GS550T Refresh

[camodro]

At the end of the 2020 riding season, I noticed my GS550T was not running as well as it had previously. So over the winter I decided to go through the carbs, expecting that something had gotten gummed up from ethanol in the fuel. While I didn't go through the carbs completely, I thought I had cleaned things out pretty well, what with removing and cleaning the jets, etc. Then life got in the way and I wasn't able to come back to it till earlier this year. Got the carbs back on the bike and expected to have to do a little twiddling. Unfortunately the bike will barely run now. I can keep it running around 1,000 rpm with full choke, but if I try to give it the least amount of throttle or reduce the choke it instantly dies. So I'm guessing that I need to do a real carb teardown and refresh (using the guide this time and a set of o-rings from Nessism). I also plan to check and adjust the valve clearances, and thoroughly check the stator and r/r. Are there any other procedures that any of you would recommend?

[Nessism]

Check my signature for the newbie mistakes thread, carb rebuild thread, and a link to fresh O-rings.

If you can't see my signature, be sure that "view signatures" is turned ON, in your forum profile.

While our GS bikes are some of the best ever made, they are 45 years old now, and need some love in order to keep them running well.

Good luck with your project!

BTW, here is a photo of my old 550T. Great bike!

Picture136 by nessism, on Flickr

[camodro]

Thanks Ed. I just got the o-rings in the mail today (thanks again) and am planning on using this forum extensively to keep my GS going.

[scratch]

5 years is plenty long enough for critters to get into and build a home in your airbox... just in case you haven't looked. Had a whole mouse colony move in one year, think they turned the carb throats into a latrine, good times.

[camodro]

Thanks Scratch. Already looked in the airbox. No critters in there, but I do plan on using my smoke generator to spot any leaks in the airbox/intake plenum. I have a sneaking suspicion that she's sucking in lots more air than what's good for her.

[camodro]

[rphillips]

Looked good for that 2020 picture, hope still near that way...

[camodro]

Yeah, she's still a looker. Just a little dusty.

[camodro]

Also curious about something I hadn’t heard till I joined this forum: what are the benefits of swapping a head from a 650 onto a 550 engine? Is it really worth the headaches?

[Grimly]

Also curious about something I hadn’t heard till I joined this forum: what are the benefits of swapping a head from a 650 onto a 550 engine? Is it really worth the headaches?

Head and barrels? Yes, it's been done and made to work quite well by all accounts.
I don't know the details, though. Not my bikes of interest.

[camodro]

Thanks Grimly. I dug a little deeper. Basically ups the displacement to that of the 650 model (I guess it ends up being 673cc) and gives you the updated combustion chamber while keeping the bottom end/crank/roller bearings. So basically a slight performance upgrade. I think I'll stick with my original gear. It serves me just fine.