This 1974 CB750K was found in Montrose, Colorado. It belonged to a guy who rode it from San Diego, California in the late 90's to Montrose. Registration slips found in the original Owner's Manual indicated the bike may have started life in Maryland near Annapolis.
When we found it, the bike had been parked for 8-9 years on its kick stand, however, the engine did turn over with the kick starter. The front caliper was locked on the disc and you could not rotate the front wheel. We were able to loosen the caliper and roll the bike into a pick up bed and take it to Grand Junction; that was in late October 2013.
After doing some clean up work, we were able to start the engine a few months later. Then we pulled the carbs and had them ultrasonically cleaned and went about rebuilding the carbs. In addition we purchased a new master cylinder and brake pads and restored the front brakes. We continued to clean up the bike, licensed it and put it on the road in July, 2014. We put around 60 miles on it and determined that it was a worthy candidate for a restoration and started taking it apart in November 2014.
As you can imagine the ride was pretty sloppy and there were lots of electrical issues. We discovered during the work that this bike is an early 1974 model with an engine similar to the 1973 CB750 bikes.
All in all here are the major things we did to the bike:
Removed the engine from the frame and did a top end. We replaced the rings, had the valves ground and honed the cylinder head; including all new gaskets, O rings and oil strainer.
Rebuilt carbs, and installed new OEM (from YAMIYA) engine and air box rubber connectors
Polished all the aluminum engine parts
Painted the engine
Re-chromed the rims, fenders, handlebars, tail light, and other small parts
Replaced front and rear wheel bearings
Replaced old spokes in front and rear wheels with new stainless steel spokes
Put on new tires
Sandblasted the frame
Powder coated the frame, swing arm and other frame parts
New master cylinder and front brake pads
Replaced rear brake shoes
Rebuilt the swing arm with new bronze bushings
Installed All Balls steering head bearings
Rebuilt the front forks with new progressive springs
Installed Hagon Shocks – $$$ love 'em!
Installed new handlebar controls – right and left
Installed a new wiring harness; upgraded to electronic winker
Installed new Oregon Motorcycle Parts, rectifier and voltage regulator
Installed all new OEM cables (throttle (2), clutch, speedo, and tach) from YAMIYA
Installed Hondaman's Transistorized ignition and blade fuse box
Installed new MAC 4 into 2 exhaust
Modified the headlight mounts and front turn signals; did away with the gators
Repainted the tank and aftermarket side covers custom candy orange
Recovered the seat
On June 4, I rode the bike to the 8th annual Palisade Vintage Motorcycle Show in Palisade, Colorado. The bike won the People's Choice Award and 3rd Place in the Asian class. This was quite rewarding; but the real reward came from seeing a number of new friends that we have met during this build. In addition the support I got from the SOHC Forum and in particular Mark Paris was great. It is nice to bring back an old piece of vintage motorcycling. Our next project will be to cafe a 1970 CB750; provided we can save the engine.
