Honda Cb750f

HONDA CB750F

One year after Honda replaced its classic 750 Four with the new CB750 models, the company has made several not-too-apparent but significant changes for the 1980 model year. Because the 1979 model Honda 750s sold out earlier than expected, and because the changes to the 750s have been minor, the 1980 model Honda 750s, both the F and K, are being released earlier than the really new 1980 model Hondas.

How can the 1980 Hondas be distinguished from the 1979 models? The 1980 750F is most obviously different because of its black reversed Comstar wheels. The 1980 750K doesn’t have the same CX500-styled taillight found on the 1979 model K. Then there’s the speedometer. In accordance with federal law. the 1980 Hondas, and all 1980 vehicles, have speedometers reading no higher than 85 mph. Right at the 85 mph position there’s a pin mounted on the face of the speedometer that keeps the needle from running any farther. No. it doesn't hurt the speedometer if the motorcycle’s speed is greater than 85 mph. The connection between the needle and the incoming revolutions of the speedometer cable is magnetic so when the needle stops and the acceleration continues. nothing gets bent. Yes. 1979 model speedometers are interchangeable w ith the 1980 bike, although the cost is steep, we're told. For the rider who just has to know' how fast he’s going there’s the tachometer, its figures being easilv translated to miles per hour with a little simple arithmetic.

What makes fast riding inviting are the improvements to the frame and suspension. The 1979 750F was a fine handling bike with excellent cornering clearance and frame geometry but it suffered from shocks that faded quickly when run hard. The tires were slippery and the plasticswing arm pivot led a short life. It was a tremendous bike handicapped by a tew

Improved Suspension Makes Honda’s Sporting 750 Even Better.

weak links.

For 1979 the shocks have been changed to an all-new adjustable damping type. Unlike the adjustable damping shocks on Suzuki’s biggest machines, the Honda shocks have separate adjustments for compression and rebound damping, plus the internal relief valves yield different damping rates depending on the speed of piston movement.

Rebound damping is adjustable to one of three degrees by turning a collar at the top of the shock body. The collar is connected to an adjuster pipe that turns a

a perforated plate through a claw. The perforated plate has different size holes, larger holes allowing shock fluid to move faster and providing correspondingly less damping effect. As the plate turns inside the shock, different groups of holes are uncovered. yielding the different damping rates. Some of the holes are covered by a blow-off spring which serves as a relief valve. When the shock piston travels at normal speeds, the fluid runs through the normal holes. When a big dip forces the piston to move faster, building up more pressure, the blow-off'spring uncovers additional holes and allows less damping

a effort.

Compression damping is adjustable to one of two positions by flipping a lever at the bottom of the shock body. Again, the collar ends up twisting a perforated plate with different size holes providing different damping rates and a blow-off spring reducing the damping when big bumps or a series of bumps builds up shock fluid pressure.

Combined with the new shocks are new needle bearings for the swing arm pivot, replacing the plastic bushings used on the first tw in cam 750s. The frame area around the swing arm pivot has been beefed w ith additional gusseting and the triple clamps provide an additional 5mm offset which translates into an additional 4.33mm wheelbase and trail. Finishing up the handling improvements are a better grade of tubeless tires mounted on the reversed Comstar wheels of the 750F or the wire spoke wheels of the CB750K. An unusual change to the new model is the 530 o-ring chain used in place of the 630 o-ring chain of last year’s model. Honda says new chain technology makes the 530 chain longer lasting and quieter than the 630 chain used previously.

The changes on the 1980 750 are minor. The engine is unchanged. It’s still the same dual overhead cam, 16-valve Four with accelerator pump-assisted CV carbs and inductive electronic ignition. It was a stateof-the-art motor last year, and because last year’s model met the stiffer 1980 emission regulations, the 1980 bike is exactly the same and Honda didn't have to go through another emissions test this year.

Take the most powerful 750 motorcycle made, improve the suspension and put it in a rigid frame and the result is the most sporting machine on two wheels. It has the power to turn quarter mile times of 12.52 sec. at speeds of 107.27 mph. The 75 bhp motor can propel the 750F at speeds of 125 mph. At the same time the Honda is a match for any machine on a winding road. It corners confidently and precisely, needing little effort to steer, having no wobble, and able to lean over farther than anyone would imagine a transverse four cylinder engine bike could.

Changes in the way brake discs are machined have eliminated a pulsing felt through the handlebar of 1979 model Hondas with discs, the new brakes working smoothly, powerfully and predictably.

Riding the CB750F is a treat even for people who spend every day riding every possible brand of motorcycle. Even the 85 mph speedometer, which will be found on all new motorcycles, can’t dampen the thrill of riding such a responsive motorcycle.