is a very precise bike, enabling even the average rider to pi ck any line and hold it. On fire roads we could hang the rear out with power on and slide corners in complete control. A long wheelbase and plenty of fork lock makes sliding-out very unlikely. With power off, the Penton still slides beautifully, never hinting at a high-side, The same large turning angle of the forks that makes sliding so much fun allows tight, low -speed turns to be made in surprisingly small areas. This versatility in hand ling is wha t he lps the Pen ton to win one week in the desert. and the next week at an enduro. When taking jumps at speed, the front naturally assumes a h igh attit ude. By shifting rider weight forward the front can be kept down, or brought to any attitude and height the rider wishes. This sort of neutrality on the bike's part complements its versatility. Handling like this requires more involvement from the rider. No effort, just involvement. The rider tells the bike what to do through throttle and body movements and the bike responds. The Penton demands a confident. aggressive style, and responds accordingly. Besides excellent handling. the versatility inherent in the Penton 250 demands a flexible, powerful engine. Power is something the Penton produces throughou t a wide RPM range. While you ca n feel the engine come on the pipe rather strongly, so in that sense it is slightly peaky, there is so much power present outside the powerband that the engine remains a willing puller from low RPM. Couple this ability to pull strongly from down low with peak horsepower equal to that of faster stock motocrossers and, again, the result is amazing versatility and almost universal appeal. The construction and design of this wonder engine from KTM is really fascinating. As previously men tion ed , the cases and side covers are all magnesium, resulting in an extremely lightweight engine package, ligh ter , in fact, than the Pen tonfKTM 175 motor. The cylinder barrel is alloy with a pressed -in liner and massive finning. Rather elaborate po rting consists of the usual intake and exhaust ports, plus four transfers and two boosters. The boost ports, placed in the rear of the cy linder, breathe through a horizontal slot in the back of the cast aluminum piston. Fuel is dutifully mixed by a 36mm Bing carb o The Bing meters the premix smoothly and precisely, allowing good throttle control and even response. It allows the luxury of an idle and even permits the engine to con tin ue to run with the bike lying on its side. If the engine dies, though, while on its side. it will load-up. This was the only occasion during the two endures 1 could make the Penton even hint at four-stroking. Even when loaded-up afte r a get-off', three kicks with the throttle wid e open had it runn ing cleanly agai n , 1 was never forced to reac h for the wrench and a fresh spark plug, A s i x -sp e e d transmiss ion wid beautifully spaced cogs and impeccable manners guarantees full command of all the engine's power. With the exception of first-to-second-to-first, which requires a ' d e l ibera te shift, all shifts are "snick-snick" with or without ' the clutch. First gear is super low and allows plonking along at a walking pace while sixth is for fire roads and very fast desert racers. Top speed is around 80 MPH . The clutch itself. though. must be in close to perfect adjustment or it slips. It may be the one chronic weakness of the machine. We found the Penton to be completely wa terproof without modification. During the 49'er, we crossed streams where water washed completely over the engine, muffling its sound and the exhaust 'pip e was totally submerged. The engine never missed a beat and we powered off while other riders cursed and started pulling spark plugs, This refusal to be affected by moisture can be attributed to the well-sealed, pointless Motoplat ignition, and the under-tank air intake. As on all new Pen tons, portholes high in th fra me backbone pick up air and duct it thro ugh the frame to the air cleaner and still-air chamber, w hic h are accessed thro ugh adequate ly tight re movable sid panel. Alo ng with deep water, we p ut th Penton into mud over the hubs, an naturally the shouldered Akront. retained abouj 10 pounds o f it Shoulderless rims would seem more appropriate on a machine of this caliber and ce r t a i n l y would be greatly preferred. A set of good, spring-loaded serrated foot pegs would be appreciated also. The standard items are slipper) and made from lightweight metal. The) bend easily in a fall. Worse still, the peg