GS550E 1981 model

[Bike Extreme]

GS550E 1981 model Hi, I hope their is somebody that can help me. I have recently acquired a GS550E 1981 model in very good condition but the bike had stand a couple of years. Kms on the bike just over 35000.

After I have cleaned the carb fuel system and applied some oil to the cylinders, I have started the bike. Problem was that she battled to start. I have done a compression test on her and found that cylinder 3's compression was only 62psi.

I have opened the bike and found that the rings was no good anymore. The exhaust cam also have quite a lot of wear and tear.

What I have done :

• Honed cylinder sleeves
• Replaced pistons and rings
• New bottom gasket
• New head gasket
• Replaced shims on cylinder 1 & 3
• All my shim gaps are now between 0.001 and 0.004
• Replaced exhaust cam with a good second hand one that I have bought.
• Set valve timing
• Replaced sparkplugs with new ones.
• Replaced oil and oil filter
• Replaced rectifier with a Honda CB900's, because I have had a charging problem
• All head bolts are torqued 2.4 m/kg
• Front and back timing guides were also replaced with new ones

My problem

• Bike do not want to start after everything I have done
• It looks to me that I dont get petrol in my combustion chambers
• I have check the carb again and everything is fine
• It looks like the slides do not lift when I crank the bike

If there is anybody that can help please!

[earlfor]

That bike has CV carbs which lift by vacuum. There is no physical connection between the throttle or choke and the slides. The slides only lift when the engine is running.
have you removed one of the drain plugs in a float bowl to see if any gas comes out?
Have you checked and set the float heights? When you try to start the engine, do you have the petcock set to prime first, to fill the float bowls. Are you using only choke when you try to start the engine. You should not use choke and throttle. It is a use one or the other.

If you can not get any gas to flow into the float bowls, it probably is a petcock problem. Remove the gas line from the petcock and set the petcock to prime (engine not running). Gas should flow by gravity. If you have flow, then set the petcock to run and (engine not running) gas should not flow. Then suck on the petcock vacuum line, this should open the petcock and gas should flow. If you have fuel flow, then it is a carb float level or carb float valve level problem.

[Bike Extreme]

GS550E 1981 Model

Hi Earl,

Thank you for the feed back.

My position is as follows :

• Float levels are set
• Float bowl get petrol. Volume 61 to 64ml bowl 1 to 4
• I don't use the tank, I have a can vertical mounted on a stand that feed petrol with gravity to carb
• I have tried to start with choke open and quarter open no throttle
• I have tried with throttle no choke
• When I only use throttle than it sounds if the bike wants to start, but suddenly it gives one big bang with flame out of exhaust than nothing further.
• I even have tried starter fluid 2 squirts in airbox, nothing

Any suggestions? It is my third old bike that I rebuild so I won't call myself a boffin.

[Nessism]

Sounds like the cam timing is off. I'd double check that.

In case you didn't know, GS bikes won't run for crap without the airbox unless you rejetted the carbs. Not sure if that applies, but it's a common mistake people make.

Good luck

[earlfor]

I'll 2nd about the airbox being a must have.

It apparently is not a lack of fuel problem from your reply. Assuming the valves are set correctly, that would leave valve timing and ignition timing as the most likely fault.
The first thing I would do is remove the valve cover and check the valve timing. The correct cam chain pin count must be directly above the arrows on the cam sprockets and the arrows must be in the 12 o'clock position with the crankshaft at TDC. If valve timing and ignition timing check out OK, then I would suspect a component failure in the ignition system.

[Bike Extreme]

Hi Earl,

Thank you again for the reply. What I have done is the following.

• I have felt with my thumb on the no 1 sparkplug hole and turn the crank till I could feel compression had stop.
• Piston 1 and 4 was on top (1 Left of bike)
• Cam Ex on 1 lobe sharp end to front of bike 90 degree with crank
• Cam In on 1 lobe sharp end to rear of bike 90 degree with crank
• On cam ex 1 with arrow is align with top of head - arrow showing to the rear of bike
• Ex mark is in the 10 o' clock position
• In mark basically the same
• I have counted my timing chain studs L&K screw on Ex to L&K screw on In as 21
• I attach the photos how it look

Please advise.

[Bike Extreme]

Thanks Nessim for your reply. See my response.

[Nessism]

Download factory service manual here...http://members.dslextreme.com/users/bikecliff/

Check cam timing per the manual. For one thing, you need to align the 1-4 T mark on the crank with the indicator, that indicates TDC and is a more reliable method than putting your finger over a spark plug hole.

Good luck.






.

[Bike Extreme]

Hi Nessism,

Your are a life saver! I can see where I have gone wrong! If it was not so cold and late by us 11:26pm I have to my garage and work on the bike.

Thanks again a million. !

[BassCliff]

Greetings and Salutations!!

Hi Mr. Bike Extreme,

You'll find a lot about the care and feeding of a GS in the links below. Old bikes love maintenance. Go through the maintenance lists, properly address every task, and both of you will be happy.

If you are here you probably have a 30 year old motorcycle that needs about 20 years worth of maintenance. In the links below you'll find maintenance lists, documentation, wiring diagrams, "how to" guides, vendor links, tips, tricks, and a whole lot of GS goodness. This is your "mega-welcome". Let's get started.

Let me dump a TON of information on you and share some GS lovin'.

I just stopped by to welcome you to the forum in my own, special way.

If there's anything you'd like to know about the Suzuki GS model bikes, and most others actually, you've come to the right place. There's a lot of knowledge and experience here in the community. Come on in and let me say "HOoooowwwDY!"....

Here is your very own magical, mystical, mythical, mind-expanding "mega-welcome". Please take notice of the "Top 10 Common Issues", "Top 15 Tips For GS Happiness", the Carb Cleanup Series, and the Stator Papers. All of these tasks must be addressed in order to have a safe, reliable machine. This is what NOT to do: Top 10 Newbie Mistakes. Now let me roll out the welcome mat for you...



Please Click Here For Your Mega-Welcome, chock full of tips, suggestions, links to vendors, and other information. Then feel free to visit my little BikeCliff website where I've been collecting the wisdom of this generous community. Don't forget, we like pictures! Not you, your bike!

More links to helpful threads in the forum:
Help! Your Bike Won't Start
DON'T DO THESE THINGS
Help! Your Bike Won't Run Well
Oh God! Pods!


Thanks for joining us. Keep us informed.

Thank you for your indulgence,

BassCliff

[Bike Extreme]

Hi Nessism,

Thank you for the info. I have done everything today. After third push of starter button with full choke, engine had started and purr like a kitten!

I have waited till engine had warmed up properly and closed choke. I have set idling at 1200rpms and she idle beautifull. There are no mechanical noises.

Just one stupid question. When engine idle there is a whoop whoop sound. Is that piston compression?

I owe you a kg of South African game biltong!

Thanks again.

[Bike Extreme]

Hi BassCliff,

Thank you for the hearty welcome! I have found A LOT of usefull information on your site.

I am now finish with the engine and carb. Now it is the rest.

I will report on my advancement. Lovely site! A must for any GS lover!

[Bike Extreme]

Hi,

After 3 weeks is my GS550E 1981 model rebuild finish!

She runs like a dream. Very smooth gear change action. All that I need to do now is wash and polish.

See my photo how she had come out.

Again thanks Nessism, Earl and Basscliff for your input!