HI ALL!
I bought my bike last year and am a beginner rider and owner. Currently, my bike is going through the right cylinder spark plug like a 1 year old goes through pampers. The bike is at a professional shop for the last 2 weeks and they can not figure out what the problem is. The bike has an open K & N filter setup and bigger jets than stock. The carbs are clean, the valves just got readjusted and my bike is still managing to foul the right spark plug. The left side is fine. I foul the plug in less than 5 miles.
The shop suspected the choke getting stuck, that was not it.
Checked out the carb, everything was good. They noticed the carb had 2 different size mixing screws when they first got it but replaced the screw with a matching correct size. The wires are okay.
They are stumped and I am just frustrated. I searched for similar topics on the forum and all of the suggestions that were made have already been checked out according to the shop. The float bowl heights are correct.
This is either a very stupid problem that everyone is overseeing or its complicated enough where the only person that would know the answer would be someone that experienced the problem.
A lot of people on the forum seem to have the left cylinder fouling but mine is the right side. I do not know anything about bikes so PLEASE HELP so I can go out and ride whats left of the almost over summer.
more info on the bike would help year. mileage. coil taking a sh!t? have they done a compression test?
1992 gs500, about 19,000 miles.
Compression test was good.
Coils are good. That was the first thing I can think of was no spark.
Quote from: liquid0715 on August 12, 2009, 04:07:36 PM
The bike is at a professional shop for the last 2 weeks and they can not figure out what the problem is.
Not a very "professional shop" then... Take it somewhere else :thumb: I couldnt imagine someone Im paying and trusting to fix my bike telling me... We dont know what it is... ??? :cookoo:
I can not disagree but they have been very nice and patient with my needs ever since I got the bike.
They are puzzled themselves, and havent asked for a dime yet for this problem.
it has to be a carb set super rich or an intake valve stuck open to foul a plug that fast if its getting good spark
How do you (they) know the wire is 'ok' ?
A weak / intermittent spark can let a plug foul, making you think you've got carb/oil fouling problems.
Is your bike down on power ?
I'd look to the ignition circuit 'cuz seems like everything else has been covered.
Joshr08,
How is a carb set too rich? do you mean larger jets? different mixing screws?
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.
different jet/bad diaphram in the top of the carb/needle set different/air mix screw set wrong/ not synced right
I am guessing all of those things you mentioned can easily be spotted at a professional motorcycle shop with just the carbs in their hand to play with?
I know I wont be able to tell unless I am guided step by step.
Does the gas I put in make a difference? I have been using 87 octane. Although if gas was the problem iit would be fouling on both cylinders. The one cylinder is the key here. The left side is fine, the right side is not, so I guess something has to be different than the left.
What can really be different on the right cylinder/carb that a motorcycle shop might overlook? Can I exchange the coils to see if the problem switches sides?
yes coils can be swapped to see if it changes sides or stays the same
Plan A: Sell it with new plugs....JK Plan B: I would certainly agree that you have a carburetion problem. I ,personally, would just rebuild the carbs and inspect/rejet them as per the recommendations laid out in the wiki and see what happens. It's definitely not gonna hurt, lol.
I had a problem with carbs fouling out after maybe an hours time on them due to the tank liner dissolving in the gasoline. changed tanks, problem went away.but that was on both cylinders, so shouldn't be your problem. I would swap coils, and see if the problem moves with it, if it does, then you've found your problem
THanks everyone for the ideas. Keepin Comin :icon_lol:
As I was writing on here is when I thought about exchanging the coils. The carb was worked on so much I feel like the problem can not be there even though everything points in that direction. I think they tested the coils and they got spark and moved on but i dont think anyone tested to see if it was consistent.
HOw does the coils work in the GS500? Is there a timer that sends the spark every so many seconds. I mean in a car it is the distributor cap that controls the spark and timing. All we have are two coils, what controls the timing?
there are pickup coils under the cover on the right side of the bike.
crash history? right low side? broke loose a pick up? it would only have to be off a few milimeters to deminish the spark.... Oil fouling plug, or gas? I know you said the wires are ok but how old are they. I have seen "ok wires" in a car look good and have no significant damage, but turn the lights off and watch the sparks jump right out of the wires. Crazy little light show. umm. I'm also leaning to jet size for some reason. What is your bike jetted at? What is the set up on the bike K&N replacement or lunch box, Jet size ?, Stock, after market, or stock modified (slip on)? +1 on the swap coils check.... and the gas should not matter the manual just states "87 to 91 octane". so any of the three would be fine. Thats all I can think about right now. Been up since midnight at work... ITS FRIDAY BABY. YEAH.......
THe history of the bike is a problem. I do not have it.
When I purchased it 2 years ago it wasnt running. Mainly due to dirty carbs & a bad tank.
Had the shop clean the carbs and Buddha sent me a used coated tank. Any problems due to the tank would result on both cylinders fouling.
I do not know the jet sizes, all I know is they are larger than the stock ones. I have a K & N setup that came with the bike, straight K & N on the carbs, I believe the "lunch box" setup.
Stock exhaust. I can find out the jet sizes from the shop.
When the shops said they have looked at your carbs ask them if they pulled them apart fully? A shop where I USE to take my bike say they have cleaned the carbs but all they do is spray a can of carby clean down the throat. For a shop to fully strip down your carbs will cost you a packet (do it yourself if you are able and mech inclined).
It will not hurt to take the bike to a different shop regardless of how patient and nice your local is. Is strange such a simple engine configuration has a pro bike shop stumped when they deal with complex EFI engines every day.
keep us informed, good luck :thumb:
Quote from: bigfatcat on August 12, 2009, 04:56:06 PM
How do you (they) know the wire is 'ok' ?
A weak / intermittent spark can let a plug foul, making you think you've got carb/oil fouling problems.
Is your bike down on power ?
I'd look to the ignition circuit 'cuz seems like everything else has been covered.
+!
Just out of curiousity where are you located as someone on this board might be local to you and be able to offer better advice actually seeing the bike first hand and help you learn about it at the same time.
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
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,
Quote from: liquid0715 on August 12, 2009, 05:02:36 PM
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
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.
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.
Quote from: liquid0715 on August 13, 2009, 07:00:59 PM
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 .
did the shop say if your jets are stock type or if you have a dynajet kit?
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.
bill you are alive
havent seen you in forever
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.
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?
Quote from: liquid0715 on September 07, 2009, 12:02:03 PM
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. :)
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?
Quotecheck 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.
bump :tongue2:
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...
What shape are the valve guides in?
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?
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.
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
Buddha,
I will send you a PM.
Lopee,
Where do you recommend I purchase the plugs? Autozone, Advance Auto type place? Any recommendations on brand or size? Any place on the internet?
Thanks,