troubleshooting a troubled bike

[maddietheblond]

Hello everyone!

  My name is Maddie, nice to finally have the initiative to become part of this forum. I have done a lot of reading, but never had the reason to post or the knowledge to really help out. So, here are the details.

1994 gs500E

I put about 4 tanks through before it finally died out. I laid it down once.
New parts since it acts funny: petcock, oil, spark plugs, gas lines, fuel filter, gas, battery.

Symptoms: about a tank ago it started having the sticky idle bit where I had to blip the throttle to get it to go back down to idle. Then after a bit of time it would die at idle. then after a while it just wouldn't start at all.

I have cleaned the carbs, checked the float height (small adjustment), including as well thorough cleaning of the pilot jets and every other tube and hole i could find. I am really trying to get this bike up and going on my own, so going a bit further into possible problems?

The bike will occasionally turn over for just a few rounds, but then die out. some white smoke coming from the tailpipe. I can thoroughly say that the carp is clean, that fuel is getting to the cylinder (wet plugs) and spark (touching it to the outside of the engine and verifying spark. what the heck am I missing as to why its not turning over easy anymore? I could check the valve's, I have shim stock and a shim set for testing. I am really curious what I am missing!

~maddie

[DrtRydr23]

How many miles on your bike?  Most likely you're due for a valve adjustment anyway, which may also help your problem.

Also, is the new fuel filter an inline filter or did you replace the tank petcock?  If it is an inline filter that can cause fuel flow problems.  Most people here will tell you to scrap an inline filter and do a valve adjustment and carb sync.

[JAS6377]

Yep. Valve adjustment all the way. I can vouch for that as of tonight lol. Also, hanging idle generally means a lean condition. I would also venture to say that the inline filter is causing a bit of fuel starvation. Do you have any upgrades or anything that we should know about (exhaust/air filter), or is it completely stock?

[maddietheblond]

Completely stock bike with 10K miles. I pulled the filter off, so just solid lines. I replaced the bike side petcock, not the tank side. I am going to do a valve adjustment tomorrow. Any other suggestions?

[JAS6377]

Well, if the filter is off, that will definitely make it run lean. Plop that filter back in there. Or, grab a K&N and rejet.

Before you do that, though, you need to get it to actually fire up lol. So, I'd stick with a valve check and carb sync, then move on from there. We'll be here to help.

Oh, and welcome to the forum. I forgot to say that before lol.

[maddietheblond]

Thank you for the welcome! carb sync? as in making sure both the floats are at the same height?

Also, for the valve adjustment. the guides I found claimed that if it was off I should replace the shim with the correct size. Do you happen know what type of shims they are? I have some bolt shims, and some shim stock. just trying to figure out what I need before I get in there. Also, do you think I will need a new gasket? or if mine is in good enough condition it is re-usable?

[RossLH]

Well, if the filter is off, that will definitely make it run lean. Plop that filter back in there.

Nope. Fuel filters restrict the flow of fuel, as it is only gravity fed rather than mechanically pumped. Having a fuel filter can and will make the bike run lean. Keep the fuel filter off, it is entirely unnecessary.

[fetor56]

If your intending to keep the bike for awhile Maddie it's a good idea  to buy yourself a Service & Repair Manual.

[adidasguy]

Completely stock bike with 10K miles. I pulled the filter off, so just solid lines. I replaced the bike side petcock, not the tank side. I am going to do a valve adjustment tomorrow. Any other suggestions?

One thing comes to mind: is gas flowing? Is there gas in the tank? Pull the line that goes from the frame petcock to the carbs. Put the petcock in PRIME and then see if gas comes out. If nothing comes out, you solved your problem.

[radodrill]

Well, if the filter is off, that will definitely make it run lean. Plop that filter back in there.

Nope. Fuel filters restrict the flow of fuel, as it is only gravity fed rather than mechanically pumped. Having a fuel filter can and will make the bike run lean. Keep the fuel filter off, it is entirely unnecessary.

He was referring to the air filter 

[The Buddha]

Thank you for the welcome! carb sync? as in making sure both the floats are at the same height?

Also, for the valve adjustment. the guides I found claimed that if it was off I should replace the shim with the correct size. Do you happen know what type of shims they are? I have some bolt shims, and some shim stock. just trying to figure out what I need before I get in there. Also, do you think I will need a new gasket? or if mine is in good enough condition it is re-usable?

