DESPERAT CRY FOR HELP!! Calling all GS500 Experts

[lopee]

Have you replacer the plug wires ? My problem was the same, right side, and i thought my right side carb had a too large of a seat for the air/feul mix screw. after about 8 months. tested the interference on the wires, was in spec but high interference, so i changed to accell 8.0 mm wire. works great for a $10 fix

[liquid0715]

Bassmechanisz,
Located in Fariview, NJ.  Your about an hour away from me.  Wanna go for a long ride?   

Lopee,
I will switch the coils today.  If the problem switches sides then I am replacing the coils & wires.  Just not worth the headache.

I will let everyone know of the progress after switching sides on the coils.  My thinking process after all your help is that if the problem switches sides then I know it is electrical. 

JeremyNash & Chanse mentioned the pickup coils.  If I switch sides on the coils but the pickup coils are defective the problem will still continue on the right side correct?  Is there a quick way to tell if the pickup coils are shot?

By the way this gas fouling (dry) not oil fouling, for those of you still interested.

Thanks,

[bigfatcat]

BigfatCat

Once the plug fouls you can tell the bike does not want to move below 4k RPMs.  Once I'm over 4K it really does not matter whether the plug is fouled or not.  But initially with a brand new plug the bike moves.  After a couple of miles of riding the bike feels like its bogging below 4K when you hit the throttle, say from a complete stop.

I've seen similar in small car motors with crappy wires, arcing ignition switch, etc ... long as you keep the revs way up you can keep going;  let the revs fall and a cylinder or two will stop firing ...

btw, if swapping the coils/wires yields no change, then you could still have an electrical fault 'upstream' of the right coil so that it's not firing at full voltage or intermittently .  Trigger/pulse coils, ignition control unit, the wiring/connectors in between ... somewhere

[liquid0715]

I just got done swapping the coils and takin it for a ride.
Same crap!!

It felt like it was running better but I must of not rode far enough.  Needless to say a brand new spark plug was black as coffee after 2 miles of riding.
I checked the pick up coil and that whole section looked practically brand new.  I checked all the relays I could get my hands on and they looked good for the most part.  No rust, burns or anything.
Does this mean at this point it is not electrical?  I want to get something out of this experiment.

I could not perform the float bowl check tonight, the tube I got was too large in diameter. 

[lopee]

Man, Look. The spark wires twist right out of the caps and coils, so CHECK THEM. coils are probably fine. why not try it ? the wires might need to be tightened or replaced but can be done in 10 minuets for less than $20. Any 8.0 mm copper-core wire will work, Accell is what i used. If it doesnt work, you spent only $20, but i believe this is it. I HAD THE SAME PROBLEM for months thinking it was the carb. Not enough spark from restricted flow through spark-wires = Rich condition.

[bigfatcat]

I just got done swapping the coils and takin it for a ride.
Same crap!!

It felt like it was running better but I must of not rode far enough.  Needless to say a brand new spark plug was black as coffee after 2 miles of riding.
I checked the pick up coil and that whole section looked practically brand new.  I checked all the relays I could get my hands on and they looked good for the most part.  No rust, burns or anything.
Does this mean at this point it is not electrical?  I want to get something out of this experiment.

I could not perform the float bowl check tonight, the tube I got was too large in diameter. 

Just looking and fingering stuff isn't good enough - especially eletrical components.

Assuming the shop did a thorough job on the carbs; assuming right carb was not mal-adjusted by said shop :

Me, I'd start with what lopee says, replace plug wire, then start replacing electrical stuff leading to the right coil.

BUT, since you aren't mechanically experienced, I'd suggest taking it somewhere to have a thorough electrical system test done. (altho you ccould probably handle lopee's suggested fix ...)

btw, how old is your bike. ?

To be honest I haven't had any problems with my '95 so haven't really gotten into it - but I've seen this type failure on cars .

[joshr08]

did the shop say if your jets are stock type or if you have a dynajet kit?

[bill14224]

I agree with lopee.  It could very well be a corroded ignition wire end.  After all, the bike is 17 years old.  Are the wires original?  I bet they are.  If you have enough slack just unscrew it and trim a little off the ends and put it back on.

