GS1OOO misfire and blue smoke

[ozzydog]

Hello everyone, I am new to this site and have used the seach function but could not find anything that sounded similar to the problems I'm having, so I would like to ask for your help please.
I have a 1979 GS1000E, it is a US import and is showing 32,000 miles. It is standard apart from electronic ignition that looks like it was fitted some years ago and a neta 4 into 1 exhaust which I fitted about a week ago as the old 4 into 1 was blowing, but this has not changed the symptoms the bike is having.
I have no history for the bike, I got it from a friend who bought it off of ebay and I'm having problems with cylinder no 1 not firing very often. I checked and changed the plugs and cylinders 2&3 look fine but cylinder 1 is covered in oil and cylinder 4 is rather sooty. I have a spark on all 4 cylinders.
The bike coughs and misses when you try to start it but once running it seems to idle fine even though its only running on 3 cylinders. There is blue smoke on start up and when its running. When out on the road it misses right though the rev range not at a specific rpm and its not all the time as it does clear now and then.
The friend I bought it from reckons he removed and stripped the carbs to clean them and last week a mechanic friend of mine checked the coils, ht leads and plug caps and all seemed ok, but he thought it had a broken piston ring.
I would just like to make sure its not something simple before getting worried. Do you think pehaps the carbs were not cleaned well enough or it could still be a coil problem? I did notice when I changed the exhaust that on cylinder 1 where you can see the exhaust valve it was all full of oil and I wanted to ask if this is just due to it not running correctly or a sign of something else?
I would be very grateful for your advise as my mechanic skills are not very good but I would like to try and get this bike running well before maybe restoring it to its former glory.
Thanks very much for your time reading this and for your help
Best regards
Geoff

 

[Nessism]

Blue smoke is oil, so you need to pull down the top end on the engine. Measure the cylinders and pistons for wear and replace parts as appropriate. Also, pull the valves out and replace the valve stem seals at minimum - check for valve and guide wear also. Once you get all that squared away I'd then attack the running problems. Having fresh clean carbs, along with appropriate jetting for that header exhaust is critical. Not sure where your bike is at with regard to these things so I suggest starting with the basics since the bike had no known history.

 

[Big T]

1st, I recommend going to the BassCliff site

http://members.dslextreme.com/users/bikecliff/

And reading your way thru everything. It will save you lots of time and trouble in regards to lots of niggling problems you'll have with the bike.

Blue smoke does mean oil. It sounds like your #1 is pumping a fair amount of it.

Before you start tearing the head off, what are your compression numbers across all 4 cylinders?

Your oil pumping could be as simple as a bad valve stem seal gasket, or stuck rings in the #1

To address you other questions, the carbs may not be fully clean. They need to be stripped completely, cleaned and reassembled with new O rings.

Coil problems are less likely. Swap the #1 HT lead with #4 and see what happens

Stuck rings are common in bikes that have sat for a long time and stuck rings in #1 generally mean the bike sat on the sidestand.

If that's not it, get out the wrenchs and have at the motor. There's a factory service manual on BassCliff's site

 

[tkent02]

Stuck rings are common in bikes that have sat for a long time and stuck rings in #1 generally mean the bike sat on the sidestand.

And sometimes they can be unstuck by riding. If you can get it running well enough and if the rest of the bike is safe enough take it out and see if things get better. A new plug may help it run better for a while, wind it out and see what happens.

First thing to do is the compression check as Big T says.

 

[hampshirehog]

Hi Geoff - welcome to the nuthouse.

The smoke could be worn bores / rings, stuck rings, broken rings or worn / hardened valve stem oil seals. I would run the bike first and put on a few miles to see if it is stuck rings - if you're lucky and it is it'll save a teardown. If it doesn't cure itself the guys on here will talk you though what to do. Also, try dropping some ATF in the plug holes and leaving the bike to sit overnight. Turn it over on the starter the next day with the plugs out to get rid of the oil and pop the plugs back in. The ATF may help free off stuck rings.

The misfiring could be down to the carbs, the ignition, plug oil fouling or valve clearances.

Checking the valve clearances is a must do job - if they're too tight you'll quickly build up a bill for new valves / valve seats as they burn out. Good tutorial on Cliff's website http://members.dslextreme.com/users/bikecliff/images/gs850valve_adjust.pdf.

I like the cable tie method for changing shims - have a look at: http://members.dslextreme.com/users/bikecliff/images/valve_tool_zip_tie.pdf If you need shims give me a shout - I may be able to help you out.

Plus carb cleaning - there's only one way to do it - properly. Too many times people skimp on this and it ends in tears. Strip the carbs completely (follow the tutorial on here to the letter and make sure everything is 100% clean - http://www.thegsresources.com/files/vm_carb_rebuild.pdf). For worn O rings get some new ones from Robert Barr - you won't beat his price or his service: http://www.cycleorings.com/

Cheers - Wally

 

[ozzydog]

Hello, I just wanted to say a big thanks to you all for your help and advise and for the really useful links. I thought I'd give you an update, the misfire is now gone and the bike is running much better. I got a secondhand coil off a mate and fitted it & hey presto no misfire which was a surprise. Didn't get a chance to ride far as had to leave for work but its much better than before, also not smoking much now, just a little when you start it up although it dosen't look that blue now.
I tried doing a compression check but my tester is ancient and of the push in type so I could only get it in cylinder 1 & 4 because of the shape of it. It gave me 90psi on 1 and just under 90psi on 4. I don't trust this as its 40 years old and rubber so am gonna pop round a friends on sunday and use a screw in type that will fit all 4 and hopefully it'll give a true picture and help to work out the next step. Also I just put some ATF in the plug holes this afternoon and gonna let it sit overnight just incase the rings are sticking, many thanks for this tip
Thats about as far as I've got for now, I'm going to a rally at the weekend so I think I will chance taking the bike along and see how we get on.
Thanks again to you all for your help, no doubt I'll be back if I have to pull the top end as even with all the info on basscliffs site I'm still bound to get in a muddle but feeling more optimistic now.
Cheers
Geoff

 

[Big T]

Geoff,

Go ride that bike and see if it wakes up a bit more as the miles go on.