Were the out of spec valves tight or loose ? If you had 3 loose but 1 tight, that tight valve will keep it form running on that cyl. Since we only have 2 cyl, it means it will start but die in 5 sec.
And is your choke working ?
Cool.
Buddha.

[DrtRydr23]

If your intending to keep the bike for awhile Maddie it's a good idea  to buy yourself a Service & Repair Manual.

+1.  Clymer has worked fine for me.

Also, a carb sync involves equalizing the vacuum between both carbs so that they work in conjunction.  There is a tool you have to buy/make that measures the vacuum, and a screw between the carbs that you turn to equalize them.  Also, you need to get the correct size shims from a dealer or the internet, shim removal tool (bucket compressor), feeler gauges of appropriate thickness, and a little telescoping magnet helps as well.  A manual will help you immensely with this stuff.

You won't know what size shims you need until you get in there and check the clearances.  You can reuse the cam cover gasket, at least I did, unless it starts leaking in which case obviously replace it.

[maddietheblond]

Thank you Everyone!! So I do have the Clymer manual, and it has been immensely in everything except for actual troubleshooting. I slept hard and am currently at work (yes, I work on sundays too. Bain of being maintenance for a building with problems) but have grabbed our feeler gauge set.

This morning I made sure the air filter was in and took the fuel filter off, same problem still persists. Since I replaced the petcock I know that it runs on prime, and did a double check and it flows quite well. And yes, the choke does work as I just replaced the cable for it was seized when I bought the bike and thus never present. So any time I ran it was sans choke. And it always fired right up, until it started having those issues (could that have been from starting it without choke?). I am doing 2 things here, trying to figure out the problem and make sure that it does not re-occur. Thank you everyone! I will post results of the feeler tests tonight.

~Madeline

[The Buddha]

You cant cause problems starting it without choke.
Look @ the valves. I think its one ot more tight valve.
Cool.
Buddha.

[maddietheblond]

Alrighty, sorry for the delay on the reply. Pulled the valve cover and took my shim set and set to work. My shim set goes as low as .0015, and here are the valves starting at the bottom right and going clockwise.

Bottom right: .0015 does not fit
Bottom left: .0015 fits, .02 does not
Top left (rotated camshaft for this): .0015 fits, nothing else does
Top right (prior to rotation): .04 fits

So, should I pull the shims and measure them? or just go ahead and order the .05 less as recomended? maybe .05 and .1 below and return the ones that I dont use?

Thanks!
~M

[The Buddha]

Bottom right I am guessing is right intake -  OK see if you can spin the bucket. If it will spin free, your valves are not hanging open to cause your problem. Atleast not if it is over .0010".

The valve should be set so that .0015 (the thinnest we can find on this planet)  fits even in the tightest one, just as a caution and so you dont have to tear into it in a few 100 miles.

Let me read your original post and see what hits me. You may still have a tight one there, so it can happen to be the cause. But let me see if it could be somehting else ... I may have got smarter in the last 2 days ... not happened in the last 44 yrs but hey we all hope.

Cool.
Buddha.

[The Buddha]

I missing as to why its not turning over easy anymore? I could check the valve's, I have shim stock and a shim set for testing. I am really curious what I am missing!

~maddie

Turning over easy ? You have a decent battery in the thing ? If you dont get it spinning up atleast 300 rpm, it will probably not suck enough fuel to fire and light it.

[maddietheblond]

Spin the bucket, as it spin the crank? I did a full rotation and nothing seems to be hanging at all. Whats the next step buddha?

I have a new battery in it, and I keep it attached to a trickle charger for a hour or two before each mechanical intervention. sometimes I have to jump it with a lawnmower battery. it gets full rotation, of that I am sure.

[The Buddha]

Spin the bucket, as it spin the crank? I did a full rotation and nothing seems to be hanging at all. Whats the next step buddha?

I have a new battery in it, and I keep it attached to a trickle charger for a hour or two before each mechanical intervention. sometimes I have to jump it with a lawnmower battery. it gets full rotation, of that I am sure.

Spin the valve bucket - with your fingers. If the cam isn't bearing on it, it will spin loose and free, if its got the cam it will drag and make it hard.
OK If the battery is good - does the motor spin up fast when trying to start ?
Cool.
Buddha.

[maddietheblond]

it spins the same as it has from day one. sounds like a proper bike starter.