CB1000C Cafe Racer "Rat Bones" Project

My project  goal is to create an inexpensive, reliable and good-looking cafe racer style motorcycle. The first cafe racers were British. Given that the old British bikes are anything but cheap and not all that reliable (according to some), that put British iron out of the running.  The venerable Honda SOHC CB750's have become a popular choice for cafe racers, but the supply of these bikes is running low, and low supply plus high demand equals too much cost.  So, I began my search for a suitable Japanese motorcycle that would fill the bill -- DOHC Hondas are still plentiful and can be had for very little money, so I set out to find one.

I ran across a CB1000C for sale for $850.  The bike looked complete and after a test ride, I decided to buy it for my project "Guinea Pig."  It was certainly ugly enough, in my opinion, for sacrificing to the Cafe Racer gods.

Well, I soon found out that the CB1000C was a one-year production model and has a small, but devoted cult-like following.  I had a momentary pang of guilt when I realized that people were spending their cash and time trying to keep these beasts in stock condition and restoring the CB1000C to it's early 80's, ahem, glory.  I quickly got over my guilt when I realized I could sell off stock parts to help hold the cost down on my project - the stock seat, grab rail and shocks where first to go on the auction block, along with the stock turn signals.

So, follow along in my photo gallery as I attempt to transform the CB1000C from a disco king to a rockers ride....

NOVEMBER UPDATE

I've made a lot of progess - check out the photo gallery to see the changes from the stocker to now.

I've finished the cafe seat, replaced the stock turn signals with smaller aftermarket signals, installed a "4 into 1" exhaust, blacked out the top triple tree, headlight bucket and gauge buckets. I chopped the front fender and blacked it out too.  The rear fender is now gone and I added an LED tail light plus a sport bike license bracket to clean up the rear.

I installed "euro bar" handlebars - while these are not the usual Clubman style normally found on cafe racers, the euro bars improve the look and feel of the bike.  I'll add Clubman's later in the project.  I've also replaced the air shocks with standard exposed spring rear shocks.  I replaced and/or rebuilt hardware that looked worn or corroded.  I replaced the ignition switch too.

My engine started smoking.  The number 1 cylinder decided to eat a valve - I started down the "rebuild the head" path, but I worried about the condition of the bottom end.  Fortunately, I located a CB1000C engine through the forums for less than I'd spend on rebuilding the engine.  Best of all, the engine only has17K miles on it and the tear down revealed no problems.  This is a good deal, considering the engine in the bike has 78K miles on it!

I'm now at the painting phase - paint will really change the look of the bike.  The drab battleship gray will be replaced with black.

Stay tuned for more changes!

"Rat Bones"

LATE NOVEMBER UPDATE

The black paint is now finished.  I went with a plain gloss black to keep the cost down (no graphics - keep it cheap).  The side covers and tank are done and look good.  The lower mounting points for the stock side covers have a tendency to crack at the stress points, so the weak points have been "welded" and smoothed.  Also, the side covers are known to fly off while riding down the road, so I've replaced the rubber mounting grommets to tighten up the fit.  I'm working on adding a positive (bolt) type mounting system to really secure the side covers (they look too good to lose on the road).

RB

DECEMBER 2008 UPDATE

Things have slowed down thanks to the holidays.  I've picked up a new clutch perch and associated parts as I intend to powder coat the controls black for looks and durability.  I installed new bearings and seals on my CB700SC front wheel and I'll install it as the next modification.  I also have ordered the Clubman handlebars. I had a freebee coupon from JC Whitney. I figured I'd get the bars and try them out (how could I pass up a free set??) - so stay tuned as the new front wheel and bars will show up in the January update along with some other changes.

RB

JANUARY 2009 UPDATE

The Rat Bones Project is still moving along slowly.  The front wheel is installed and  I'm waiting on a new rear wheel to match up tires.  I tried out the Clubman bars, but I'm not happy with the look due to how I had to angle the bars to miss the tank and account for the pull-back risers. Kevoz from the DOHC Customs forum pointed me in the direction of some bars that look like they'll work.  Speaking of the DOHC Customs forum, I've added an album to the gallery to highlight two Cafe Racer projects:  Kevoz's 1979 CB750K and Austingrackle's CB1000C project.  Kevoz is building an outstanding Cafe Racer and I'm really amped to see another CB1000C Cafe Racer project in the making.  Check out both projects in the gallery.

Cafe Racers (the riders and the style of motorcycle) had their origin in Great Britain during the late 1950's and 1960's -- Triumphs, BSAs, Nortons, and other British motorcycle marques were the basis for the cafe racer.