If so, then start on the basics

And watch the oil level to see how much oil it's using

 

[SqDancerLynn1]

Don't forget to open the throdle when you check the compression

 

[sscott]

Ok, I gotta ask sice I read this thread and worried after reading the post about sitting on the side stand. It sounded like if a bike is sitting on its sidestand for a long period of time it can cause problems with the rings in the #1 cylinder. How long does it have to sit for that to happen? Mine has been sitting on the side stand since January when I rode last.

Should I ride it a bit then put it back on center stand or just put it on the center stand and not worry about it?

 

[tkent02]

The center stand is always better, for the tires, the engine, and for the carbs but you really won't get problems from a month or three, unless you are in a humid environment.

 

[Big T]

Ok, I gotta ask sice I read this thread and worried after reading the post about sitting on the side stand. It sounded like if a bike is sitting on its sidestand for a long period of time it can cause problems with the rings in the #1 cylinder. How long does it have to sit for that to happen? Mine has been sitting on the side stand since January when I rode last.

Should I ride it a bit then put it back on center stand or just put it on the center stand and not worry about it?

A couple of months won't hurt anything unless the #1 float needle is weak. Then, it will just flood #1 cylinder, causing rough start up

What I'm referring to is a bike that got "parked" for 2-10 years, on the sidestand with gas in the carbs. Since the 4 carbs are linked, the fuel pressure can cause gas to flow into #1,(being the lowest cylinder) and wash off the oil. Result - stuck rings and bad compression on #1

Go ride your bike and don't worry about it. Centerstand never hurts, as Tkent says

 

[ozzydog]

Hello everybody, well I'm really sorry to be back so soon but things have got a bit worse.
Took the bike out for a run and did about 30 miles and it ran ok a bit rough below 3000 rpm but fine above this. It smoked a little bit when it started from cold but once warmed up no smoke at all. Later on I removed the plugs and put a bit of ATF down each plug hole and left it over night. Today I turned it over a bit and then put the plugs back in and it fired up but was running really rough and the pipe on cyl 3 was cold. It did then chime in and run on all 4 cyl for about 5 mins but was running bad and wouldn't idle and then died and now I can't restart it. I managed to flatten the battery trying to get it going so thats now on charge. I checked I have a spark on all 4 cylinders and that I have enough fuel in the tank and the fuel tap is on and fuel appears to be getting through as the plugs are wet. I just wondered please if anyone has any idea of what I may of done to it as it seems wierd that it was running ok yesterday. Does this sound like its probably be a carb problem?
Many thanks for any advice that you may have
regards
Geoff

 

[hampshirehog]

Geoff, as the smoke disappeared when the motor warned up it really points to the valve stem oil seals getting tired - they go hard with age and only make a decent seal once they have warmed up and become a bit softer. You can run the bike like this and you won't do any real harm (though the top end will obviously carbon up more quickly and you'll use oil). It's an easy job to cure and the parts will only cost you around ?60 all in.

The bike running like it did and now not starting looks, as you suspect, like the carbs. Rather than fannying around the only definite cure is to remove and clean - really, really clean - and set up as per the manual. You'll almost certainly need the O rings for the rebuild but they are peanuts.

Plus check those valve clearances.

 

[Nessism]

Maybe you fouled the plugs by dumping that ATF in the cylinders?

 

[ozzydog]

Maybe you fouled the plugs by dumping that ATF in the cylinders?

hopefully thats whats happened, I did take out the plugs to check for a spark and they looked clean but then I put the 1st set of plugs that I cleaned up back in but by then I'd flatten the battery so will try again tomorrow when its charged, fingers crossed she fires up........

Many thanks
Geoff

 

[ozzydog]

Geoff, as the smoke disappeared when the motor warned up it really points to the valve stem oil seals getting tired - they go hard with age and only make a decent seal once they have warmed up and become a bit softer. You can run the bike like this and you won't do any real harm (though the top end will obviously carbon up more quickly and you'll use oil). It's an easy job to cure and the parts will only cost you around ?60 all in.

The bike running like it did and now not starting looks, as you suspect, like the carbs. Rather than fannying around the only definite cure is to remove and clean - really, really clean - and set up as per the manual. You'll almost certainly need the O rings for the rebuild but they are peanuts.

Plus check those valve clearances.

Hi there, well I'm gonna bite the bullet and order an O ring set and follow the guide in the link to clean them good and proper. Even if it doesn't end up solving the running problems I guess they are 30 years old now and a long way past their best and it can only make things better. I will be glad if its only the valve stem oil seals and shims that need doing, I had been worrying it would need a rebore etc as I have no idea how genuine the mileage is, for all I know it might be 32,000 round the clock. I was just gonna use it for the run this weekend and then get stuck into it but I guess it never pays to make plans
Thanks again for the advise
Cheers
Geoff