idling/stalling issue...

[nabrams]

The first time I did a valve adjustment it looked intimidating, but it really is not. It is, however, very time consuming, if you've got the shim-and-bucket system. And, if you don't have the right size shims it's a pain hunting them down (dealer, eBay, or wherever).

First of all, do a compression test (record the numbers) so that you can compare to the numbers you'll get after valve adjustment.
Second, get a proper set of feelers that go down to 0.0015 inch, and verify current clearances (measured when the cam is facing away from the shim). If you can't even get the samllest (0.0015 inch) in, then you know you've got effectively zero clearance - BAD (and very common on our old, uncared for bikes).
Third, get a proper manual (Clymer is usually decent) that will walk you through the adjustment process. Also, see the many posts on this site that have lengthy descriptions on how to do it - use the search feature.
Fourth, re-check compression and compare to values recorded prior to valve adjustment - you may have hugely improved numbers. If compression is still low then you've got bad rings or burnt valves, etc.

Let us know how it turns out.

[Fare]

I wish I would have known it was more than a "adjustment" and would have worked on it earlier (this is probably another week I'll have to wait to ride -_-)

Before I was yanked away from my work and forced to spend time with the miss, I attempted to do a check. The cam (I'm guessing this is what its called, looks like a circle that grew a tumor) is perpendicular to the shim and I cannot get anything between it (bought a "master feeler" set, which had a .0015 inch as the smallest feeler (if I remember correctly)) I'll look into this compression test (hopefully I can do it with a broken gasket till my new one comes in).

Thanks,

Fare

[Fare]

So this is probably no good, but I can't get a .0015 in. feeler in most of them (5/8 ) (unless i'm doing it wrong...)

Do i have to buy that special tool to replace the shim or is there a way to do it without... i say that because it looks like i'd have to buy the tool, wait for it to ship, then take out the shims, play around with them, then probably order more... guess i should just assume i'm not going to ride this year...

[nabrams]

You've gone this far, and the cost of the tool is not going to break the bank. On some bikes, it can take weeks of riding/tinkering to work out all the kinks. You need to accept that if you expect to restore abused bikes with 45K miles on them.
What about compression numbers?

[Fare]

I suppose I can do that while I wait for the tool (ordered it today). I need to put everything back on (carbs, airbox, tank). I am waiting for replacement gaskets to come in, would a damaged gasket (valve/cam gasket) make a difference, other than oil leaking (don't know this for sure, just guessing that it would happen).

If I was a religious man, I'd say "god bless you Nabrams." Your posts resurrecting my threads from the 2nd or third page give me hope.

oh, btw, I'm not worried about the price of the tool. I would say that I'm impatient, but between z1enterprises, bikerbandit, my local dealerships (which I feel very uncomfortable being at...), fleabay, local auto places and (as little as possible) wally-world, I'm getting sick of buying things and waiting for them to come in. all part of the fun right? I'm sure that I'll be a master GS850 mechanic by the end of this...

[nabrams]

You don't have to put ANY of that stuff back on in order to do a compression test (valve cover can stay off too - oil will be flung about, but the compression test is for the pressure in the cylinder). Just make sure you read the instructions that come with the compression tester.

I'm glad I've been helpful, but the truth is you don't need me - everything I've been telling you has been posted here a million times. If you spend some time using the search feature and doing some reading, you'll save yourself a lot of aggravation, time, effort and money.

[Fare]

To be completely honest, I spend a great deal of my time, at work, at home, and whatever (don't let my boss see this!) reading the forums, inside and out. I either lack confidence in what I read pertains to me or I just want confirmation that I'm doing what I'm supposed to (never touched a ratchet set before my bike, so I'm not exactly mechanically inclined). I apologize if I've been annoying or whatever, suppose I'll take that bullet for the next person who is in my shoes...

I'll do that compression test as soon as I get the opportunity to then. I was under the impression that I should do the compression test when the engine is warm...

