Need HELP With New Bike!!!

[JChivell]

Ok.... So, I just bought a 92 GS500 and I was really excited. This is my second bike. My first bike was a 76 Kawasaki KZ400 which was in a million parts and I used it to learn how to ride/repair.

So I have this new bike and this is what happens:
It will idle beautifully, but when you open the throttle the engine dies.
I replaced the air filter because it was disgusting, the fuel lines, the spark plugs and put some seafoam in the tank.
It would run, but you would have to be REALLY gentle with the throttle. Sometimes it would just kick in and start jamming down the street, but it was really off and on.
I took the carbs off and they looked fine. I cleaned them a little, but they werent too bad at all.
While it was idling one day I noticed that the cylinder on the right (if you are sitting on it) wasnt getting hot at all. I figured either the carb wasnt putting out the right amount of gas, or the plug wasnt sparking. (I didnt test compression yet)
I charged the battery one night because it was getting low on charge and wouldnt start.
Put the battery back in....and it still wont start. Everything else works fine(lights, turn signals, horn), but the bike just wont start.

So thats where Im at. It wont ignite. Theres no clicking. Its in neutral. Pull the clutch. Push the ignition button. Nothing happens

I also noticed that the bike wont shift into any gears while sitting there. If i turn the tire, I can get it to drop to 1st, but thats it. Once in first, I cant turn the tire at all.....

I just dont know. This bike was "supposedly" taken well care of. It has about 18k miles on it.

PLEASE help me. Where do I go from here?

I had a clymer for my old bike, but got a haynes for this one.... there doesnt seem to be a diagnostic section in the manual, so Im kinda stuck.....really stuck actually.

[DoD#i]

First things first - and do try to be careful about terminology, it just confuses things when you call the starter button the ignition button, and not cranking (which is what you seem to be describing - starter motor does not spin, motor does not turn over) with not igniting (a very different problem - no spark).

Ignoring the issues you started with (poor running, right cylinder not firing at least some of the time) let's see if we can at least get you to where you can work on those problems by being able to start the bike again.

Simple diagnostics for no crank, with lights, horn, etc all working.

Pull the rear plastics. Remove the rubber cover on the wires at the starter relay. Put the bike on the centerstand, in neutral, ignition (key) on, choke on, clutch in. Use a wrench to short the big terminals of the starter relay (unlike a car battery, a bike battery is very unlikely to weld the wrench to the terminals). I've personally used this technique.

If the engine cranks, you have a few things to check. If the engine does not crank, you have a few other things.

The bar-none commonest problem if the engine cranks (when you short the relay) is a bad clutch switch, or bad clutch switch wiring. The engine can start and stay running if that is what's wrong. Pull the headlight out, get into the wiring, identify the clutch switch, disconnect it, connect the two things that were connected to it to each other, try starter button again. If that works, you can replace the clutch switch at your convenience. Less likely but possible is the sidestand switch - if that is bad the engine will not start or run (that one engages the kill system). A bad starter relay is also possible, but not very common.

I'm less familiar with problems where the engine would not crank (when the relay is shorted), but they would be along the lines of bad electrical connections to the starter motor, a bad starter motor, a frozen engine, a totally hydro-locked (cylinder full of liquid gas) engine, a dead battery, etc. You might also have a condition where you hear a high-pitched whine - that's the starter motor spinning but the starter clutch not working - check /search the board for how to fix that one, it's documented.

If you you want to fiddle with turning it over by hand on the centerstand, take out both spark plugs so that you are not fighting compression, and shift UP into second, not down into first (and if you can get things to move so you can keep shifting, turning it over with the wheel gets easier as you shift it up to sixth.) The wheel is much better/safer than putting a wrench on the crankshaft bolt.

[JChivell]

Thanks for your help, and sorry for my poor terminology.

I shorted the relay and the bike started. It took a while, I had to put it in the PRI position, but I got it running.

So, it worked fine for a while, rode it about 12 miles. On my way back home the engine started hiccuping. I dont know how to describe it really, but it was like it would just shut off if it idled below 2k rpm (as if the engine didnt have enough momentum to keep running...). Finally while driving it, it just cut out completely. I pulled in the clutch and tried to downshift and pop it into a lower gear but nothing happened.

I let it rest for a minute or two, took the cables going to the spark plugs off and put them back on again. It worked a whole lot better.

At this point, Im not really sure whats going on. It runs consistently, but not well and Im almost positive the right cylinder isnt working right. I will do a spark check when I get the chance. Is there anything else I should do? I feel like the engine cutting out and the poor preformance is probably because of of the bike only running at half capacity, but who knows.... 

[DoD#i]

Yes, it likely is running on one cylinder, from what you've said before.

Mostly the terminology is just helpful to have us on the same page when we are not able to look at the bike all together, less confusion about what's happening.

