1984 Honda Nighthawk 700S

One of my all time favorites for style and design. The following information is from Wikipedia."Honda marketed the CB700SC (also called Nighthawk 700S) in the US from 1984–1986, configuring the bike's specification to avoid a 1983 US tariff on motorcycles over 700 cc.  Honda marketed the CB750SC, a virtually identical bike with a slightly larger engine capacity, outside the US. A very closely related cousin was chain driven, sold in Europe, Australia and Brazil. It continued in production in Brazil for many years.


Similar to the previously introduced 650 Nighthawk, the Nighthawk S featured a 700 cc engine, shaft drive and hydraulic lifters in a bike with angular lines, a small "bikini" fairing and a 16 inch front wheel more typical of a sport bike. The Nighthawk 700S originally (1984–1985) featured black paint with either red or blue blue accent panels. In 1986 the 700SC featured navy blue paint (with white panels and red pinstripes) or black (with red panels and tri color red pinstripes).[2] Valve cover and clutch covers were painted black as well as the wheels.

The engine was the same layout as the 650 Nighthawk's, but a completely different design and shared no parts. It had double-overhead cam, four cylinder with hydraulic lifters which virtually eliminated valve adjustments. The exhaust was a four-into-two finished in black chrome. The engine was enameled mostly in black with brushed satin silver trim. Other components were also enameled in black including the lower fork legs, handlebars, and rear grab rails."

These bikes have quite a following, check out this link for much more information.

Ride safe, ride often --  JF

Motorcycles of the 60s

The video was taken at the Seattle International Motorcycle Show. Bikes on display were either in the VME (Vintage Motorcycle Enthusiast's) section, or part of the Sound Rider display. Enjoy!

1985 BMW K100RS

Featured today is a 1985 BMW K100RS. Nick named the flying brick, due to the flat four motor laying horizontal in the frame. Produced between 1983 and 1992, the K100RS is legendary for its longevity...many examples with 100,000 to 300,000 miles. Perhaps the only nit pick with the K bike, some thought it was boring to ride, due in large part to how smooth the motor was.  I don't share that opinion. Rated at 90hp, fuel injected, 983cc and weighing in at 548lbs. Perhaps the greatest challenge to owning one....finding a low mileage bike for purchase. Ride soon, ride often....JF

Yamaha YICS-Good for fuel economy

Have you ever wondered what YICS is? Why is it blazoned into the covers on the engine of your older Yamaha motorcycles? Is it like Wonder Bread? Does it make your bike run farther, jump higher, and outrun the bad guys? Yamaha introduced Yamaha Induction Control System in 1979 as a fuel-saving engine system in 4-stroke motors. As stated in an earlier post, some of the most fuel efficient motorcycles were of the late 70s and 80s. How does it work? The following is a summary of the system from a Yamaha service manual.  "The YICS  consists of 2 separate chambers, each connected, by a hose, to a port on each cylinder just behind the intake valve.  As the piston moves down on the intake stroke, the cylinder fills with a fresh air/fuel charge.  A vacuum is created in the YICS chamber at the same time.  When the intake valve closes, part of the charge is drawn into the YICS.  When the intake valve reopens the mixture in the YICS shoots back out through an angled tube into the cylinder, mixing with and swirling the main intake charge.  The swirling charge is then compressed and ignited, burning more completely and producing more power than that of a conventional engine."
With this in mind, also note that many owners of XJ bikes recommend using high octane fuel, or a good fuel cleaner to keep the YICS tubes from getting clogged. I recommend using a product called FP60 by www.LCDINC.com  On their website the following benefits are claimed for their fuel additive:

• Antioxidant and solvent properties scavenge water and moisture from the oil and fuel systems
• Emulsifies carbon and varnish and most other "gunk"
• Stabilizes the fuel, allowing more efficient burn in the combustion chamber
• Lowers fuel mixture freezing points
• Reduces carbon dioxide and NOX emissions up to 30%
• Leaves a thin, protective coat of oil over vital fuel system parts, including fuel pump, gas tank and fuel injectors.

I've been using FP60 for four years and have had great success with it. Seca turbo fairing, headlight cover, YICS, and a fuel additive....does it all add up to 58 miles per gallon on the Seca 900?  My tests say yes.

