Topic: 1980650c carbs

[lustmaster]

any help would be great,,

1980 CB650C

1st bike wont run right with out full choke, i pulled the air box and am running four pod filters, (i pulled the carbs apart and cleaned every last part i could find) still runs rough. looking to find decent carb gaskets and new jets any ideas?

2nd looking to find a source for a rigid frame i have found a few but are for the 750's is there any difference in the frames or will it work?

3rd on the center valve cover there is a vent built in i assume it is a crankcase vent as i have no airbox can i just stick a small filter over the opening or seal it off totally?

[onepieceatatime]

any help would be great,,

1980 CB650C

1st bike wont run right with out full choke, i pulled the air box and am running four pod filters, (i pulled the carbs apart and cleaned every last part i could find) still runs rough. looking to find decent carb gaskets and new jets any ideas?

2nd looking to find a source for a rigid frame i have found a few but are for the 750's is there any difference in the frames or will it work?

3rd on the center valve cover there is a vent built in i assume it is a crankcase vent as i have no airbox can i just stick a small filter over the opening or seal it off totally?

Welcome
Pods cause a lot of problems with the way these bikes run. '79 CB650 carbs are the same bodies, I think the jets are different. I have seen rebuild kits listed for '79 but not '80 on some sites, but can't remember where right now.
No idea if a 750 frame will work or not, but I would guess not. The 650 engine is more like the 550 engine.
It is a crankcase breather vent, I would go with a filter instead of trying to seal it.

I like the paint color.

[cb650]

Yes some sites list the 80 in with the 81/82 carbs.  Can only think its cause of the style change.  But your carbs are the same as 79.
I like the color too.

[lustmaster]

are there any other options for carbs,, from different years or even a different bike all together. I hate to sound like a newb lol but what are the differences in the cb650c and just the cb650.

thanks my 5 yr old daughter and I worked on the tank as we watched Dora she just sanded away happy as she can be happy daddy out with my bike.

[cb650]

As far as 650 carbs any 79 or 80 will interchange.  750 carbs will fit but then you need to play with jetting. Sounds like you will be anyway. 
The C is the custom. But then not always.  Custom and standard had a few diffs wheels and exhaust mostly.  several other small things too.  Engines are the same though.

[trueblue]

http://forums.sohc4.net/index.php?topic=40287.0

The carbs from a Suzuki GS650E will swap onto a '79-'80 650, you use the boots from an '81-'82 650 either side of the carbs, the choke cable swaps straight on, remove the pull cable,  swap the push cable into the pull cable spot.  Make an adapter from a 5mm fuel line to an 8mm line.  You need to separate the carbs and modify the engine side a little.  Shorten it a little and move the groove for the boot to slip into a little closer to the engine.  I haven't gotten to the stage of playing with the jetting as yet.

[bollingball]

3rd on the center valve cover there is a vent built in i assume it is a crankcase vent as i have no airbox can i just stick a small filter over the opening or seal it off totally?
 Seal it off to go with the pods. jk Good luck
Ken

[lustmaster]

lol if I knew that no airbox would have been a big deal i would have fixed the old one and kept it, when I got the bike it was cracked up badly and missing the filter and cover.

I have been thinking of swapping in a springer front end to go along with the rigid tail, any info on that would be great, measurments and such, my bike is sitting in a storage shed buried in snow so its hard to get in and see for my self,

[kslrr]

Here is what I did on my '81 Custom with the '79 engine with EMGO pods and stock pipes:

Carb body PD50B
Slide          56B
Needle       35B
Idle jet       47
Main jet      110
Pilot screw  1 turn

The slide was part of the original 50B carbs, the needle came from a set of 50A carbs.  It is still slow to warm up, but once it is it seems to run well.

Don't seal the top vent.  Put a small filter on it, or run a tube down the back.

[Tugboat]

1980/81 CB650s have the slow jets that are pressed inside tubes, and are therefore not removable without considerable effort. They changed them in 1982 so that you could easily remove the slow jets. You say you cleaned the carbs really well - I don't doubt you, but my bet is on those slow jets not being totally clean.

[cb650]

No the 80 is the same as 79.  Can be removed with care.  81 is totaly diff and "non removable".

[grasscutter]

No the 80 is the same as 79.  Can be removed with care.  81 is totaly diff and "non removable".

Yes.

And agree that the carb are not clean.  Buy a gallon of carb dip and let them sit overnight.  Carb spray, and then blow with compressed air.
Might have to soak them more than once. 

Pod filters seem to affect running performance @ higher rpms (and not in a good way).  With pods, @ idle, you should still be able to get it to start smoothly and idle correctly, if carbs are clean and in sync.