I don't get it folks, what does a valve adjustment have to do with carb syncronization?  Sure glad I don't get it because I've never had to sync carbs in over 120k miles of GS500 riding and over 350k miles of total riding.  And I've done a dozen GS500 valve check/shim jobs.

I keep my carbs clean by running gas thru them every day possible and I keep my carbs synced by not messing with them.

A stock 96-97 GS500 needs bit of warm-up before it will take the throttle, more than a 01 and later does.  No problem for me, I'd pull the old 97 GS out of the garage running while I put my gear on and closed the garage and then ride off with the choke still on a bit for up to a mile in warm weather and maybe a bit longer in cold weather.  Close the choke a bit after it's started and running and a bit more before riding off and then close completely after a short distance. 

Works for me.

   Have you checked to see if your carbs are in sync? Or are you just assuming they are because the bike runs O.K.?

  As I stated before I THOUGHT mine ran fine last year.I did the valve adjustment because I know the PO did not keep up an the preventative maint. I checked the carb balance after for the same reason.Hind sight is 20/20 if I'd have know the difference the two made I would have done it last year.Hard to describe the difference.Smoother more responsive.

  Mine after the above maint. and the recommended re-jet for stock airbox/stock exhaust fires on the first or second hit from cold with only about 1/4 to 1/8th choke. Most days at the first traffic light about 1 mile from home I have to shut the choke down to keep her running.Last year after re-jet before valves/balance it would roll over probably 10 times before firing and I rode the whole 5 miles to work with the choke on regardless of air temp.

  Make you own decisions if the carbs did not need to be balanced then ther would not be an adjustment for it on the carbs.Take a look at an old RZ-350 or a Banshee ATV where the intakes are connected with a crossover pipe.Both carbs see vac. from both cyl. therefore no need to balance and yep you guessed it no adjustment screw on the carbs.

Quote from: gsJack on May 14, 2007, 06:59:24 AM
I don't get it folks, what does a valve adjustment have to do with carb syncronization?

Changing the clearance changes the amount of volume that cylinder can pull (you're changing the amount of time the valve stays open).

Don't want to synch your carbs, don't do a valve adjustment.

Don't want to do a valve adjustment...double up on your oil changes to keep fresh oil in there (that would be every 2000 miles).

How old is your engine? I wonder if your valves were used to the old tolerances and now you need new valves... but I'd first synch the carbs... valves are among the things that could behave differently once hot. just my 2 cents.

Quote from: Shadow on May 14, 2007, 08:25:07 PM
Make you own decisions if the carbs did not need to be balanced then ther would not be an adjustment for it on the carbs.Take a look at an old RZ-350 or a Banshee ATV where the intakes are connected with a crossover pipe.Both carbs see vac. from both cyl. therefore no need to balance and yep you guessed it no adjustment screw on the carbs.

The adjustment provisions for carb sync are necessary to get them set up initially so both throttle plates are timed together between the two carbs.  Once set up properly there should be little or no need to mess with this adjustment further unless you or a previous owner screwed it up.

I wouldn't consider it part of a valve adjustment, restoring valve clearance to original correct clearances should bring it back to where they were when the carbs were initially synced. 

Quote from: scratch on May 14, 2007, 08:54:55 PM
Changing the clearance changes the amount of volume that cylinder can pull (you're changing the amount of time the valve stays open).

Don't want to synch your carbs, don't do a valve adjustment.

Don't want to do a valve adjustment...double up on your oil changes to keep fresh oil in there (that would be every 2000 miles).

Yes, changing valve clearances does change valve timing a bit, but in the case of routine valve checks you are restoring valve clearances to their original settings and valve timing to where it was when the carbs were synched.

Valve clearances need to be maintained properly within reason since tight valves can cause poor idling when cold and even burnt exhaust valves in extreme cases, and loose valves can be noisy and even make thrown shims more likely in extreme cases. 

I never synched the carbs on the 97 GS and didn't notice any difference in it's running over 80k miles and the carbs went untouched.  Likewise, the 02 GS has about 48k miles on it now and never ran better and both bikes got their valve checks/shim changes.

I think 2k oil changes are about right for an air cooled motorcycle engine that runs the tranny in the engine oil.   

Well, I decided to pull the carbs. Mostly since I figured it would be good to learn how to do it sooner or later, and also I'd like to start riding this weekend without having to worry about what shape it may or may not be in, so I just went for it.

They look pretty spotless to me. Here's some pics:





That's as far as I've broken them down, looking that clean is there any point in tearing them down further?

Not a sign of any crud, this is fresh off the bike no cleaning at all. The jets, I don't know, how do I tell if they're clean? The hole is *tiny* so I can't really see if there is crud in there or not. I can hold it up to a light and see a small circle. The bowls are clean. That would lead me to believe that the jets are probably not clogged.

So, looks like it is in fact just normal gs behavior. I'm going to call around and see if I can locate some #40 pilots and #125 mains and do the stock rejet, however I'm having my doubts about finding those locally. Maybe I can find someplace nearby that can overnight them not too expensively (really want to ride this weekend). If not I'll just keep the stock jets in there.

Sweet, found a place up in cleveland that actually had jets in stock (every dealer within 30 minutes doesn't stock them), they ship via UPS which means they should be here by tomorrow evening. $27 for two pilots and two mains with tax (in state, grrr) and shipping. I don't know how that compares to sudco but you can buy them individually, so if anyone else on the east coast needs some, they'll get here sooner than all the places out in cali.

http://www.carbparts.com/

Website sucks, no online ordering, but I get my parts tomorrow.