I want to start off by saying "Hello Everyone!" and make it clear that I have some general knowledge of mechanics, and an interest in bikes, but no real knowledge of motorcycle mechanics.  I am learning this as I go along and a lot of what I have done so far was pulled from here or the GS500 wiki.  So here's my story:  Last year I took the MSF course and got endorsed.  I've only been on a few bikes before this and following my endorsement I got two bikes for about $1000 total.  A 1992 GSX600F Katana that had been sitting for about 5 years and a beat up 1995 GS500E that was running quite rough.  My first priority was to get the GS500E running.  This thing was all banged up, head light held on with electrical tape, tire bald, left rear faring busted, frame above the rear tire is tweaked, rear brake had no pressure, etc. etc.  So I fixed a lot of little things in so far, which I am going to skip over for now.   What I do wanna mention is that the bike seems to run rather lean, with some popping on deceleration.  I changed the oil and upgraded to iridium spark plugs.  I cleaned the carbs, put two shims (M3 washers) under each pilot needle, replaced the fuel lines and the vacuum line to the petcock (which by the way does not work worth a darn except in prime position, but I read in this forum that seems to be normal for this particular petcock), Turned the idle mix screws back to 2 turns out (this is where there seems to be the least popping).  The bike definitely responds a lot better now, and only seems to pop occassionaly now (mainly when accellerating quickly then backing off the throttle).  This bike does have an F1R exhaust on it and I doubt the previous owner every put new jets in.  Is there anything I can do about this popping? 

On a side note, I was also wondering how much of a difference progressive springs would make and what grade fork oil I should use?  The forks are very soft and make me feel a little uncomfortable when riding hard. 

Last one I swear!!!    Is it possible to get the Faring from a GS500F on the GS500E?  I do not really like the streetfighter look myself.

A lot of people will tell you that upgrading the fork springs is the best mod for this bike.  I finally took the advice and ordered some race tech straight rate springs.  I haven't put them on yet, but I hear the difference in handling is amazing. I'm going to use 15w fork oil when I swap out the springs.  I weigh 185 without gear and I went with .85's.

You really should rejet the carbs; the GS is notoriously lean, and the less-restrictive exhaust canister only makes the problems with the idle jetting WORSE. Install #40 pilot jets, and work from there. You might have to remove one (or both) of the washers you've installed if the bottom end response (just off-idle) gets worse, but rejetting is the ONLY way to eliminate the lean conditions, and the bigger pilot jets will help a lot. Of course, since you'll be ordering pilots, you should buy new mains as well, so you can kill two birds with one stone.

Progressive Suspension springs are a great choice for street use; unless you're a paperweight, you should use 15-wt. fork oil. If you're less than 150 pounds in full gear, and NEVER carry a passenger (or gear on the back, or in saddlebags), you could use 10-wt. fork oil instead. If you do ride with a passenger, or tip the scales at 150+ pounds, use 15-wt. fork oil. Measure it CAREFULLY; overfilling the forks by a small amount will give a harsher ride; REALLY overfilling the forks will result in hydraulic lock, and you won't enjoy that at all...

Installing the 500F fairing would be both expensive and aggravating; if you really want one, fix your motorcycles, then sell them, and buy an F model instead. Chances are, you can find a buyer for your "E" in these forums, once you finish fixing it.

I would refer to the Wiki for jetting info for the type of air filter you are running and performance exhaust.I upgraded to Progressive springs and 15w oil.I'm 200lbs and it's great.As far as the petcock,I'd mod it to use no vacuum.Here's da linky. http://gstwins.com/gsboard/index.php?topic=19363.0

Wow, thanx everyone for the quick responses.  Well it's still popping on decel and the idle seems to randomly rev way up... I can get it back down by letting the clutch out just to the friction point maybe a little farther and sometimes it stays down and sometimes it jumps back up.  I read somewhere else that may be a sign of vacuum leaks.  Does this sound right? 

Thanx for the advice guys, I definitely upgrade to the stiffer springs and maybe I'll just order the jets rather than keep trying to tune it out (since it sounds like no amount of tuning is gong to get rid of this lean condition anyways, lol).  The fork seals look like shaZam! tho and are starting to show some rust so I definitely need to get new fork seals and oil, might as well put the new springs in then.  Are progressive springs a bad idea?  I noticed you said you got the straight ones......

If it is a vacuum leak I am guessing it is in between the carbs and airbox or carbs and head....  any suggestions where I can pick up those boots cheap?  Heck any suggestions where I can get a reasonably priced jet kit and new springs? 

You're on the right track looking for vacuum leaks; start with the carb intake boots, which are the black rubber parts between the carbs and the head.

Again, Progressive Suspension springs are a great choice for STREET use; they're cheaper than the Race Tech straight-rate springs, and if you don't like them for some reason, you can always sell them here, then buy the Race Tech springs. I've installed a Race Tech front suspension on a few other motorcycles, but I ran them on the track only. There's nothing wrong with straight-rate springs; the basic difference is, progressively-wound springs are actually a compromise between two different spring rates. The lower part of the spring is "softer" than the upper part, to provide a good all-around ride on varying surfaces (city streets, superslab, whatever). Straight-rate springs are just that; they provide a single rate of front end compression, which is (IMO) better suited for the racetrack. If you want a bargain, get a set of Progressive Suspension springs; if you are willing to spend a few more bucks, buy the Race Tech springs. Your money, your motorcycle, your choice.

