Factiva

LP 

We propose a low-dimensional model of the three-way catalytic converter (TWC) that would be appropriate for real-time fueling control and TWC diagnostics in automotive applications.

The model reduction is achieved by approximating the transverse gradients using multiple concentration modes and the concepts of internal and external mass transfer coefficients, spatial averaging over the axial length and simplified chemistry by lumping the oxidants and the reductants.

TD 

The reduced order model consists of seven ordinary differential equations and captures the essential features of a TWC providing estimates of the oxidant and reductant emissions, fractional oxidation state (FOS) and total oxygen storage capacity (TOSC).

The model performance is tested and validated using data on actual vehicle emissions resulting in good agreement for both green and aged catalysts including cold-start performance.

We also propose a simple catalyst aging model that can be used to update the oxygen storage capacity in real time so as to capture the change in the kinetic parameters with aging.

Catalyst aging is accounted via the update of a single scalar parameter in the model.

The computational efficiency and the ability of the model to predict FOS and TOSC make it a novel tool for real-time fueling control to minimize emissions and diagnostics of catalyst aging. (c) 2012 Elsevier Ltd.

All rights reserved.

3 diagrams, spectra, and 7 tables

LP 

After sitting in the garage all winter, my bike doesn't run quite as cool as I remember. Embarrassing as it is to admit, I can't remember the last time anything below the radiator cap got any love in. the garage. There's coolant in there, but it's probably pretty old. What's the best thing to do now that the weather is turning and starting to warm up?

TD 

Job one is to replace what's in there with fresh stuff. The typical 50/50 mix of distilled water and coolant turns acidic enough to corrode engine internals over time. Additives meant to prevent rust and lubricate your water pump also deteriorate. Make sure the engine is cool. If what comes out is closer to brown than green, flush the radiator to remove sediments. And handle that stuff with care: Ethylene glycol is toxic and must be properly disposed of. Unless you're going with a ready-to-use product like Pro Honda HP or Maxima Cool-Aide, mix distilled water and coolant ahead of time. Since water is the superior heat-disposal medium, don't use more than 60 percent coolant.

LP 

Honda's CB750 Four changed the world at the 15th Tokyo Motor Show in 1968, rendering anything less effectively obsolete with 68 horsepower at 8500 rpm and a top speed around 125 mph. Purists and collectors know this pristine 1969 CB750K0 by its Candy Blue Green paint, louvered side covers, each 28mm Keihin carburetor cued by a separate throttle cable, howling 4-into-4 exhaust system and that extra flourish on the seat. Officially released in the U.S. on June 6,1969, the KO (say "kay-zero") was faster than all of its predecessors. Sand-cast engine cases on the first 7414 examples make original survivors as rare as they are expensive.

TD 

Subsequent models aren't quite as fast or nearly as collectable, but for anyone more interested in actual riding than escalating auction values, one of the 500,000 single-cam CB750s built between '70 and '78 is a better bet. The pipe-rack frame and swingarm are predictably flexible, suspension is primitive and it takes a serious squeeze to get that single front disc brake's attention. But dial back your expectations three or four decades and any well-preserved CB750 is a certified hoot to ride.

Aside from weeping a bit of oil around the head gasket, Honda's 736cc drysump inline-four ages more gracefully than other classics. It can go 100,000 miles or more between major rebuilds, given valve adjustments every 3000 miles and oil changes every 1500. Expect a bit of rattle from the clutch and other internals when cold. Once warm, evil sounds from the bottom end are bad news. Replacement parts are largely interchangeable and thus readily available for mid-'70s models. So is a beat-up, rusty exhaust. Genuine replacements--especially the howling pre-'72 4-into-4 system (Honda Model Code 300)--are insanely expensive. According to Kurt Winter at Valley Cycles in Chatsworth, California and founder of the CB750 Preservation Society (www.cb750.org[http://www.cb750.org]), the bikes have proven recession-proof, but prices vary dramatically by zip code. Value and performance taper off after '69. The popularity of cafe-racer conversions has driven prices up, but bargains exist. Revive a '70s original or roll some revisionist history of your own, the CB750 is still one for the ages.

CHEERS

Smooth, abundant power plus legendary longevity and timeless lines,

JEERS

Archaic brakes, chassis and suspension, cold-blooded in the a.m.

WATCH FOR

Smoky exhaust, sticky front brake caliper, weak charging system, broken spokes.

VERDICT

Still the modern classic after all these years.

VALUE

1969 | $22,000

(sand-cast cases)

1970 | $9500

LP 

How many bikes is too many? Contributor John L. Stein draws the line at 23, which meant bike number 24, a dilapidated 1981 Kawasaki AR50, needed a new home. The addition of the AR brings Ari Henning's collection of 50cc two-stroke streetbikes to three--three too many, according to his neighbors and the California Air Resources Board. The scrawny Kawasaki will undergo a comprehensive rebuild and be painted period-correct lime green before entering service as an errand-runner and way-cool pitbike.

