Mikuni BSW30SS Carb Info

[fenderfreek]

Dredging this back up for some more info here...

Does anyone know if there are any particularities to cleaning these? I've done everything else to my ride but clean the carbs, but I've been a bit leery of doing so since there's really no guides to speak of on cleaning and tuning these.

I got a o-ring set for CV carbs, and hopefully the rings in there can be used with these goofy Mikuni's. I'll try to take photos when I do break them down and do a little writeup like the wonderful tutorial on "normal" carbs.

 

[Calvin Blackmore]

Dredging this back up for some more info here...

Does anyone know if there are any particularities to cleaning these? I've done everything else to my ride but clean the carbs, but I've been a bit leery of doing so since there's really no guides to speak of on cleaning and tuning these.

I got a o-ring set for CV carbs, and hopefully the rings in there can be used with these goofy Mikuni's. I'll try to take photos when I do break them down and do a little writeup like the wonderful tutorial on "normal" carbs.

These carbs are not goofy they are siamesed to save space to allow for design flexibility.

Bah some folks still arent over square headlights in spite of the advent of composite designs.

KZ 1300 had sianmesed carbs as well.

no different to clean than any other carb in fact a wee bit easier due to half the number of floats and float valves.....

while yah gots em off change the intake o rings

 

[fenderfreek]

I did change the intake o-rings, but hadn't gotten around to deep cleaning the carbs themselves.

I guess "goofy" probably wasn't what I was really going for, but they are comparatively "odd" so I wanted to make sure there wasn't anything I'm missing here. They're definitely not covered as much as all the other BS carbs. I did notice that the caps on the mix screws are gone, so someone's tweaked them along the way.

My problem is that it won't start without the choke wide open, though warming it up on partial choke for a minute or two lets it run without any problem. I've done the coil mod and inspected, adjusted, and/or replaced the plugs, valves, intake o-rings, airbox, and boots, so the only thing left to tinker with is the carbs themselves.

My gut tells me the mix screws just need tweaking, but since I don't know anything about the service habits of the PO, I'm just gonna break em down and dip everything to be sure.

I've treated everything as if the PO hadn't done any service at all, and so far my assumption has been proving to be very prudent. The valves were way too tight and the intake rings were hard as a rock and flat as a pancake. It's doing much better, but there's still work to do before it runs the way I want it to.

 

[Matchless]

Go to BassCliff's website and download the workshop manual for the 1983 GS550 ES (the TSCC) model 16 valves.
Hope this helps.

Link: GS550E/ES/L Servivce Manual '83 (149MB)

 

[Kudagra]

Just for reference I drilled the plugs out on a spare set of carbs I have and they were set at 2.25 turns from the factory.