For the moment, your most likely temporary solution to the starter button not cranking the bike will be to bypass the clutch switch. Open the headlight, find the two yellow-green wires in one small black jacket, unplug them and plug together the two things that were plugged into them - see if that lets you use the starter button as usual. If so, you can replace the clutch switch later. If not, post back and we'll follow the less likely problems.

My guess is that you have an electrical/spark issue with the non-running cylinder, given some apparent response to taking the wires on and off. Other possibility is lack of fuel, or way too much fuel (less likely). Take the spark plugs out and have a look at them. Try swapping the spark plugs and see if the problem follows the spark plug. If it does not (the same cylinder still does not fire), swap them back and (more work) swap the coils left to right.  If the problem follows the coil, the coil (or the wire to/from it) is the problem. If the problem stays on the same side, start looking at fuel delivery issues (carb problem or vacuum leak) on that side.

[BaltimoreGS]

Before you start tearing the bike down, run a compression test and make sure you don't have a valve stuck open.

-Jessie

[JChivell]

Yeah, compression test is absolutely going to be my next goal. I just need to buy a compression tester.

By the way, whats the best way to use a compression tester. I used to have one....but I dont think i was using it right....


So. I had a small vacuum leak on my right carb, but I fixed it.

The bike still does work right. It works "better" though. Both plugs are firing (I switched the cables and everything like you said, but same results), but the right cylinder doesnt get hot at all when its warming up. The starter button works fine now. It started working after I shorted it the first time.

Is it a bad idea to use the bike to and from class with one cylinder not working correctly? It runs.... but it just under preforms. Thanks for all your help.

[BaltimoreGS]

Someone correct me if I'm wrong but I believe the GS has 12mm spark plug threads.  A proper compression test is done with the bike at operating temperature.  Remove both plugs, install the gauge, hold the throttle wide open and crank the engine over a few times.  Around 150 psi is normal but more important should be that the cylinders are within 10% of each other.  If compression is low, pour a little oil in the cylinder and see if the reading rises, that is an indication of worn rings.  I had a burnt valve on my '01, it had no compression in the right hand cylinder.  Good luck!

-Jessie

[Paulcet]

Is it a bad idea to use the bike to and from class with one cylinder not working correctly? It runs.... but it just under preforms. Thanks for all your help.

Does it run on both cylinders when RPM is over, say 3,000 and throttle over 1/4?  If so, you can use it.... I did for a couple of months until I figured out that I had a clogged pilot jet.

[JChivell]

I think it does right around 3000RPM. Sometimes it will idle there for a minute, but then drops down to 1200-1400 and sounds rough.

How would I really know if the other cylinder is running?

And I took apart my carbs, but didnt really know what I was looking at and put them back together. They looked pretty clean, but who knows.

Will test compression today...hopefully...

[JChivell]

Ok, compression test was fine. There was about a 10psi difference, the cylinder that is not firing being a little higher.

So From what I can tell......  Good compression, good spark, but it needs fuel.

So clean the carbs? Would that be my next step?

[Paulcet]

My own trouble (and solution) with one cylinder not firing at low RPM: http://gstwins.com/gsboard/index.php?topic=43834.0

[mister]

Ok.... So, I just bought a 92 GS500

PICS. Pics or it didn't happen 

Michael

[JChivell]

Yeah.... To be honest, I'm gonna try and fix the bike before a waste time taking pics.

I'll get some up soon, if I can figure out how to do it.

Btw, can anyone tell me what to do with my carbs? The problem has been isolated to fuel, but im not really sure what to do. I read on that other post about checking the fuel height in the bowls? I have no idea what Im doing, or where to go from here. Any thoughts or comments? Ive taken them apart before, but honestly have no idea what Im looking at/for. Thanks again for all your help.

Oh, And i have been running seafoam in my tank. I took my bike out yesterday and rode on the highway, roughly 60-75 MPH for about an hour. After that, the bike seemed to run SO much better. It even idled with both cylinders for a while at 1300rpm. AND there was a little oil on my engine where the spark plugs are, it seemed to be collecting/leaking there? That sounds like a problem to me, but it out of my realm of experience, any thoughts or comments would be greatly appreciated. Thanks!

[BaltimoreGS]

If you are running on one cylinder at low RPM's it is probably a clogged pilot jet.  If you have a pre '04 bike it has 2 jets in each carb, a large main jet and a small primary jet.  Those have to be unobstructed for the carbs to work properly.  Check online parts microfiche to get a location reference.  While your bike is idling, pull off one spark plug boot and see if the engine dies.  If so, the cylinder with the boot still on is not working.  Good luck!

-Jessie

[Paulcet]

Have you found the wiki yet?  Good info there.

Checking float height: http://www.bbburma.net/FloatHeight.htm

As for cleaning the carbs, "nothin' to it but to do it".  Do one at a time, and be careful.  You will need to make sure all o-rings are in good condition and that all orifices are clear.  Particularly the little brass jets and small air passages.

[JChivell]

Awesome, that gives me some avenues to explore. Thanks a lot, I'll see what I can do.

Will post pics when bike runs. Dont worry...

Thanks.