Ok, so I've completed my valve adjustment. The left intake valve I had to go down two shims from 260 to 250. After that the clearance on that side measured .07. So that means the previous clearance was -.03. A bit tight... The left exhaust I went down one size, from 270 to 265 and it then measured .05. So it was at 0 previously.

Prior to the valve adjustment, the bike ran fine. I had adjusted the idle and it idled normally, I could get on the gas and it rev'd fine. I've just fired it up after putting everything back together after the valve adjustment, and it idles fine, but if I rev the throttle, it hesitates and either dies or just drops the revs enough to seem like it's going to die. If it doesn't die it then revs after a second or so.

What did I do? Ran fine before the valve adjustment and that's the only thing I've done since the last time I started it up. I would think this would be a carb issue but I can't imagine why that would show itself after a valve adjustment...

yeah i've been exeriencing similar things since my valve adjustment.  the general concensus from what people have been telling me was to check the carb balance, which i have yet to do

Stupid question, but would be an easy fix: Did you turn the tank petcock all the way back on... like perfectly up and down?  It's known to be a bit finicky and could be restricting fuel flow

How would swapping a few valve shims unbalance the carbs? Or have any effect on the carbs at all? I don't understand how there could be issues with the carbs after a valve adjustment unless it's a big coincidence, but I'm not all that knowledgeable about these things...

At first I realized that I had forgotten to turn the fuel petcock back on and I thought maybe that was the problem. Nope, still did it. Then I noticed some gas dropping onto the engine from the left carb and I thought maybe the fuel line had a leak or other issue. The lines were a little loose and had no clamps. So I replaced the fuel lines. Didn't do anything, except stop dripping fuel. I've sprayed WD-40 all around there and nothing happened so I'm not thinking it's a vacuum leak. I also got a nice backfire last time I tried to get on the gas.

That seems to leave nothing but the carbs... So I guess I have no choice but to break them down, clean em up and balance them?

Ok, tried to check the float levels. The right carb is normal, the left one I don't know, the drain screw is stripped and I can't get it loosened. Grrrr. I don't suppose that's a normal sized screw I can go buy at home depot?

Anyway the fuel was leaking when it was on prime, just noticed it again when tried to check the float levels and I was thinking maybe I had a stuck float but then I seem to recall reading that on prime it's normal to leak fuel (makes sense).

So, anything else I should do before tearing the carbs apart?

Quote from: debtman7 on May 12, 2007, 06:19:13 PM


I don't suppose that's a normal sized screw I can go buy at home depot?

IT SURE IS!  Alot of people swap that out.  I'll track down the size for you in a second

yeah those little screws suck, the srews that hold in the float bowls suck to, I would rather use some hex srews, I'll wait till TragicImage finds what size they are.

The size for the Allen Bolts are: M4x10 by 1/2" long METRIC   <<< Bowls



I'm working on the rest








***EDIT***

I might of spoke too soon.

Any idea how I can get the stripped drain screw out of the carb? They are in there majorly tight and I don't think there's enough clearance to get a screw extractor in, plus I'd be worried about doing some damage to the carbs with an extractor on such a tiny screw...

Today I'll pop the valve cover back off and recheck the valve clearances. If I can get the screw out I'll check the carb sync. Anything else? I'd really love to avoid taking the carbs apart, especially since I don't know if they are actually the problem.

[4

Ok, today I rechecked the valves. They were, of course, all different from when I got done last time. Not sure how, I even made sure to spin the wheel a few times to seat them fully. Apparently didn't work. One intake valve was over .10 mm but less than .15. Also the right valves, which I had managed to get a .04 mm guage in before, I no longer could. So I swapped things around a bit and got them all around .05 mm. I figured, hey, that must take care of it.

Nope. Fired it up and I get the same thing. This time I let it idle for 2-3 minutes and tried the throttle again and it did much better. Still got a very very slight hesitation giving it the gas ocasionally, but most of the time it rev'd fine and the more it ran the less it hesitated. But still when I first start it up, let it warm up 30 seconds or so and take off the choke, it dies or starts to die when I give it some gas.

So do I need to check the carbs? Or is that just a "normal" start up thing? I don't know what to do now, other than to clean the carbs and check the valve's again.

I also managed to get the float bowl screws open and the float hights were fine.

I'm wondering at this point if this is just the way the bike is, needing to warm up for a bit more? It's 70 degrees today but after 2-3 minutes it was better. I would think that if it was a clogged carb jet, vacuum leak, etc it wouldn't go away when it warms up. Then again I have clue so...

Any help?