Per Wikipedia, the cafe racer is a motorcycle that has been modified for speed and good handling rather than comfort. The cafe racers' bodywork and control layout typically mimicked the style of contemporary Grand Prix roadracers, featuring an elongated fuel tank and small, rearward mounted, humped seat. A signature trait were low, narrow handlebars that provided more precise control at high speeds and allowed the rider to "tuck in" to lessen wind resistance. These are referred to as either "clip-ons" (two-piece bars that bolt directly to each fork tube) or "clubmans" (one piece bars that attach to the stock mounting location but drop down and forward). The ergonomics resulting from low bars and the rearward seat often required "rearsets," or rear-set footrests and foot controls, again typical of racing motorcycles of the era. Distinctive half or full race-style fairings were sometimes mounted to the forks or frame.

The bikes had a raw, utilitarian and stripped-down appearance while the engines were tuned for maximum speed. These motorcycles were lean, light and handled road surfaces well. The most defining machine of its heyday was the homemade Norton Featherbed framed and Triumph Bonneville engined machine called "The Triton". It used the most common and fastest racing engine combined with the best handling frame of its day, the Featherbed frame by Norton Motorcycles. Those with less money could opt for a "Tribsa" - the Triumph engine in a BSA frame.

Everything you wanted to know (but were afraid to ask) about the CB900C and CB1000C:

The Honda CB1000C  was a "custom"-styled standard motorcycle produced by Honda in 1983 only. The CB900C and CB1000C are derivatives of the DOHC CB750K produced at the supposed requests of the American consumer. They were equipped with a handful of features that are unique for the time. These included air assisted suspension front and rear, shaft drive from the GL1100 Goldwing of the same time period, and most notably, a dual range sub-transmission that allows the operator to "split" any of the five gears in the main transmission for a a total of ten driveline ratios.

The CB900C used an air/oil cooled DOHC 902cc engine with 4 32mm Keihin CV carburetors and electronic pointless ignition produces 84 BHP @ 8500 RPM. Front suspension relies on air pressure for preload while the rear relies more on air for the actual spring action. Three disk brakes arrest the momentum of the considerable curb weight as listed in the Honda FSM (Factory Service Manual) as 611 pounds or 277kg.

Both Rider and Cycle World reviewed the CB900C in 1980 with varying degrees of disregard and dissatisfaction. The top complaints were the lack of purity in the "custom" styling and its effect on function regarding sport or spirited riding. The soft suspension was recorded as a hindrance to cornering ability as was the highly reactive shaft-drive/sub-transmission combination and the huge mass of the machine in general. Comparisons were made to tractor trailers. The bike garnered some appreciation from Cycle World for its styling and tank design.

The genesis of the CB900C and CB1000C makes them "parts bin" bikes. Honda produced two shaft drive bikes previous to and concurrently with the CB900C/CB1000C. The GL and CX series of touring motorcycles of the time are the source of the final drive and rear suspension assemblies of the CB900C/CB1000C. The European model CB900F supplied the basic frame extended two inches for the sub-transmission, engine, and many other chassis components. Full Hondaline touring equipment (Fairing, Lower Leg Fairings, Saddlebags and Trunk were available from the Honda dealer to make the CB900C and CB1000C complete Touring Bikes.

The Sub-transmission is used as a "jack shaft". That is, in order for Honda to use the CB900F engine in conjunction with the GL swingarm and final shaft drive, power must be taken from the CB900F's left hand power take off and transferred to the GL's right hand side final drive shaft. The "Jack Shaft" was given 2 gear ranges ranges at relatively low cost. Most CB900C/CB1000C riders use the 2-Speed Transmission more like 6th gear overdrive. Leaving the bike in low range while shifting through the normal 5 gears, then shifting into high range once up to speed on highway, reducing engine rpm significantly at touring speeds.

Despite the lackluster treatment of the bike by the media some 27 years ago, the CB900C and CB1000C have gained a small cult following. This phenomenon is not due to any one particular attribute of the cycles, but rather to a culmination of appreciation for their uniqueness (10 speeds), styling, comfort, reliability, and ample power output. "It looks like a bike should look," says a member of the "CB900C CB1000C Custom Club" on Yahoo! groups (well over 2,000 members strong). The CB900C CB1000C Custom Club had been around in its current form since September 14, 2000 and existed on many other forums for several years before settling on the Yahoo! Groups forum. One of main reasons for the clubs existence is to help owners get as many of these bikes as possible back on the road.  Additionally, the DOHC Customs forum (825 members) is another popular forum for owners of the CB900C and CB1000C.