CB750F1 Project

[martin_uk]

Bought bike from friend who told me the engine was seized from standing and probably needed a light hone and rings!

2014_0425cb750B40028 by nitram2010, on Flickr

I think it has an early Honda worm drive
 

2014_0425cb750B40025 by nitram2010, on Flickr

[martin_uk]

Head was badly corroded

2014_0425cb750B40023 by nitram2010, on Flickr

2014_0427cb750B40009 by nitram2010, on Flickr

[preyno2]

Goodness me!

Where's it been standing, in the garden pond?

[Trigger]

The last picture looks like someone is using the wrong tool to clean it up.

[preyno2]

I don't know whether it's badly corroded or part of the piston ring has been bouncing about in the chamber

[martin_uk]

The last picture looks like someone is using the wrong tool to clean it up.

Just a rotary wire brush, the metal had corroded so badly .

[Trigger]

Can be repaired but, the cost would be sky high. It would need everything.

[martin_uk]

Plus the right front engine mount is broken 

2014_0502cb750B40094 by nitram2010, on Flickr

[Trigger]

You have a very nice mate that sold you that.

[martin_uk]

Pistons took some shifting!

2014_0426cb750B40008 by nitram2010, on Flickr

Diesel soaking

2014_0426cb750B40001 by nitram2010, on Flickr

2014_0426cb750B40010 by nitram2010, on Flickr

[martin_uk]

You  can see the engine looked quite corroded

2014_0417cb750B40017 by nitram2010, on Flickr

[matthewmosse]

I had a cb550 head that had similar dammage. In my case a previous owner had broken all the top rings, several of which had smashed out of the top of the pistonand scratched and dented the head up something chronic. They had obviously been in there, removed most of the debris, sealed up again re using old gaskets and leaving bits of broken ring in the sump and blue gaskett goo behind as a calling card. I bought thd bike taxed and tested, rode it a bit and found it was ok to ride but if stalled when hot it wouldn't restart until cold. It also leaked oil, but it wax also cheap. I only found the dammage when deciding the oil leak should really be fixed. I bunged on a decent set of barrels and pistons from a scrap engine, and re used the well scarred head. It ran for years like that, never down on power or hard to start after replacing the wrecked pistons. It eventually dropped a valve, many years later. Still have the remains somewhere.

[UK Pete]

Blooming heck fella that engine is a very bad starting point,
pete

[cb ghia]

2014_0425cb750B40025 by nitram2010, on Flickr

What in the hell is that thing?  Is that a worm?  You must have very different worms on your side of the pond.

[Spitfire]

Unbelievable, poor bike.