Or, you can continue poking it with a stick, getting nowhere.

[joshr08]

bill you are alive
havent seen you in forever

[liquid0715]

Cant be the plug wires.  I didnt know the wires and plugs can be separated until I read your responses but when I did the swap last night, I exchanged the right plugs and wires to the left and the left to the right.
If it was the plug wires the problem should have swtiched sides which is what I was hoping for.

[liquid0715]

OK!  Thanks to much appreciated efforts of BUDDHA, my carbs are synced, clean and adjusted.  I am still fouling on the right side.
It only tends to happen when I ride not when it is idling.  Any suggestions?  At the moment I have partially fouled carbs that have maybe 20 miles on them and if I can start the bike it runs on one cylinder.  If I put brand new spark plugs then everything is fine for the moment but as soon as I go for a ride then the right side fouls after approximately 2-3 miles. 

BUddha suggested I talk to starwalt or someone who knows electricals.  I will test out the compression on the cylinders, although the bike shop near me told me the compressions is good.  I just want to test it out myself and give you guys the results.  I just need to modify the compression tester so I can test.

Then I will bring a multimeter to test out the electrical system.  At this point, I want to fix it for the principal and because I love the bike.

So Any ideas? ANy questions?

[ohgood]

OK!  Thanks to much appreciated efforts of BUDDHA, my carbs are synced, clean and adjusted.  I am still fouling on the right side.
It only tends to happen when I ride not when it is idling.  Any suggestions?  At the moment I have partially fouled carbs that have maybe 20 miles on them and if I can start the bike it runs on one cylinder.  If I put brand new spark plugs then everything is fine for the moment but as soon as I go for a ride then the right side fouls after approximately 2-3 miles. 

BUddha suggested I talk to starwalt or someone who knows electricals.  I will test out the compression on the cylinders, although the bike shop near me told me the compressions is good.  I just want to test it out myself and give you guys the results.  I just need to modify the compression tester so I can test.

Then I will bring a multimeter to test out the electrical system.  At this point, I want to fix it for the principal and because I love the bike.

So Any ideas? ANy questions?

stuff you can do without getting dirty:

check float height
check for good spark (pull plug, start with it touching some metal piece, look for BRIGHT BLUE spark)
check air mixture screw position
check for oil in your cylinder (warm up the bike, then pull a plug AND  WIRE (letting it ground on the frame so you don't destroy things) and replace it with an oid plug... start for a 20 seconds or so... then swab the cylinder / piston for oil. oil means you have sealing issues.


stuff you can do with a little dirty ness:

pull the vaccum caps, and check your needles are in right, along with smooth slides, make sure the needles are STOCK and not dyno-crap. stock needles have a fat, constant taper. dyno-crap are skinny like a crack hoe and have two tapers. dyno-crap means throw them away and get stock.

pull the vacuum caps and make sure you have: needle + needle doughnut, clip, washer, spacer and that tiny washer on the bottom of everything. anything more and you've found your problem.

pull the vaccum caps and look for your oring under the cap. if it's skinny or cracked, replace it.

pull your vaccuum caps and check your boots. if there is a hairline crack, toss it.

pull your vaccuum caps and check for cracks in the CAP.

yes, i know what some of your are thinking now... he has a RICH condition, but all these things are checking for LEAN... ya, i know. whatever. they may be so far out of adjustment other things are going unnoticed.

things that you can do if you get really dirty:

pull all the connectors and make sure there is no corrosion.
compression test.
valve check/adjust (i doubt your shop actually did it, sorry)
is your boot (intake pipe) on the LEFT side carb good ? are you sure ? have you tugged on it while the bike is running ? those things are thick and rubber, but a crack is hard to find.

have you checked your T where the fuel lines go into both carbs ? the left side carb may be getting some air there... causing  the RIGHT to look like it's the problem.

lastly, take 10 giant steps back, and let a friend look at it. take 3 days off, only think about things positive, and that you haven't tried. dive in again.

good luck. carbs suck. yours just suck more than anyone elses right now.... or maybe they're fine, and you have bigger fish to fry. good luck anyway.

