Carb Rebuild? or ?

Chrisraven

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I just got a 1980 750 Custom. A good barn find actually; if has been sitting for the better part of 32 years. This was a really "pig in a poke" gamble for me. When I looked at it, all the parts were still on the bike but no battery or kickstarter to see if the engine was seized. I paid $900 Canadian for the bike delivered to my place. Upon inspection I found the exhaust was pristine, no rust no dents nothing. Did a compression test and got 145 to 175 across the cylinders, took off the seat and everything was still tied down with Honda straps straight from the factory. Had the original battery in it, which was surprising.
Checked the oil and it was like brand new never used.
This has lead me to believe that the original owner "winterized" the bike and then never rode it again. I did put lube in the cylinders and left it there for a couple of hours, then put back the spark plugs, jumped a new battery onto it, used a remote container of gas and gave the starter button a push. Turned over great and fired up almost right away.
First run was for a couple of minutes, seemed to run rough and did not want to idle, (asking a lot, I know...lol) Left it for a couple hours and went to start it again, this time it started right up with no choke pulled on. Still would not idle below about 1500 but ran a lot steadier at 2K and above.

Question: What is the forums opinion on rebuilding the carbs? Or just do a good clean and replace the gaskets?
It has the original points system on the bike, would it be worthwhile to change those over to a solid state ignition system? Apparently I am allowed to do that and still maintain collector plate status from ICBC.

I also have to unstick the from rotor piston, seems to be seized onto the caliper. Is it worth redoing that one or is it better to replace the piston and gasket?
 

amc49

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There are no points in it. I have never seen one ever that would start cold with choke dead off showing likely running rich and what the clogged carbs usually do.
 

Chrisraven

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I just made the assumption that the 750 had points in it, I had in 1976 a 76 750 Four. Nothing in the 750 line since. Have had a few Goldwings and the only one I had to work on was a 1977 GL1000 and it had points. How is the timing adjusted?

What are your thoughts for repairing the front rotor?

Thanks
 

amc49

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You generally never need to mess with timing on one. It does have a plate that can be moved to do it.

Caliper is likely corrosion sticking outboard of piston like most of them do. Caliper comes apart to clean up outward piston OD and new seals going back in. No need to change piston unless it has pitting over the working distance.

http://www.cb750c.com/publicdocs/SeanG/Honda_Carb_Manual_revG.pdf

The carbs often need more than one time going into...............be warned.
 
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