'79 GS850 problem(s)

[Stevin]

Good Morning GS'rs

Let me start by saying I am very happy I found this place, I recently purchased a 1979 GS850, I will try to be as detailed as I can about what we have done, and what problems I am facing. I also should say that I am a genuine "noobie" when it comes to alot of lingo regarding bikes.

I bought this bike about 3 weeks ago, and the previous owner said it has set untouched for about a year and a half, I brought it home, emptied the bowls, and gas tank, and replaced it with new gasoline.

I bought a new battery from Autozone, put it on, and BAM! the bike started on the 3rd try, needless to say I was happy. But it ran sluggish, so about a week ago I found these forums, and learned about varnish, and the effects it has, so I got my friend and we removed the carbs, and cleaned them (including jets, etc) put it back together, ran better, next day we did it again, ran a little better, 3rd day, did it again, ran a little more better.

But still, it just didn't seem to have the power, or accelleration that it should have, so further investigation led us to discover that the exhaust pipes were not heating up "properly"... 1 and 4 remained very cool, while 2 and 3 got hot, very quickly.

I called a shop, they said it could be a couple differnt things, he said that there are 2 coils on this bike, 1 coil runs pistons 1 and 4, the other coil runs 2 and 3, he said its possible that one of the coils are bad.

He also said it could be an electrical problem, and plugs 1 and 4 may not be firing at all, thus I could be running on 2 cylinders, which would explain the low power.

Or it could be air/fuel mixture coming from the carbs, but he warned me about adjusting these myself, cause I could potentially "lean" it out to much and burn a whole in the pistons.

I am hoping to find out if there is anything else I can do myself to try and fix this problem, I really dont want to sink a ton of money into the bike.

Since I found so much helpful information here, I thought I would post my specific problem and see what you all thought, again I thank you for your time, and look forward to your comments and suggestions.

Steve (a new GS'r :-D )

edit: Bike has 28k miles.

oh and here is a picture of the bike:

[nabrams]

I've got pics of my boys on my bikes. I should post them sometime.

I've restored four non-running bikes over the years. Searching this forum has been my primary source of information - most times I didn't have to ask questions - they've been asked a million times before. Learn how to use the search feature.
Bike problems (especially electrical) require a careful "process-of-elimination", methodical approach. You DO have a Clymer or shop manual, right? This is an absolute must.

Regarding your 1 & 4 cylinders not firing:
You should visually verify spark on 1 & 4 - if you don't know what I mean by "visual verification of spark" then find out by searching this forum or reading your manual.
Something I've learned after restoring four non-running bikes: I originally thought that electrical components (igniter, coils, R/R, etc.) either work 100% or don't work at all. Now I know that is not true. All of the electrics can fail gradually and show up as intermittent problems until they finally fail totally.
I've had R/R (on two Suzukis), coil and electrical rotor (on a 1980 Honda CB750) that failed gradually. I spent tons of time messing with carbs when the problem was electrics all along (which I found out when the component finally died totally).

Invest the time to learn your bike and you'll save a TON of money.

Here's some advice I gave someone:

Unless you KNOW that the shop is good don't even think about bringing it to them.
You're going to have to meticulously clean the carbs and verify that everything is working properly (no torn diaphragms, leaking floats, plugged jets, etc.). You'll need to invest between 30 to 60 hours of time (if you've never worked on bikes) to go through your bike and verify all the typical problem areas (air/exhaust leaks, carb issues, charging issues, valve clearance, and so on...) - see my other posts about restoring bikes that have been sitting for a while. You'll need to buy some tools. You'll need a good manual (Clymer is decent, shop manual better).
After all that you'll know your bike's condition fairly well. You'll most likely have issues pop up every season, so it pays to know your bike. You'll also save a ton of money and do a better job than the shop does.
For me, the whole point of these 80s era bikes is to be able to work on them and not have to pay exorbitant fees to shops. I started with very little knowledge and with the help of this great forum I've restored four non-running bikes over the past 5 years (Two GS450s, a Honda XL350 and a Honda CB750).
If you've got lots of cash, just buy a new bike and be done with it.

