77 GS550, junkyard dog....

[gerwintown]

Hey dudes,

So I pulled a 77 gs550 out of this junkyard for a pretty good price, it has 7600 miles on it. Had heard the GS series bikes have very strong and durable engines so I thought this would be a great bike to get running.

When I got the bike, the carburettors where being soaked, and I believed it when they told me that the bike had been running when parked.
SO where the hell do I start with this explaining my problem thing, there are alot of problems i think.

Ill give you some information as to what I have done so far that is relevant to my problem(s), in chronological order:
new battery
changed the oil, however with car oil
New spark plugs, and bought the 10 pack in case I fouled one or two
complete tear down of carbs, cleaning off varnish etc with qtips and clearing jets and all passageways with carb cleaner and compressed air.
set float heights to 24mm (+-1)
laser cut all new float gaskets to oem spec and installed them
put back together
set pilot fuel screw to 2 out (have since moved it down to 5/8 with better results)
set idle air screws to 2 out

at this point i reinstalled
the carbs and tried to get her running.
well she would run but terribly erratic
-the 1 and 2 cylinders do not fire until the engine is warm and maybe possible only with choke off
-bog heavily on initial opening of throttle and then would race forward
all of a sudden
-also the engine does not do anything consistently whether cold or warm, its different everytime
-runs rich (if you look at the spark plugs)

i was able to go for a ride on the damn thing a week and a half ago, found out i can only upshift if i use a heavy jerk up with my hand, so mostly riding around the urban area i live in 1st gear, hoping it would eventually loosing some stuff up, who knows right? it will shift but not with the top of my foot. took it up to my college to use the internet to look up my shifting issues, went back out to take it home with the idea that i should get motorcycle oil and that could be the issue. however now i couldnt get it to run at all like i had and if i could get it running and warmed up it would stall out when put into gear. it has been up at school ever since.



so it was then at this point the i recieved my clymer manual in the mail along with a new set of intake boot clamps and clamps for the airbox side as well (they had been missing up until this point
), also i have new o-rings for the intake boots

-i took the carbs off again to check the float chamber and check the jets to see if they were dirty again, all clear and i also finally reset pilot fuel screws to 5/8th out
-this time i made sure the throttle cables were properly adjusted, as i was having issues with that before as well
-started her up and same old crazy crap
-also my battery is now pretty much dead and i am trying to trouble shoot with kick start...im only 24 but man its messing with my knees and hip with all the effort im putting into it
-FINALLY set and tested the timing

started it up and got a damn nice idle a little above 1100 rpms, with the choke on...i would rev on it and while alittle sluggish it was much much better and would rev freely without wanting to die
idled for about 5 minutes and them the rpms started climbing higher and higher and as i took it off choke they yet continued to climb
, gave it throttle which basically killed it.

now it doesnt really want to start, and if it does, it only wants to idle. it will rev but its pretty damn easy to kill with too much. it likes me to kind of jiggle the throttle before i pull it down, it will rev then but die otherwise, if you know what i mean with the jiggling... and at first (after setting timing)
i had all 4 cylinders i am now back to two (3 and 4) and havent gotten it to run long enough to take the choke all the way off.

also a few more issues:
-inherited a damaged and jammed pilot fuel screw on carb #4
----have decided that until i can track down a way to get the jammed tip out and find a new pilot fuel screw (im on to both issues, hopefully can take care of it within the week)
-have not been able to install the orings for the intake boot because i cant the screws off........cant fit an impact wrench in there to do the job i suppose.
-transmission is a whole other issue, i finally put some motorcycle oil and changed the filter as recommended by the dealer and it feels like it wants to change gears easer but of course i havent even tried to take it for a spin yet, but im assuming at this point that i might need to prepare myself for a bent selector shaft and/or bent shifting forks (does this seem like a possibility with only 7600 miles or do you tihnk i got some sludge in the gear box that it making it hard to shift????
-i have ordered an all new vm carb o-ring set from the website recommended on the vm carb rebuild write-up
-i still cant figure out any logical reason for the 1/2 cylinders to not want to run cold...it would make sense to me if it were 1/4 or 2/3....its just wierd, am i missing something?? i have good blue spark from all spark plugs, i know timing is correct
-the dealer said that there would be no reason to expect a need to adjust the valves with so few miles on it, so i have not check valve clearences, nor have i checked compression ( lack tools)


other helpful info maybe:
i am running an inline fuel filter
my gas tank might still be dirty, any tips on how to do clean it? if read how tos but what i cant figure out is how to drain the tank completly, without a little bit of slush left...