Sounds like normal start up to me.  It take the bike like 10-15 minutes of riding to fully warm up.  I'd try that and see how it behaves

edit:  also, rejetting a stock bike will help the bike to run smoother more quickly

Quote from: manofthefield on May 13, 2007, 04:08:58 PM
Sounds like normal start up to me.  It take the bike like 10-15 minutes of riding to fully warm up.  I'd try that and see how it behaves

edit:  also, rejetting a stock bike will help the bike to run smoother more quickly

So, everyone's stock GS will die if you give it the gas with the choke off when it's been running less than a minute in warm weather? I'm not sure I buy that. And I'm pretty sure that it didn't do this before I did the valve adjustment.

On the flip side, I can't think of any reason why it would improve as the engine warms up. A clogged jet is a clogged jet, warm or cold.

Grrrr, I'm getting rather frustrated with this stupid thing.

     You really need to balcance those carbs.

      I did my valve adjustments early this spring then did the carb balance.I had re-jetted last year and thought it ran good.But after the valve adjust and balance...It's like a whole different bike.

    The reason for needing the re-balance is that by changing how the valves closed you changed how much vacuum the carbs are seeing. All those valves that were tighter than spec. were not sealing properly.You lose on both ends an open exhaust valve on the intake stroke loses vac. so not as much air/fuel gets into the cyl.,either valve open on the compression stroke and you lose pressure from the burn.

   I never checked mine last year.but they were so far out after the valve shims that it nearly sucked the fluid right out of my home made balancer.

  The balance of the carbs is based on the vac. they see otherwise if it was just a carb adjustment they could be done off the bike like.

  Try to balance them and see what happens.It's really pretty easy once you have some sort of gauge to check them with.

Quote from: Wrecent_Wryder on May 13, 2007, 05:12:37 AM

Quote from: TragicImage on May 12, 2007, 06:39:26 PM

The size for the Allen Bolts are: M4x10 by 1/2" long METRIC   <<< Bowls

Uh.. I don't think you're ever going to find a screw marked M4 (metric) x 1/2" (inches)... and I don't think 10 is right. In fact, if you keep reading that thread, I think it's contradicted later.

I use M4 x 0.7 x 12mm in stainless. The 0.7 pitch is by far the most common in that size, you're basically looking for M4 x 12.  Those work fine for all 8. I think Srinath said he used longer ones in the front, just for more strength.

The stainless ones aren't real cheap - 60 cents each, I think, and it's probably overkill.

yea, you're right.

Quote from: debtman7 on May 13, 2007, 05:58:00 PM

Quote from: manofthefield on May 13, 2007, 04:08:58 PM
Sounds like normal start up to me.  It take the bike like 10-15 minutes of riding to fully warm up.  I'd try that and see how it behaves

edit:  also, rejetting a stock bike will help the bike to run smoother more quickly

So, everyone's stock GS will die if you give it the gas with the choke off when it's been running less than a minute in warm weather? I'm not sure I buy that. And I'm pretty sure that it didn't do this before I did the valve adjustment.

Um, actually, yes. This is normal. Mine is stock and has always been this way, takes a good 1-3 mins to warm up, during which time I don't rev it with choke off. It will sputter.

Quote from: Shadow on May 13, 2007, 08:08:26 PM
     You really need to balcance those carbs.

I checked the float height using the clear tube on the drain hole method and they were both fine, wouldn't that indicate that they don't need balancing?

Well, about half the people I've asked say it sounds pretty normal, the other half say that I probably have a clogged idle jet and the reason it's better once it warms up is because the fuel vaporizes better and get get through the constricted opening better.

At this point I don't know. I think I'll seafoam it, then start riding it since we take the MSF course this week. See how it runs after that.

I remember reading something about just putting a washer somewhere to help with the idling, rather than doing a rejet, can't remember where I heard that though. Is that an option?

Also seafoam recommends adding it right to the carbs for a good cleaning. Basically what I've heard is that I should stick the fuel line into the bottle of seafoam and run it until the engine dies, then let it sit 5 minutes, hook the gas back up and then run the seafoam treated gas in the tank through it. Would that be safe to do?

     Carb balance has nothing to do with float height.

    Float controls how much gas is in the bottom of the carb bowl (ie how much is available to the carb at any given time).

    The balance adjustment was described to me once as a seperate idle for each carb.Not exactly right but close.Because we have two completely seperate carbs feeding two completely seperate cylanders each has it's own adjustments so they will ffed the fuel/air mix in at the same rate at the same time.

Quote from: Shadow on May 14, 2007, 05:32:00 AM

     Carb balance has nothing to do with float height.

    Float controls how much gas is in the bottom of the carb bowl (ie how much is available to the carb at any given time).

    The balance adjustment was described to me once as a seperate idle for each carb.Not exactly right but close.Because we have two completely seperate carbs feeding two completely seperate cylanders each has it's own adjustments so they will ffed the fuel/air mix in at the same rate at the same time.

Ok I'll give it a shot. Rather than deal with the t-connectors and such on the diy balancer (seems like it would be leak prone) can I just use one really long tube, hook each end up to the carbs with some water in the middle, drooped way down. Does that work? Seems like it would be less leak prone and simpler to do.