'82 GS550L Carb Swap

[Guest]

I have a '82 GS550L, with a4 into 1 pipe and Surprise..... PODS. I want to scrap the OEM CV carbs and go with Mikuni smoothbores. I know that is will be a bit spendy. Has anyone done this? Any recommendations or advice?

[schankes]

PS.... Great site and thanks so much for all the information! I find myself spending alot of time digging for knowledge and enjoying all the posts.

More about my bike. I'm converting to a cafe racer and it's a work in progress. About 75% done cosmetically and 50% mechanically. It's been slow going as I decide on what I want to do. I also have a '82 GS550L that I want to restore to stock after I finish the cafe.

[ShadowFocus603]

Do you have a specific reason to not want to use the CV carbs? Are they in poor shape or? Pods and a pipe aren't the end of the world and having CV carbs makes it much easier to jet for them since you can get a Dynojet kit and be pretty much set in a single go.

[Steve]

I want to scrap the OEM CV carbs and go with Mikuni smoothbores.

What size smoothbores and just what do you hope to gain with this swap?

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[Nessism]

Don't think there are any "smoothbores" in an applicable size for a 550. You could convert to VM carbs off an early 550, but you will have to figure out some sort of carb boot conversion.

[schankes]

Hey thanks for the fast reply. I was thinking about RS34's but I really need to take some measurements and do a bunch more research before I decide.

To be honest, after reading all the posts here and other places regarding how hard it is to make the GS550L run really well with the CV carbs and PODS without the airbox, I'm really looking for tuneability and to have it run really well not just ok.

[Nessism]

Get a Dynojet kit and it will run fine with pods.

[schankes]

Thanks, I'll get a jet kit and go from there. Also thanks for all the other sage advice from all the threads on GS Resources!

[Steve]

I was thinking about RS34's ...

Have you talked to anybody about those carbs?

If so, did they by chance mention that you need a bike about TWICE THE SIZE to breathe enough air through them to get them to work right?

Or do you plan on spinning your engine up to about 18,000?

Yes, the BS-series (CV-type) carbs that came on the bike had 32 mm throats, but the slide that is attached to the diaphragm essentially makes it a variable venturi, allowing a larger carb.

.

[schankes]

I spoke with a guy at PJ Motorsports. He was helpful and assured me that if the fit-up was right the carbs would work. That being said I wasn't to keen on ordering a set without getting alot more information. I'm glad that I asked the question here before starting down a path that maybe an expensive trial and error.

[schankes]

Follow-up

Just a quick follow-up. I put a Dynojet kit in last night. The bike runs decent. I need to start fine tuning thing week and get it dialed in. Thanks again for the help and advice.

[tkent02]

Who said it was hard to get a 550 to run well?
Someone who doesn't understand how CV carbs work?

[schankes]

After reading all the posts about keeping the airbox and that the bike would never run as well with PODS I was leary about gong to a dynajet kit. Seems now all I have to do is get busy with the fine adjustments.