overview:
1 and 2 cylinders not firing
bogging on throttle
stalling
dying for unknown reason (like all of a sudden)
stalling out when put under load
engine seems to be ok at first start and then get rougher and rougher as it warms up

im more interested at this point in getting it running before i try to tackle to tranny issues.

next steps:
install intake boot o-rings
install carb o-rings
maybe disassemble the petcock and check the screen above it for blockage and try to figure out how to make my tank spic and span so i can get rid of the inline fuel filter altogether
flush engine with kerosene and then replae oil.

any thoughts on any of this???????

sorry for the scattered presentation of my problems and any spelling errors, i think at this point anything im missing i can just fill you in on later. i hope i am communicating my problem precisely enough

looknig forward to hearing what you all have to say, i am ready and determined to get this right.

thanks,
will

also, will be posting pictures of the bike once i find my camera cable, i have pretty big plans for some customization im going to do to this thing....eventually, and would also like to discuss my ideas when the time comes.

[gerwintown]

ffdf

also, i forgot to mention that everything i have been able to do so far is because of the gs resources and this forum, there is an incredible wealth of information here. the passion and love for these bikes that is evident here has rubbed off on me. i just wanted to thank everybody who has contributed so far before we proceed together.

[robertbarr]

I don't believe you went that far without changing the O-rings -- both the carb & intake boot. That'll eliminate about a zillion variables.

Then make sure you're getting fuel flow TO the carbs. Try to fill a jar with fuel (through your fuel supply line & filter), and see if it takes forever. You mention a dirty tank and an inline filter. Those two combined could mean a clogged filter.

Your carb bowls can fill very slowly while the bike's sitting (with the petcock on Prime). Imagine what happens when your engine uses that fuel faster than your clogged filter can keep up with; your fuel level drops, and sooner or later cylinders start dropping off. That would explain some of your bike's running behavior.

No idea on the trans problem. For the engine, stick with the basics. Your O-rings are already in the mail...

[gustovh]

I wouldn't run Kerosene and then do a flush. If your oil wasn't gooooo when you changed it, you shouldn't need it. You could have a sticky clutch not allowing you to change gears, just a thought. I think that you have so many air leaks and a fuel issue that it will take a little time to sort things out. You can check your fuel valve without taking it out of the tank. Remove the vacuum line at the carb, remove a drain plug from a carb and suck on the vacuum line, hold it for a bit, you should see gas run out the drain.
If your tank is that bad, remove it and remove the valve, drain it completely while sloshing around. Strain the gas through a rag to give you a hint on the crud that you are getting in your gas. If the tank is really rusty, you can do the Kreem thing our use electrolysis to remove the rust, clean with alcohol and fill with gas. If you need to know how to take apart your gas valve, send me a personal and I will send you a pictorial.
Keep at it and keep us posted.
V

[Dave8338]

The classic "lean Burn" condition. Somewhere, you are taking in air that you shouldn't be. Robertbarr is right with the o-rings, that is a must! Also, check all your connections, all clamps, and air box fittings and filter. These all have to be air tight or you will be taking that bike back to wence it came, out of sheer frustration. Also remove the tank and clean it spotless, remove the petcock screen and make sure it is clear, and make sure that your air filter is oiled and greased at the base where it mounts to the airbox.

I would HIGHLY suggest a complete teardown and soak of the carbs and replace all the O-rings!

As far as the upshift issue, it could be a case of stuck plates, weak or broken springs and poor adjustment/sticky cable.

Keep us posted...

