1160cc RC Engineering 1978 CB750F3 Super Sport motor for sale with-w/o chassis

Engine for sale at $5k or whole bike for $6500. I bought this bike w/o full knowledge of what had been done and what it needed. Engine build was done with many RC Engineering parts. but apparently even Russ Collins did not recommend the stroker motor for the street. With 210psi compression and 1160cc displacement. the electric starter will barely turn it over. The bike didn't even have an electric starter when built. which I added afterwards. I adapted a starter clutch to the RC Engineering lightweight rotor and installed a used electric starter motor and drive gears. It did start up a few times with a fresh battery and I was able to drive it a few miles. Once the motor heated up. the starter system wasn't able to turn it over again. but the motor ran great. shifted well and was very tractable. I didn't check the charging system output. Probably the only way to use this motor on the street is to remove the stroker crankshaft and rod kit. A stock cam might make it easier to start. as well. It may be possible to put a smaller top end on the stroker bottom end. but the liners would have to be notched to clear the wide RC Golden Rodsand the top rod end eyes are too wide for OEM pistons. I am not a seasoned CB750 engine builder. so these suggestions are just good guesses or some ideas from CB750 engine builders who have come forward with information on these engine builds. As you see. the top end was disassembled and the engine mods verified just the way they were described when I bought the bike a few months ago. Obviously the only way to know what was inside was to tear it apart. All internals are in fine condition and ready for reassembly in some form. but rebuilding it. the way it is. will not make a good street bike due to hard starting issues. These are premium NLA engine parts that are rare finds now that Russ Collins has passed away.  I am open to partial trades for collectible 1960s Honda motorcycles or even a Toyota Tacoma X-Cab truck swap. If the motor doesn't sell as a unit. then I will tear it down after I have found a stock replacement for the chassis. I will be removing the rear swing arm setup and replacing with OEM parts. as well. unless someone buys the whole package. I have installed a stock centers stand as the one that was on it was shortened down below a level of usability. I have a stock swing arm. but am looking for hardware to complete the conversion back to OEM specs.  RECAP:

R. C. Engineering (Russ Collins) 73mm pistons/sleeves with 1/4" stroke = 1160cc (approx) Pistons are approx 73mm with aluminum wrist pin buttons.

Bored K1-K7 series carbs with NOS intake manifolds

Heavy Duty RC Engineering Golden Rods

Headwork by RC Engineering  with Stainless Steel Valves & Big Cam/valve spring kit (RC cam number 327) . 368" lift. 325 degree duration. according to timing tag paperwork.  

Head stamped "RC Engineering" and a serial number.

Lightened Alternator & Modified Clutch

Kicker Shaft Modified (can be changed without pulling engine)

Trans. Gears back cut. to prevent disengagement

Heavy Duty Cylinder Stud reinforcement package. Modified top cover for strength.

Included is an RC Engineering timing wheel. spacer for the lightweight rotor. if you remove the starter clutch.  

New Dyna Electric Ignition

Chassis info:

Stock Frame with two frame tubes removed for in-frame engine service.  

Modified. extended 3-position swing-arm (three axle positions and shock mounts)

Double Row Drive Chain and Sprockets

Drilled Double Disc Front and single Disc rear Brake Rotors

RC Performance 4:1 exhaust system

Second petcock added to the bottom of the stock fuel tank

Bike has very low miles since entirely re-vamped - New rings approx. 50 miles back

Bike was built with no electric starter. back in the 1980s.  I have added the stock electric starter system back on the engine and modified the lightweight RC rotor to accept a starter clutch.  

Both master cylinders and all three calipers were rebuilt. New K&N pod air filters added. New Dyna Ignition system installed. Stored since 1996. Unsigned/undated CA pink slip available. but bike should be out of DMV system. Flat drag bars installed. tight fit but it all works. There is a headlight bypass switch mounted on the left handlebar bracket.

Compression is 210 PSI cranking. Carbs cleaned out (main jets. jet holders. idle jets and float valves). Current main jets are #130.  Russ Collins referred to these motors as "Cobra" engines for the maximum amount of bite they could inflict on the rear tire. I think. The scorched rear tire tread bears testament to the bike's power potential.  The bike is running and driveable. but needs a bit more work on the electric starter system to bring out its best qualities. About $500 was just spent on starter parts. brake repair parts. a new Dyna ignition and a full set of OEM Honda intake manifolds. $6500+ invested to date. This is a very rare one-of-a-kind machine that would cost about $5k+ just to replicate the motor according to vintage CB750 Experts. Buy the motor or the complete bike package. If no sale. the auction will not be relisted until sometime in January after I recover from knee surgery.  

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