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'78 GS 550 Suzuki, all original, 12,000 mile bike

6665 Views 8 Replies 7 Participants Last post by  bettyp

Sometimes something other than a tractor has to have a little work done and this time its an all original '77 or '78 Suzuki GS 550.

I'd picked this up from a local Doctor when he was at the service desk of the local Suzuki dealer asking the cost of repair as it hadn't run in a long time. The estimate was waaaaay over what he wanted to spend, so I struck a deal on the parking lot. I put my son on this particular repair back in '06 and gave it to my son in law for his birthday in '07.

After riding it for three seasons, it developed an issue with the rectifier, so it sat in his workshop for the last 3 years until this weekend. Needing space for a few more woodworking tools and unable to ride for a while, he asked if I'd want it back. Well, heck yeah I'd take it back !!! Pulling the tank and the bank of carbs showed us what E-85 ethanol blend does to old machines. What the heck, I needed something different to work on last Friday anyway !!!!

Pretty much the same thing as a tractor, (except a little different) all you gotta do is keep track of the parts and everything will work out just fine.

Ethanol, having the propensity for drawing moisture caused all the oxidation inside the bowls and main jet castings. Then the evaporating fuel left the typical gummy black and brown varnish in and around virtually all the jets and passages just like on tractors, except there's 4 of them (carbs) on one motorcycle.

Carbs back on, new battery in and charged up, fresh gas in the tank and a lot of tickling on the choke whilst kicking the kickstarter got it sputtering along a bit. Within a few minutes, all four banks settled down and began purring at idle, pulling strong all the way to 8500 rpm's without hesitation. Now all that's left is to balance all four carbs with the mercury filled synchronizer, which is not a task for the ham fisted. Whoops, same picture. Sorry fellas.

Doggone it, this was going to show 12xxx actual miles, but the glare got in the way....bummer. Anyway, sitting on the centerstand, I ran through all six speeds up to 8,500 rpms which should be well over 100 mph without even leaving the shop !!!! Man, I can't wait for warm weather now....Thanks Mike, I'll give it a good home.
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Stinking E85. Ruined my 8N carb and likely my four wheeler as well. Nice looking bike!
E 85, I believe is a very problematic product. There are new motorcycles that are not recommended at all for any percentage. The wife's Mustang's gas tank is full of rust due to it and I carry a spare fuel filter just in case. The last one was plugged solid with rust. It sits all winter in the garage, I guess if it were driven daily all year around it wouldn't have done it. But it has and it is a pain. Thanks for the compliment on the scoot Ernie.
The bike looks great for an antique. :lol: ;) I remember those being real popular around my area when they were new.
From all the problem I hear with "gasohol" and carbs, sure makes me glad I get ethanol free gas from my supplier. ;)
BigDaveinKY said:
The bike looks great for an antique. :lol: ;) I remember those being real popular around my area when they were new.
From all the problem I hear with "gasohol" and carbs, sure makes me glad I get ethanol free gas from my supplier. ;)
I hope you can keep it that way. Hopefully it won't be forced down everyones throat and given no choice...Good to see you out there BigDave.
Haven't seen one of them in a while. Thats a good looking bike. Hate the way the gas treats the carbs I had 2 fourwheelers and a lawn mower do the same thing last year. I found stabil helps a lot with that or at least it seems to with me. Don't know what it does for sure but was told it basically kills the ethonal if that makes sence. I like the bike. When dad sold his 2010 John Deere he bought a 78 CB 750 Honda. We all rode it for years. We've had both Suzuki and Honda's and both were good bikes. You won't see many in the shape yours is in for sure. :) :) Be careful and enjoy the ride. A man needs a few bugs in his teeth every now and then. :D :D :D
hard to believe -what 36 years and counting and still able to rev the engine with that many RPM's. who says older isn't better?
good thing you have the know how to restore engines to their working condition! I use sea-foam in the gas of my tractor, jeep and ATV, seems to do the trick.
Thanks for taking us with you on the bike repair. I think my son had a 350?? Not sure but looked the same. I am not a bike guy but I think I would like a crusier like a Honda Shadow:) Dont tell Cheryl.
My son Adam has one and I think I could putt around on that in the summer. I know crazy talk!
I have 4 sons and 3 of them Have Harleys. The 4 th one had one and sold it.
I just shutter when I see one in you post Wendell . Worry about the boys . One
of the wives also has a Harley. Wendell that one looks well cared for.
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