[nabrams]

I wasn't biting your head off. It's just this - If you wait for me (or someone else) to answer every question you have, then it will take even longer for you to get on the road. You've got to dive in. It's true that a warm compression test more accurately reflects real-time running conditions, but a cold compression test can tell you a lot - see other posts. By the way, I've learned EVERYTHING I know about bikes myself - you can too.

Good luck, and let us know. Now, I'VE got to get back to work

[Fare]

ok, more not so good news....

cam cover not screwed, bad valve gasket, no airbox, no carbs, no tank

numbered left to right, as sitting on the bike...

1 dry = 90 wet = 240 (stopped as oil gushed from all orfices)

2 dry = 0ish wet = 40

3 dry 30 wet 70

4 dry 110 wet 170

[nabrams]

Obviously 2 & 3 are worrisome right now (they probably also have the worst valve clearances). Proceed with the valve adjustment and measure compression again. In many cases that will bring compression back up to acceptable levels. Let us know.

[Fare]

Kinda a question, more of an observation.

I spent the weekend using the tool to do the necessary valve adjustments. as mentioned earlier, they are way off. Using a 2.30 shim that I bought at a local dealer (for a heavily scalped price...) and some math, I was able to deduct what shims I need. My questions are:

1) do the large gaps make us believe that the bike didn't have a valve check ever or just recently.

2) do you think that the large gaps are the reason for the low compression.

At this point it all theory-craft until the valves come in later this week, I was just wondering and perhaps you all can help me wonder more correctly.

here was my results...
___________________________CYLINDER____________
__________________||__1__||__2__||__3__||__4__||
Present Exhaust Shim_|| 2.75 || 2.55 || 2.65 || 2.65 ||
Needed Exhaust Shim_|| 2.70 || 2.35 || 2.50 || 2.65 ||

Present Intake Shim__|| 2.60 || 2.60 || 2.60 || 2.55 ||
Needed Intake Shim__|| 2.50 || 2.40 || 2.40 || 2.55 ||

Dry Compression_____|| 90 || 0 || 30 || 110 ||
Wet Compression____|| 240 || 40 || 70 || 170 ||

I know not much can deducted till the shims come in and I can know for sure, but it just seems like the compression results were good on the shims that were dead on or close to what they needed to be and the ones that are 20 or 15 off, they were very poor (which hopefully means my engine is still good and wont have to be taken apart and whatnot).

Thank you to Steve for his excel spreadsheet,

Fare

P.S. are the cylinders properly labeled? 1 being the leftmost if you were on the bike, 4 being the rightmost.

[Uncle Jetski]

I had a similar problem

On my 1982 450T, it would go for 200 yards, then stall. I could start it up right away however, and that's the key. If it takes 15-20 minutes to re-start, it's probably the coil. If it takes 5 minutes, the bowl might not be filling. In my case, it re-started in 10 seconds. Check for a short/loose wire, or replace the igniter.

[Fare]

Ok, getting closer.

Everything is installed, valves up to spec, a quick compression test (cold) vields significant increase. (125 where it was 0)

Plop the tank on (i wanna hear it start) and it doesn't start. checked #4 spark plug, theres a blue spark (no clue if its a strong or weak, nothing to compare it to) so i'm getting a spark somewhere. My guess, however, is an air leak somewhere. after i crank longer than i should, i sometimes hear a soft hiss.

going to do some more searching while i wait for the battery to charge, since it reads ~11.40 now (hasn't been charged via bike or charger in a few weeks, plus the excess cranking and it accidently getting wet (damn faulty tent thingy)). Anything quick i should check? losen carb screws, look for particular leaks somewhere?

Thank you,

Fare

[Fare]

guess i'll treat this thread as a journal, and just document my road to gray hair....

testing the coils, with the caps on, 1-4 is 20kohms, 2-3 is is the same. the caps are brand new. looks like i'm investing in coils now...

[slugsride]

Your cylinder numbering is correct.

Did you turn it on prime for about 30 seconds?

Maybe one of the veterans can correct me on this, but I think when trying to start with low voltage you still get spark but the advance control is messed up (if yours is electronic advance).