Good Luck, and keep us posted on your progress.

[chuckycheese]

Cool!

That's a good lookin' cowboy!!:-D :-D

[GS550joe]

check the repair pages

check the repair pages talked about in this forum.... print them out and make you a book to reference when problems occur.. take note of what most of the members agree about ... if 250 membrs have tried and it works.. beleive them... they won't be leading you astray.....

as for the cool pipes.. take the plugs out and check the gap and color.. if dark and grungy... replace all 4.... also check the timing setings... then check for any ther color then brass on the power wires going to the coils..clean 'em to shiney and retry... also make sure the battery ground is solid and not loose ...

spray arund the intake boots btwn the carbs and head while running if the speed picks up... u need to replace the o rings on the head side of the boots/ or the boots themselves..

These will get you started on the ez stuff.. there are more detailed instructions that others could be giving..

Joe

[mark]

Welcome to the '79 850 club.

When you cleaned the carbs, did you pull them apart completely and soak them in carb cleaner, blow the passsages, etc. Don't just take parts off and spray with a can of carb cleaner....not good enough. Did you set the floats, put in new o-rings etc? Are the carbs synchronized? All this is important on your machine. Really, its not that hard to do....make sure you do it right. There's a good article on the home page on carb cleaning.

You're 1 and 4 problem could be a coil. That's easy to test...just swap them and see if the problem moves to 2 and 3.

You also have points ignition, unless someone modified it. Are you're points set correctly? Are they pitted? Is there too much arcing between them when the bike is running. Is your timing right? The points for 1 and 4 are on the left side as you look at them with the cover off. I eventually bought a no-points ignition for mine, but that's another story.......

Test voltage from the battery to the orange wire that runs from your coils. If there is much more than a drop of 1 volt or so, do some cleaning of your connections.

Pull your plugs and look at them. If you have fouled plugs, replace them. I have had plugs foul and not fire after that no matter how much I cleaned them and how good the ignition was. Some say soak them in vinegar overnight, that I have not tried. But keep some extra plugs around while you are working this out.

I agree with the above post on the shop advice. Unless its machine work, you don't need to take it to the shop. Everything you need to do, with a few tools and a little help you can do yourself. In fact I would check your air screws, and adjusting them is a part of carb synchronization which you should do anyway. Just note how many turns it takes to turn them in and turn them out the same amount after checking them.

I would do a compression test on your motor, just to let you know the general condition of the motor.

Make sure your airbox is sealed PERFECTLY. More than anyone thing the airbox needs to be right. You won't be able to tell if your bike is running well with the airbox off. Put it on before you judge what you have done.

You have the potential to have a GREAT bike. Take the time to learn how to do the maintenance and TLC that it needs and you'll have a great time with it.

P.S. I'm jealous of your stock exhaust!

[Stevin]

Update:

Thanks for all the advice, the coils tested fine, voltage from the battery was perfect.

The points were pitted however, so I pulled them off, sanded them down perfectly flat, also while in the the timing was off, so I adjusted that (and learned by mistake that "T" did not stand for "timing" but "Top Dead Center" my haynes manual failed to mention that, so after timing it on the 1-4 and 2-3 hash marks it ran worse, but all good once we figured out that "T" meant top...) also installed 2 new condensers from bikebandit.com

I pulled the plugs, they were less than a week old, but were indeed dirty, as if the machine was running very rich, but I concluded that was because was ran with the choke on full ALL the time, I am putting new plugs in again this evening.

but long story short, the bike runs like a new machine, it seems the points and timing were the problem, all 4 cylinders fire, still needs a little fine tuning, the exhaust from cylinder 4, heats up much slower than 1, 2 and 3.

thanks for the advice, you all saved me a ton of headaches, and I am greatly enjoying learning this stuff, (2 months ago I didnt even know what a carb was or what it did, NOW I can dismantle one, and put it back together)

[tfb]

Victory is sweet.