[gerwintown]

Yeah, you know when i took apart the carbs last time i had no idea about the oring problem on the intake boots. i was just making sure the passageways and the jets were clear, and the float heights were good. didnt even look at the orings probably. last night after i posted i went to start the bike, this time spraying wd40 in between the cylinder heads and the intake boots. definite air leak there for sure. i always thought it was the lack of clamps that was causing that. when the carbs were apart, the orings looked fine to me, but then upon closer inspection (just looking at an air screw oring) i realize they really do need to be replaced. robert barr, i just ordered a set from you. the carbs are clean now, and when i get the orings i will take them apart again and double...no triple check the cleanliness of everything. once i get those orings for the carbs i will remove the carbs, conduct a complete teardown and rebuild of said carbs, replace intake boot o-rings, and at the same time i will probably test out the petcock and check the cleanliness of the tank.

i think with the exceptiong of the orings on the intake boots i am well sealed from the airbox on, as far as air leaks outside of the carbs.

ive seen worse gas tanks, to be sure. ive jsut been noticing small amounts of crud hear and there. its not caked in rust but its not pristine either.


i should mention im learning everything right now. i have no experience with what i am currently doing. i guess this is all part of the learning curve: when people say you should do something this way, you dont sort of do it this way, you do it exactly THIS way. the thing is ive had rat bikes before and they have never been this finicky, its like "looks good enough" and the thing runs "good enough." this bike doesnt want to do anything. man this thing is good preparation for high maintenance women. although im confident that once i get all this dialed in i wont have much more to worry about it anymore, or at least move on to the next problem.

im still interested in how much i can get away with re:4th carb air fuel screw jammage. i can get a fuel screw from a junk yard, for sure, but im not so sure about getting the old tip out of the carb body. will i need to replace the carb body???

will keep you all updated once i get my parts and get everything installed. i think im on the right track at least, thanks!

Will

[gerwintown]

ok soooooooooo, spent my entire saturday trying to get bottom four screws out of the intake boots so that i can replace the o-rings....one is now stripped badly. cannot reach with vise grips like i could the top 4...cant fit drill or impact wrench into space. dont want to pull the engine just to access 4 lame screws....any ideas??

have replaced all the orings in the carbs except for "F" fuel tube orings...would like to know what the fuel tubes are...haha dont laugh but i would like to know how to do this before i start taking things apart. this is not mentioned in my clymer.

i am also wondering what the marks on the carb bodies right next to each air screw mean. they are at different places (one is at 1oclock another is at 5 for example). should i back out 2 times and then move out or in to the closest mark? do they mean anything?


lastly,
anybody have any extra pilot fuel screws lying around? I need one. I also need insight on how to clear a jammed fuel screw tip out of the orifice made for it in the carb body....i saw a tutorial somewhere long ago but now i cant find it. also, how badly will one jammed and useless pilot fuel screw affect performance...basically, will it affect more than idle?


thanks again,
will

[gerwintown]

dave8338,
will stuck plates release themselves through continued use or do they need to be seperated and or cleaned by hand? would a weak and broken spring be easy (relative to a complete teardown) to replace? anyways i will adjust the cable properly and go from there. thanks.

[robertbarr]

have replaced all the orings in the carbs except for "F" fuel tube orings...would like to know what the fuel tubes are

http://www.thegsresources.com/files/vm_carb_rebuild.pdf

[GS1000S]

You might try heating the screw with a soldering gun or a small gas torch before trying to remove. Another trick is to heat the area around the screw and cool the screw itself with a good penetrating oil before attempting to remove it. Valve lapping compound can give some extra grip in a partially stripped out screw head also. If all else fails cut the head off the screw, remove the boot, and work on the remaining exposed stud after the boot is remove with the method described above.

As for the shift problem:

Make sure your cable adjustment is OK and giving you the right amount of travel to fully disengage the clutch when pulled. If this doesn't fix your clutch will probably have to be disassembled and the steels and the friction discs either cleaned or replaced. I've read where a fine sandpaper(600 grit wet/dry) on a flat surface can be used to clean these up using motor oil for a honing lubricant.

Probably unrelated but I fought a problem on my GS a couple of years ago where the random carbs would intermittently flood and fuel would actually run out of the overflow tubes onto the ground. I can't tell you how many time I pulled and cleaned the carbs and for a while it would be fine. It turned out to be the directional rubber disc in the vacuum petcock which had hardened with ago and was deteriorating and flaking off small rubber chunks that were sticking the needles in the carbs. The petcock is below the tank filter so these small pieces traveled to the carbs.

Good luck. It looks like you bought yourself a real project.

GS1000S

[quote=gerwintown;636395]ok soooooooooo, spent my entire saturday trying to get bottom four screws out of the intake boots so that i can replace the o-rings....one is now stripped badly. cannot reach with vise grips like i could the top 4...cant fit drill or impact wrench into space. dont want to pull the engine just to access 4 lame screws....any ideas??

