In the early '60s we used to go down to the Honda shop and lust after the strange new Hondas with their squarish cylinders, there was all the smaller 50/150cc stuff and then there was the big stuff, the 250s and 305s, of course the 305 Scrambler and Superhawk was where all the attention was focused. Back then a big bike was a 650 (not counting Harleys) with a rare Norton or Royal Enfield thrown in. That little Superhawk was really impressive with the baffles removed, creating a noise never before heard on public streets and hitting rpm before reserved for exotic race engines. I slept in a screened in back porch and loved hearing that unmistakable sound late at night as someone was winding it out across town. Although given rides, I never owned one as my funds went to car ownership (the days when most HS kids had some sort of '50s car). When I got out of the navy in '69, I promptly bought a red '69 450 Honda scrambler which at the time I thought was about the coolest bike in the world, six months later I rode a Norton Commando, bought one, and never looked back. What a fantastic time to be young and in love with motorcycles, those visits to the Honda shop in the early '60s are Precious Memories... I consider this engine as the 'prototype' of the modern motorcycle era of which the CB750 was the actual start of... best wishes on your restoration.
Again, thought mine was bad. I thought water ingress as you can see brown liquid sneaking out during disassembly. I don't do my own engines, I have a very talented friend. I do stuff for him, paint, polishing, refurbing sub assemblies etc and he does my engines. Honda trained dealer and mechanic, sweet! My engine gave up because someone cleaned the centrifugal oil filter and didn't re-engage the chain drive successfully so it wasn't doing it's job, so, along with probable blocked oil line, breach of head gasket between cylinders and failure of one cylinder occurred. Bores OK, new piston etc on one side, other going to be ok we think (he thinks! 😂) I hope he's right because I intend to use this quite a bit. Looking forward to next part. Btw, I'm using your videos to check where things go as he took mine apart in my absence! (Cycle parts, not engine, of course).
Let met tell you how to fix that mess.I have the same problems.after you cleaned most of both cylinders i heat up both cylinders with a torch being care ful not damage anything,then ilet cool drop liquid wrench several hours then take my 2 inch of solid aluminum round block i take the top of the piston head and strik it with my 2 lb hammer doing both sides after 30 mins you will notice pistons will start to move back and force its not easy but i did it and soon be doing it soone@@ProjectDumpsterFire-tm3jt
If it were me I'd dry out the cylinders and pour some brake fluid in there and leave it for a few days. Then take a box end wrench to the flywheel and work it forwards and backwards until things start to move. Heating the cylinder with a torch might help too.
You were lucky! I had to cut mine off as the master wasn't accessible (even tried the trick of taking off the oil pump to see if I could get to it). My pistons were frozen in the cylinders, too. Quite a lot of solvents and patience to get them unstuck. Good luck!@@ProjectDumpsterFire-tm3jt
