Non-runner CB 750

[wernwilk]

Hi all,

new to the forum.
Just picked up a 78 CB750, (not sure of the actual model sorry), and its a non-runner.
The history of the bike was that it turned over for the previous owner a while before catching and firing then after a run was fine...this got gradually worse for a few months until one day it gave up altogether.
He then parked it up until this day, (prob 6 months or so).

I have yet to raise a wrench in anger at it and was going to do some basic checks, i have zero experience with the CB and wondered if any of you knowledgeable fella's had some go to checks with this model.

Many thanks.

[sgtslag]

Welcome to the Forum!  Have you checked the basics:  fuel (gas making it through the carburetors, into the cylinders), air (clean, OEM type air filter passing air/pod filters), spark (fully charged battery; plugs firing, wires in good condition, etc.)?  Oil level, and quality (clean, liquid, instead of thick sludge)?  Does it turn over?

The FSM is available for download on the Home page of this site.

The actual model/version can be found on the steering stem:  there is a label, with the year, make, and model, listed on it -- turn the handlebars all the way to the side, and it will be easy to see.  Let us know more details, and we'd be happy to help.  Cheers!

[Magilla]

Fuel; does it have it?  is it getting to the carbs?  give it a shot of starting fluid.  If it starts and then stops you have a fuel problem.

Spark; does it have spark at the plugs? Pull the plugs and make sure they are clean and gapped correctly.

Points; are the set correctly?  There are free service manuals out there to explain how to set your points.

Not much more to it in order to have it run.  getting it to run well is a differnt story.  That could require a bit more work BUT this will help isolate the problem.

[Re-run]

As sarge says, get the manual here. Start with doing the full tune-up to get everything to spec. Head from there. It is always best to start with a baseline before you start monkeying around.

[wernwilk]

Cheers for the initial advice fella's.
I honestly have not been able to get into it yet as I haven't had time but will have time next week to check the basics and then crack on from there.

As soon as I get an idea of where we are I will post right back and get your opinions.

Thanks again.

Matt.

[shinyribs]

If it is going to be a while before you get to start tearing in to it,and depending on what you think might need done,now would be a good time to spray some PB Blaster,or whatever penetrating oil you use,and let it be working til you get around to it.

Good luck with your bike!