Yamaha XJ750D Seca

Part of my inspiration for building the XJ900 Seca-SST was this photo. Pictured here is a 1983 Yamaha XJ750D. This bike was not imported into the USA. The following information was located on the web from a gentlemen trying to sell his bike in New Zealand.  The ad read - "An excellent Touring bike, so comfortable to ride.

The XJ750D was the first model in Japan equipped with a full faring incorporating aerodynamic design. At the same time it featured advanced Yamaha electronic technologies such as the YFIS (Yamaha Fuel Injection System) and the "Yamaha Cycle Communication System," which provided a man-machine interface to give the rider information concerning the condition of the machine



It boasts a fully digital dash board with a ten function on-board fuel economy computer that includes a clock, up-count trip meter, set-able down-count trip meter, fuel remaining in tank (liters), fuel economy (as you ride, updated every 30 seconds) range on remaining fuel, time spent on trip, average speed, fuel consumption, and average economy.



There is also a seven function monitor that activates a large warning light on the dash and displays an LCD icon to warn if the side stand is down or brake, oil, battery or fuel levels are low. It also warns of lamp failure in the head or tail lights and provides a fuel gauge.



A great example in true original condition. Just a few scuff marks and a small plastic weld repair on the fairing.



Complete with a radio, tape deck and all the hard luggage you need for the "Great Touring Adventure".



4 cylinder, fuel injected, shaft drive. Starts first time and runs like a dream."

WOW! Fuel injection in 1983?!  Would love to see one of these bikes up close....just for the digital information on the instruments.  So, if you own one, drop us an email, send pics, and happy riding.  JF
secaman@gmail.com

How to improve motorcycle MPG

We want to thank all those who read, post, and comment on our Facebook, Twitter, and Blog. As we build the Retro Motorcycle Blog community, your insights, and input is valuable to us. This video is in response to a question asked by one of our readers...."how did you get the Prototype 900 Seca-SST to improve its fuel economy from 52 MPG to 58 MPG?"  This video was created to respond to that question.  If you wonder over to Aptera's website you'll read how important aerodynamics and weight are to improving MPG. We believe by applying three aerodynamic fixtures to the Yamaha 900 we achieved the 6 MPG increase. They are:  1. fitting the 1982/83 Yamaha XJ650 Turbo Seca fairing to the 1983 Yamaha XJ900 Seca.  2. MRA flip screen.   3. Plexiglas shield to headlight recess area.

Also, for another post, is the system Yamaha engineered for this era of bike.....YCIS.  Few remember that in the late 1970s and early 80s we had the second fuel crisis and fuel economy was on every bodies mind.  Yamaha had a clever solution....stay tuned.

One of the all time wonder lusts of my motorcycle years is the 1989 to 1992 Ducati Paso 906. However my passions were tempered by the early models problems with carburettors.  The following is from Wikipedia.  "In 1989 the Paso 906 was introduced to replace the 750 (the 750 Paso was the first of this body style brought into the USA), with a six-speed gearbox, a 904cc engine which provided 88hp and a 220km/h top speed. the bike still had the same automotive carburettor and unreliable electrical system, but its greatest development was the incorporation of liquid cooling. 1,802 Paso 906's were built between 1988 and 1989.
After further development, the final version of the design came in 1990 with the 907IE(Iniezione Elettronica): now without the name "Paso".  the engine remained liquid-cooled and the carburetor was replaced by the most modern Weber-Marelli IAW 043 system that integrated ignition and electronic fuel injection, which transformed the ride ability of the bike.  Power increased to 90HP and top speed to 230km/h. The wheels were changed to 17 inches, giving the bike more stability.
Despite these advances sales of this model remained sluggish, and when production ceased in 1992 only 2303 907IE's had been built".

Trying to find a 907IE may be a difficult search, however the numbers of bikes coming into the US is about double the number of 1983 Yamaha XJ900 Seca's.  Ebay, Craigslist, or perhaps even at Retro Motorcycle Blog, may be your best source.  I am suprised at the number of requests we get from active readers of our blog, and Facebook, for parts.  Let's build the Retro community together.  JF