[relic-rider]

If you alreadt have one screw out of each intake flange, just tap the whole flange with a piece of wood in a counter clockwise direction. The movement of the entire flange is usually enough to loosen the screws. Then get some allen head bolts to replace those goofy phillips head ones.

[gerwintown]

hmmm, ok i hadnt tried that....that sounds like a pretty good idea, or at least better than drilling off the heads. im gonna try that out right now.

[gerwintown]

relic-rider.....total lifesaver man! worked like a charm, couldnt have been easier! thanks dude.

so with that I went ahead and progessed to replace the o-rings and reinstall the boots and carbs. oiled the air filter and the rubber seals inside the airbox and manifold thing.

set the fuel screw to 5/8 turns out, set the air screw to 2 turns out for starters.

with the choke on, i started it with the kickstart on 2 kicks. was idleing sort of rough, didnt like to rev and slowly decided it didnt want to rev at all as it got warmed up. was running on the 3 and 4 cylinders only.

i was like you gotta be kidding me....basically the same problem as before.

however now i knew that there was a seperate plate to adjust for the timing of the 2-3 points and went ahead and found that it was off by a millimeter, fixed it. fired it up, same problems.

at this point i could still only get it to idle, and only with the choke on. with a good blip of the throttle it would die and refuse to start for a while. decided i was flooding it and decided to adjust the air screws out further. while idling, i set the 3 and 4 carbs to 3 turns out first, idle evened out a little bit and i was able to get it to rev, however with some bogging. went over to the left side and with my right hand behind the left exhaust started turning with my left hand the air screw on the #1 carb out to three....started to feel a few pops of heat on my hand, im like hell yeah and continued to 3.5 turns out and once i had done the same on the #2 carb i had a nice, hot, steady flow of exhaust coming out of both pipes.

now i can take it off the choke and it revs pretty damn smooth if i must say so myself....totally ecstatic about the nice running engine ive finally managed to achieve. im sure i could spend a little more time dialing it in more, ive got to adjust the idle speed screw (throttle stop) a little bit more...but this is absolutely the best its run since ive had it in my possesion, and im pretty damn happy right now. of course well see if it cooperates the same way this weekend.


havent taken it for a ride as ive misplaced my tire pressure gauge and want to check tire pressure first. plus i havent really gone over the whole bike and checked every crucial bolt to make sure it is tight...you know, carb problems i can deal with, wheels flying off my bike at 35 mph is NOT. and it got dark... so this weekend i will properly adjust the clutch cable, check all the bolts, inflate my tires and i will finally be able to go on a spin and see what this bike is all about.

hopefully the clutch cable adjustment works out, and hopefully the clutch assembly breaks free of any crud or whatever once it gets hot and moving. if not, im afraid to say this thing is going to have to be parked for 3 more weeks until school is out and i am able to take out/examine/clean/replace????? the clutch assembly and or do whatever the hell else i can do during my 2 week break (and inbetween fishing trips of course). but hell at least im that much closer to having this thing ridable, havent spent my 1000 dollar ceiling (not including the many cosmetic/aesthetic improvements ive got planned) yet either...so so far so good.


honestly guys, if it werent for this site i never would have gotten this thing to work, i would have given up on it weeks ago. this place is great. cheers to the internet and helpful, knowledgeable people.

of course ill keep you guys updated, and ill definitly be back for more help in a very short term. thanks!

Will

[robertbarr]

hopefully the clutch cable adjustment works out, and hopefully the clutch assembly breaks free of any crud or whatever once it gets hot and moving.

Even if your clutch assembly is stuck, it's a simple process to deal with. Compared with the carb work you've just managed, it's nothing. Just get an impact driver, remove the cover and start unstacking the drive/driven plates.

2% as involved as carb work.

[gerwintown]

...and honestly it wasn't really all that bad....the carb work that is, although interestingly enough before i bought the bike i thought carb work was the easiest part....wouldnt have been as bad if i weren't also taking 15 credit hrs for school, its just finding time that is difficult really. its cool now because i feel i could do anything with this machine so long as i do it right and take my time.

i just want to get this thing ridable before i start fabricating appearance and weight saving mods....