LP 

Moto Guzzi was a major player in the early days of Grand Prix mmmm roadracing. The Italian firm won the 250cc World Championship in 1949. 51 and '52, and five consecutive 350cc titles from '53-'57. Guzzi's horizontal-singles were less successful in the premier 500cc class, however, where they were consistently outgunned by Gilera, then MV Agusta inline-fours. In late '54, hoping to close this gap, legendary Guzzi engineer Giulio Cesare Carcano created one of the most daring machines in motorcycle history: the Otto Cilindri V8.

TD 

Why leap from one cylinder to eight? Carcano saw no advantage in building another inline-four that would, at best, be only incrementally better than the rest. An inline-six could make more power, but would be too wide. A pair of 250cc inline-fours arranged in a 90-degree Vee, on the other hand, could be narrower than a 500cc four and, with increased valve area and a higher rev ceiling, produce even greater horsepower. In the unique racing calculus of power, packaging and weight, the V8 made perfect sense.

Carcano's liquid-cooled, DOHC VS was a masterpiece of miniaturization. With 16 delicate valves, eight tiny pistons, eight individual 20mm DeU'Qrto carburetors, eight separate coils, eight threadlike exhausts and eight contact-breaker points, the V8 was fantastically complex. And the math added up: Oversquare (44.0 x 40.5mm) engine geometry delivered 78 horsepower at a stratospheric 12,000 rpm--a 10-horsepower advantage over the rival fours.

The Otto Cilindri was remarkably compact. Its pale-green dustbin fairing was just 30mm wider than Guzzi's 350cc single, and a 330-lb. racing weight gave a better power-to-weight ratio than any GP racer built to date. It was ferociously fast, but ill-handling and fragile. Aussie rider Ken Kavanagh debuted the V8 at the 1955 Belgian GP and dropped out with a broken crank. The V8 raced twice more that year--at Senigallia and Monza--and DNFed both times.

The V8 didn't finish a single race in '56, either. Kavanagh led Imola's Coppa d'Oro (Gold Cup) until the water pump broke. Two-time 350cc World Champion Bill. Lomas set the. fastest lap at the Dutch GP and then promptly broke, while Kavanagh crashed out. Lomas qualified on pole at the Belgian GP only to suffer ignition problems during the race. Meanwhile, Kavanagh was so terrified by the handling on Spa's long curves that he never raced the V8 again.

A total engine redesign improved reliability for '57, with encouraging results. Giuseppe Colnago won an Italian Championship round at Siracusa, Sicily--the V8's first win--then Dickie Dale won the Coppa d'Oro, but Dale's fourth-place finish in the Isle of Man Senior TT was the best Grand Prix result. Clocked at 178 mph on Spa's Masta Straight--a speed that remained unmatched for 20 years--the V8 was indisputably fast. But development stopped when Guzzi withdrew from GP racing at the end of '57, preventing the world from witnessing the V8's true potential.

So ended one of the finest chapters of motorcycle racing history, in which Moto Guzzi won a remarkable 3329 races, 11 Isle of Man TTs and 14 world titles. The firm went on to enjoy sporadic success in other series, but never competed in the Grands Prix again. The V8 never returned to competition. Only five were ever built, and just two originals remain, both displayed at the Moto Guzzi factory museum in Mandello del Lario.

Moto Guzzi began building singles and today sells twins exclusively, but has raced every possible engine configuration in the past. None were as fantastic as the Otto Cilindri V8, ridden here by Keith Campbell in 1957.

LP 

* Central Pennsylvania's Anthracite Outdoor Adventure Area (AOAA) recently received a grant of $1.5 million from the state for construction of off-highway vehicle facilities, 200 miles of trails, trail-head amenities, parking, utilities, ADA access, and landscaping. Jeep Jamboree USA has already made plans to hold an event there in August.

TD 

* SEMA tells us the Off-Road Business Association (ORBA) has been exploring options for the protection of the Off-Highway Motor Vehicle Recreation (OHMVR) trust since July 2011, along with its strategic partners AMA District 36, AMA District 37, the American Sand Association, and the California Association of 4 Wheel Drive Clubs through the use of its registered state lobbyist, Aaron Reed and Associates. The OHMVR, established to provide accessibility to off-highway recreation and provide a variety of services and benefits to California residents and visitors, operates on an $85 million yearly budget that comes primarily from gas taxes and the sale of Green Stickers. The state borrowed $10 million in gas taxes from the budget before it reached the OHMVR trust earlier this year, according to Fred Wiley of ORBA, and the removal of the funds will continue indefinitely.