[liquid0715]

OK!
As per instructions from Buddha, I am posting this on the board.  Buddha has been helping me along with this problem for weeks.  My lack of knowledge about bikes is not helping.  I am mechanically handy but just afraid to work on something I know nothing about. 

After several weeks, here is quick summary. 
At this point the bike runs, likes it when I run it hard.
110psi compression on both cylinders when engine is cold.
COuldnt get an accurate reading from hot engine as I still am working on a solid adapter for the plug entrance with my tester.
The right side plug is fouling instantly on the bike.
The carbs have been overhauled by BUddha, 150 jets, Lunchbox K & N with stock exhaust.  Working on aftermarket exhaust but that is the least of my worries at the moment.  '94 w/ 19,000 miles.

Tnight while trying to test the compression again and waiting for the bike to warm up, I noticed that the left cylinder sounds different than right. 
The left sounds good while there it sounds like something is loose on the right.  Very very faint but it is there.  Only could be heard when idling.
If idled for long, if I gently blip the throttle the bike stalls.  Did this consistantly twice.  If I rev it past 6K rpm the bike comes to idle fine and will not stall again unless I let it idle for 5 minutes and try to blip the throttle.  Not sure if this is related to anything but just throwing it out there.

I thought maybe the intake valve was staying open slightly, thinking a constant fuel leak but BUddha suggested that would make it run really reallly lean. 
I was told in the begining of the season by the bike shop that the valve timing is good along with the compression. 

Buddha is suggesting Piston slap for the noise I am hearing.  That sounds really really bad to me.
Does this tie in with the plug fouling on the right side or is my paranoya getting the best of me?

[liquid0715]

check for oil in your cylinder (warm up the bike, then pull a plug AND  WIRE (letting it ground on the frame so you don't destroy things) and replace it with an oid plug... start for a 20 seconds or so... then swab the cylinder / piston for oil. oil means you have sealing issues.

I would like to do this but I need to understand it further before attempt.

So take out the plug wire and let it run on one cylinder and then check to see if there is oil on the bad cylinder?

When I look at pictures of wet fouling versus dry fouling mine definitely looks like the dry fouling.  And as hard as it is to believe I have not noticed any oil consumption when I check the oil.

[liquid0715]

bump

[liquid0715]

This is to annoying.  Same problem for 2 years.  This is ridiculous.  No bike shops around here take my bike seriously.  Everytime I take the bike to them I either get them telling me to get a new bike or they cant figure out what the problem is.  Having said all that to summarize 2 years here is goes.

Bike has an open K & N filter setup.  Aftermarket exhaust, new mixture screws for the carbs, Carbs have been rejetted by buddha. 

After changing the stock exhaust to aftermarket, synching the carbs, and putting new mix screws, the right side plug still fouls but the severe effect really isnt noticeable when riding until after 50 miles or so.  Before all the changes, the plug would foul so bad that I would hardly make a 10 mile ride.

So the exhaust, carb synching and new mix screws helped tremendously but didnt solve the problem.  The engine compresion is good and even on both sides. 
So can anyone help me in person, willing to pay if the problem is resolved.  I live around George Washington bridge.  WIlling to drive to you but it would have to be less than 50 miles.?

Can the plug fouling at this point be caused by left over carbon deposits from the past???

I dont want to sell this bike to make it someone else's problem.....I wouldnt be able to get any sleep...

[sledge]

What shape are the valve guides in?

[liquid0715]

valve guides are the holes the needle travels up & down in?  If so, I didnt visually see anything wrong with them.  Do they need to be replaced every so often?

[The Buddha]

I would bet its the carb. Valve guide is the metal sleeve the valves open and close in.
PM me and I'd send you a phone number, this weekend i'd help you trouble shoot it.
Cool.
Buddha.

[lopee]

DID YOU REPLACE THE PLUG WIRES? IF NOT CHECK THE SPEC ON THEM. MINE DID THE SAME ON THE RIGHT. MEASURED THE INTERFERENCE AND IT WAS OUT OF SPEC ON BOTH, BUT ONLY HAD PROBS ON THE RIGHT. CHECK THEM OR REPLACE THEM, 10 MIN OR 10 DOLLARS