1973 Honda CB

CB750-2230704

Clear

Up for auction is a fresh complete nut and bolt restoration of a CB750K3 in Flake Sunrise Orange with 3479 original miles, started and runs just fine. This was offered previously as un-started and did not quite get to the reserve with 35 bids so I've got it running and am re-listing. Meticulously restored to as-built in 1973 with absolutely no changes from the stock configuration/specification - the pictures tell the story. Has initial Castrol 10W-40 for oil with zinc supplement and was started with the correct non-ethanol fuel. Has an OEM NOS set of model 341 pipes (bought in 2004) with only the startup run time. Detected a typical minor leak around one of the exhaust ports when initially started which was easily corrected (shows in he initial startup video in the link below). Have completely drained the carbs and re-mounted the tins (was run off a bottle so the tank and petcock, while hooked up, are pristine and have not had any fuel). The bike should have a fine timing adjustment and final carb synch if its going to be ridden. The only remaining work is to acid charge the NOS battery and/or add the safety sticker (in-hand) for the tank which can be affixed if desired. The oil gage (used for testing) in the pictures goes with the bike as well as another gallery plug that can be easily affixed as desired. This is a barn find bike purchased in December 2004 and finally finished when it got to the front of the line. March 1973 production - Frame CB750-2230704 and engine CB750E-2243052. The restoration work was performed from October 2015 to May 2018 so not hurried in the slightest. The goal for this one was new as produced at the factory with minimal use of aftermarket bits to get it there. Trying this as a survivor project just wouldn't have worked - too much degradation from sitting semi-exposed for (from the look of it) decades. Almost 1200 parts, the vast majority CB750K3-specific hardware, NOS bolts, nuts, and washers, rubber isolators, cables, gaskets, and seals were needed to bring this back to as-built. There's a large PDF document with excruciating detail about what was done available for review as well as a video of the initial start-up, running it through the gears to verify transmission operation, and the basic electrical functions. The PDF file has full res imagery throughout with a few hundred pictures showing some of the work. Links for these are: 1. Build Notes PDF File 2. Initial Startup Video (.MOV) 3. Transmission Test Video (.MOV) 4. Electrical Functions Video (.MOV) There are also over a thousand images taken all along as well as a large Excel spreadsheet, based on the Honda parts list, that shows what parts were bought, re-used, etc. that will go with the bike. Also comes with a few spares, various parts lists, a (repro) shop manual , dealer microfiche, and a large box of some of the original parts that were replaced to illustrate the original condition and low miles as well as the original tank, rims, and tires which can go with the bike if desired. Also have the exhaust pipe boxes and packing if desired. The carbs were completely re-done by a Honda specialist to factory specs and there were no problems on startup. The bike is in Chantilly, VA in the DC suburbs - set for Local Pickup Only. It is available for inspection by appointment. The bike is also for sale locally so the auction may end at any time. There are all kinds of options for shipping and I will facilitate as possible but have no trailer capability to transport it myself - I can help load but that's it. Please contact me through the eBay system with any questions or arrangement to inspect and I'll respond as needed. Can also do a virtual look-see with FaceTime or some such as desired but has had the carbs drained out so cant easily run it in real time - that's what the videos are for. --- Read On If You Want A Little More Detail --- On inspection in 2004 the 3479 miles looked correct with the tire date codes well before the indicated production month and year. Both front and rear tire treads were entirely consistent with 3400+ miles and the rims, while fatally corroded, had no common scoring indicating any tire changes. OEM brake pad wear was minimal with pad thicknesses close to new. Motor was free in rotation with simple borescope to cylinders, oil pan, and oil tank showing minimal wear. Both speedo and tach were still sealed in their original enclosures although faded/corroded externally. Air horns still pliable in the airbox with minimal distortion and hardening indicating minimal thermal cycling – had the original air cleaner element in pristine condition. Had an OEM oil filter in place on motor disassembly. Looked like it had been sitting for most or more likely all of its previous life having been partially covered on the rear. Looks to have been parked on the side stand the whole time and just left with no preparation. The fuel system was goo and varnish, the original tank a complete loss from extensive corrosion but with zero impact or tip-over damage. Had the undamaged side covers and original exhaust system - unfortunately completely shot with more rust than good metal. Based on all of the above I purchased it, brought it back to Virginia, and stored it inside and covered. To correctly re-paint the engine cases they had to be split so they were completely disassembled the motor to make sure it hadn't been parked and left because of a blown engine. On teardown all the rubber bits were like new – primary chain stretch was at the bottom of the range with very minor oil residues in the nooks and crannies of the bottom case. All internal wear measurements for cylinder bore, valve train, and so on were minimal - piston ring gaps measured in their matching cylinders were all at minimums indicating low wear and usage. Model 341 OEM pipes and a seat were procured in late 2004 and stored inside in a conditioned space. Given the bike’s degraded condition virtually every external nut and bolt was replaced as well as all the gaskets and seals - the frame and center stand were fine with only surface rust. In all just under 1,200 individual parts were purchased - the vast majority CB750K3-specific hardware, NOS bolts, nuts, and washers, rubber isolators, cables, gaskets, and seals. The bulk of the Honda NOS parts were bought in the fall of 2014, mostly from Partzilla with the other more hard to find bits from David Silver in the UK, Yamiya in Japan, and a few vendors in Germany and Canada. A few used OEM to replace assemblies that were past it (front caliper, taillight, and grab bar/rear signals) as well as the usual consumables (plugs, chain, brake shoes, and period tires). The side stand which was straight but had heavily corroded on the bottom from contact with the ground for so long was also replaced. Aftermarket was a few long fasteners, tins/fork ears set from Yamiya, both sprockets, an excellent reproduction owners manual, decals, idiot light holder plate, rubber vibration pads, and handlebar. Only four things were outsourced: tire mounting (I did the lacing and trueing via stand and dial gauges), complete carb set restoration (Mike Nixon in CA), frame and associated bits for powder-coating, and finally the soda blasting of the engine cases, oil filter cover, and timing chain adjuster cover that were re-painted. The engine re-paint was accomplished with a temporary enclosure when the temperature and humidity was just right, using a dedicated 27" double oven for initial and then cycling cures to simulate engine operation to get ahead of the finish durability.