Motorcycle Forum banner
1 - 9 of 9 Posts

·
Registered
Joined
·
3 Posts
Discussion Starter · #1 ·
I recently bought a 1980 suzuki gs550e that seemed to run and drive great. The day after I bought it it fired up perfectly that morning, played a bit, then let it sit for a few hrs while doing other stuff. After a few hrs I went to ride it again and no start. It would cough but not actually fire. Tried having battery charger on it to make sure battery wasnt problem no change. Filled it with 91oct gas and put seafoam in the tank as the tank was fairly low. No change. I pulled the fuel lines off and found that with the main line disconnected the vaccum line does pull fuel from the tank. The main line however seems to be clogged to blow through it. I blew through the vent line which then freed up the main line. Bike fired right up ran a bit rough at first then smoothed out and rode fine. I have to do this everytime I want to start it. The lever on the petcock is broken off so I cant do anything with it, am pulling a part number from it today to get a new one. Once the bike is god and hot it wants to idle just above 3k rpm which seems like a lot and doesnt seem happy there. Any suggestions? Thank you
 

·
Registered
Joined
·
403 Posts
you will find a service manual here: (http://members.dslextreme.com/users/bikecliff/) center column. There are great carburetor rebuild tutorials there also and you will need to do that. Those bikes were designed for regular pump gas, you are wasting your money on anything else. It is what I run in my GS1000E. Your motor is a baby 1000. Not sure about your petcock but you will Probably find one at Z1 enterprises.
 

·
Registered
Joined
·
3 Posts
Discussion Starter · #3 ·
I've always been in the understanding that pre 90s stuff should run non ethanol fuel, hence the reason I put 91 because the reg 87 has ethanol. I did find that if I start it at half throttle it seems to like that. Im thinking its flooding itself while sitting. New petcock is on its way. I'd rather not rebuild the carbs on this I've heard a lot of horror stories but if necessary ill dive down that. Thankyou for the resource so I can read up on the bike that will very helpful as I start messing with it more.
 

·
Registered
Joined
·
403 Posts
StarTron in your fuel takes care of the alcohol forming a gel when it sits for a long time. Carburetor rebuild is no problem if you follow the tutorials and not skip any steps. Carburetor kits cause most of the horror stories, those parts can not touch the quality of factory parts and there are very few of the factory parts that can't be cleaned and reused. The factory parts that you would most likely need in rare instances are still available. The web site I gave you has a new rebuild tutorial for the BS (CV) carburetors that is excellent. You can download and print any of the content. I started out knowing nothing about the carburetors and learned through the tutorials.
 

·
Ace Tuner
Joined
·
4,352 Posts
I put 91 because the reg 87 has ethanol
Good move.
We are forced-ish to use ethanol fuel in my area. That stuff is a carburetor killer.
There is only one station fairly close by that now sells ethanol free gasoline where I live.
It costs around $1.50 MORE per gallon but it's worth every penny. The difference is like that of night and day. My bike balks if I let it sit for as little a two weeks with ethanol fuel in the carbs. With ethanol free fuel, no problem.

S F
 

·
American Legion Rider Staff Administrator
Joined
·
27,445 Posts
The difference is like that of night and day.
I have a riding buddy on a Sportster that was having nothing but problems with the way his bike ran. So I asked where he was getting his fuel which he said the nearest station with the cheapest gas price. I suggested he ride a little further and just try using the fuel I get that costs way too much. He did and suddenly all his bike problems vanished. He's been using the REAL gas since. That ethanol **** should be outlawed. Or put a moonshine label on it and sell it at the liquor store.
 
  • Like
Reactions: afixcat

·
Retired twice: Navy and as a govt contractor
Joined
·
15,917 Posts
You used to be able to get real gas at marinas only around here. Boy did they look at you funny when you rode down the pier. Now even the marina's have ethanol
 

·
Registered
Joined
·
3 Posts
Discussion Starter · #8 ·
StarTron in your fuel takes care of the alcohol forming a gel when it sits for a long time. Carburetor rebuild is no problem if you follow the tutorials and not skip any steps. Carburetor kits cause most of the horror stories, those parts can not touch the quality of factory parts and there are very few of the factory parts that can't be cleaned and reused. The factory parts that you would most likely need in rare instances are still available. The web site I gave you has a new rebuild tutorial for the BS (CV) carburetors that is excellent. You can download and print any of the content. I started out knowing nothing about the carburetors and learned through the tutorials.
I've rebuilt Rochester carbs for boats and cars so I have the basic knowledge of how they work. Just the tuning of all 4 is what has be worried. What in particular do you think has failed in the carbs?
 

·
Registered
Joined
·
403 Posts
Wait until you get them broken down and in carburetor dip and you will see the years of crud in the tiny passages melt away turning the dip brown. I rebuilt a set on a friends 550. He said he rebuilt them and they looked like you could eat off them, but the second I put them in the dip brown started boiling out of them. After 24 hrs the clear dip was dark brown. They worked the second time around. The tutorial will get you in the ball park to start the bike then you can refine the tune and then a manometer will be necessary to sync all four so each cylinder is making the same power. I use a Carbtune Pro manometer. Nice thing about it is there is no glass or mercury to break if it somehow gets dropped. I have used the carburetor dip from Napa and it does a nice job if you allow them to soak for 24 hrs. Also, a bad petcock can cause all sorts of bad behavior. Unobstructed fuel flow in a gravity system is very important. I got tired of the Suzuki petcocks and got a Pingel petcock. you can definitely tell the difference in the way the bike runs with a high flow petcock. The only problem is training myself to turn it off when I stop. I have ridden many years with vacuum petcocks. Do not put an external fuel filter on the fuel line, they are always trouble on these bikes. A clean fuel tank and the petcock screen is all you need. I hope no one tried to reline the fuel tank and yours is clean of rust. Mine was so bad I had to give up the skunk tank and buy a NOS '80 tank.
 
1 - 9 of 9 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top