Re: 1981 CB750 Cafe Build Project

Posted by Jefe06 on Jul 01, 2012; 3:37am
URL: http://vintage-and-classic-hondas.81.s1.nabble.com/1981-CB750-Cafe-Build-Project-tp4023693p4024018.html

RR, yeah that was a thought of mine.  I probably will end up doing that since my wiring (other than at the connections) is in decent shape.

As for an update my my current project.  I manager to run a compression test on all of the cylinders.  I have kind of mixed feelings about the results, but the bike has been sitting for awhile and I think that one of the exhaust valves maybe gummed up.  On cylinders 1-3-and 4 I got about 150 psi max with throttle wide open.  The #2 cylinder gave me something like 90 psi.  I ddin't check it by putting some oil in the cylinder and rechecking the compression, but I do think that the exhaust valve may be leaking.  Ijust have to get the bike running and put it through its paces before knowing if any malfucntions is from just sitting or actual damage.

I pulled the carburators off and they are pretty well gummed up not to mention the No.1 cylinder is missing the float bowl and floats, among other things.  I have a set of carb rebuild kits and with the help of this forum and the FSM I will be getting them back to where they need to be.  

I got the engine to fire and run for a feww seconds today with some starting fluid.  It really sounded good, but I wont be able to tell definiativly until i get everything running fine.  I connected the bike to a car battery today and it turned over fine and fired.  I'm just not sure if the starter will have enough power to turn the engine if I use a new bike battery.  Any help with getting the starter more juice would be greatly appreciated.

It also looks like I have a leak on the valve cover just above the the No.1 carb.  I will need to address this as well.  How do you guys feel about liquid gasket?

Homework for the next week or so will be to get the carbs in operating condition and get a float and float bowl.