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Newbie w/ a 1980 CB750 Super Sport - tips on parts sourcing and waking her up?

tdskip

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First of all, good morning and happy Friday.

I was looking at SOHC CB750s (with excellent support from the SOHC guys here) but nothing came together when I came across a well cared for 1980 CB750 Super Sport locally. It has been stored (inside) since 2007 so it is going to need some recommissioning after sitting. It was adult owned and ridden and was in good running condition with parted due to health (prior owner was 70 when he last road it). I am super excited to get her back on the road but was hoping for some coaching on doing this right.

Parts sourcing - is there a go to that you would recommend for service items such as brake and clutch lines etc?

Serving prior to riding - obviously I need to change her fluids and I am assuming brake lines and tires? The electrical system came up with a fresh battery but I didn't try to turn it over. The shocks feel OK and the seals aren't leaking. Brakes appear to work. Fuel tank is dry and rust free. I am assuming the carbs need to come off and any old fuel / gunk taken care of. Any do/don't I should be thinking about here?

Thanks in advance for the help.


1980 CB750 Super Sport.jpg
 

amc49

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Adjust the valves, most never do it and why so many of them will not run right and then burn valves too. Use .005" as your go-to clearance number if you want it to live. The valves burn set at .002" even though the service manual says that is within spec. Don't you believe it.

Don't dump the OEM airbox either, many do to go to pods and then the misery sets in, these do not like pods AT ALL.

If gummed up expect to have to clean the carbs more than once, most do, the carbs are VERY particular about being 100% clean, 98% won't cut it there. '80 model is more problematic since the pilot jets (under the rubber plugs) are not screw-in, they are pressed in and you cannot yank them to check the top of them for clogging at emulsion holes. The aircuts on left side of each carb can make issue too.
 

tdskip

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Thanks @amc49, appreciate the response and tips. Will make sure to keep the OEM airbox.

On the carbs pull them and do a full service including soaking them in a solution and then blow compressed air through them?

Is there a go-to parts supplier for this bike you'd recommend?

Thanks!
 

amc49

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Yes, provided they have worked out the kinks of international parts ordering.

You absolutely cannot soak the carbs without breaking the rack apart, it will ruin all rubber parts and there are a lot of them. Aircut diaphragms are the worst. You need to match all parts to where they go and most especially the slides to the top carb caps they go with.
 

tdskip

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Thank you for the tip, sounds like I need to just bite the bullet and fleetly disassemble the carbs otherwise I might be causing more problems than I’m solving.

Sidenote – some of the old British cars I’m familiar with use a rubber diaphragm system and it’s very common that new owners spray carb cleaner in it which disintegrates the rubber die friends and their problem goes from bad to worse.
 
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