Lastly, you're wasting your time trying to compensate for the stock jetting, unless you want to drill out the pilots and mains, but why bother? Replacement jets are cheap compared to all the time and energy you'll spend trying to save a few bucks. Invest your time and money in new jets, and do NOT bother with any of those stupid jetting kits; they are a BIG waste of money, and don't work as well as simply replacing the pilots and mains, adjusting the air-bleed screws, then balancing the carbs. Avoid the Dynojet and Factory kits; instead, roll your own jetting. You'll save your time, your money, and your sanity.

GSNoober said #40 Pilot Jets, what size do you guys recommend for the Main Jets?  And where can I buy the jets themselves?  Wouldn't I also need new needles?  Thanks so much!!!!!

I've been reading all day (what else can u do at work? lol)  and I see the general recommendation for road use is 40 and 150 jets.  Also if I order the mikuni jets I don't need to get a different needle or change anything else it seems, so Mikuni it is.  Thanx again guys!!!

Quote from: Rom30 on March 18, 2008, 03:42:55 PM
I've been reading all day (what else can u do at work? lol)  and I see the general recommendation for road use is 40 and 150 jets.  Also if I order the mikuni jets I don't need to get a different needle or change anything else it seems, so Mikuni it is.  Thanx again guys!!!

You'll need to add 1 or 2  #4 washers under the needles.

Quote from: Rom30 on March 18, 2008, 03:42:55 PM
I've been reading all day (what else can u do at work? lol)  and I see the general recommendation for road use is 40 and 150 jets.  Also if I order the mikuni jets I don't need to get a different needle or change anything else it seems, so Mikuni it is.  Thanx again guys!!!

The wiki is your friend:

http://cgi.stanford.edu/~sanjayd/gs500/Upgrades/Rejetting

More to learn about:

http://cgi.stanford.edu/~sanjayd/gs500/Upgrades/Rejetting-LeanOrRich?

Tutorial mentioned in the wiki:

http://www.angelfire.com/mt2/mikesgs500/rejetting/

Wiki Home Page:

http://cgi.stanford.edu/~sanjayd/gs500/

You can buy new jets from Sudco, as mentioned in the wiki, or maybe someone here will have an extra set for sale; once you know which sizes you need, it won't hurt you to post an ad in the "For Sale" forum...

You do NOT need new needles when rejetting; don't even THINK about changing the taper (by sanding or grinding them), because even a MINOR change to the taper of the needle can make a BIG difference in the carburetion. The Mikuni engineers designed the taper to work properly; it's the jetting that makes the engine lean, so correct that by installing new #40 pilots, and #125 mains (for a STOCK setup), unless you're NOT going to use the stock airbox and exhaust. If you're using anything from the aftermarket (K & N lunchbox air filter, for example), POST THAT INFORMATION HERE, and we'll advise you on the proper pilots and mains.

Understand that jetting is affected by altitude, temperature, humidity, and barometric pressure, among other variables. Even the type of fuel (regular gasoline as opposed to E85, for example) affects engine performance, and E85 would require MUCH larger jets than pump gas. You're trying to set your carbs to work best in your environment; just-right jetting at sea level (in Boston, for example) would be too rich if you were running up Mt. Evans Road (more than 11,000 feet above sea level) from Idaho Springs, outside of Denver... You can't learn everything in one day; jetting is almost as much of an art as a science; if you'd ever seen an engine tuner reading a spark plug with a jeweler's loupe, you'd know what I mean... No, I don't use a jeweler's loupe; I'm not prepping race engines.

Let us know what your basic intake system is (stock airbox, NO airbox, K & N pods, Unifilter, K & N lunchbox), along with your exhaust system (stock, aftermarket headers and pipe, stock headers with aftermartket can), and we'll try to get you into the right ballpark.

Also, get familiar with the jetting matrix; I'm not a big fan of it, but others here swear by it. As long as your valves are properly adjusted, your petcock is flowing fuel, the float levels are correct, and your fuel hoses are routed properly when you finally begin rejetting your carbs, you shouldn't have any major problems. Too many people think that "fixing" the carbs means ONLY swapping jets, but that isn't even close to the truth. For example, the throttle cable(S) need to be adjusted and lubed; the carbs need to be balanced; the carb diaphragms need to be in good condition, along with the other rubber components; the floats need to be set to the proper height... you get the idea. Take this one step at a time; learn as much as you can BEFORE you begin this, and you'll avoid the "MY BIKE WON'T RUN! WHAT DID I DO WRONG?" posts that give so many of us nightmares.

Start reading, start learning, and ask questions for clarifications of things you don't understand. I'm old and slow, but I got that way because I learned (the hard way) when NOT to rush things back when I was less than half the age I am now.

Ok, so it has what appears to be the stock headers with an aftermarket slip on, a Cobra F1r to be more specific.  Along with the jets I was planning on ordering the K&N pods, new boots and o-rings (the ones between the carbs and cylinder head, they seem to be leaking, i.e. spraying brake cleaner on them while the bike is idling makes the exhaust go white and the idle floats high during normal operation), progressive springs and 15 wt oil and fork seals (I'm 170 without gear).  Sounds right?  Oh, and I live here in Tampa, FL so the elevation is  a whopping 48 ft!    

Sounds good.I'm 200lbs in my gear and progressives are great on the street.

So I got everything in and before I could install anything I had a spill on my bike.  Really lazy turn, open road.  There was a little dirt on the road and I just overcompensated when I hit and slid to the outside edge, where the grass was higher than the street and the bike flipped and thru me a few feet.  No major injuries.  Headlight cover and right turn signal broke. A lot of dirt on the bike.   Went down on the right side.  Runs fine, although the handle bars do appear to be tweaked just a little.  I drove it home after work (still had to work after spill lol) and everything seemed fine.  I straightened the headlight bucket (tho there is no glass in it now) and super glued the turn signal cover back on.  Good enough for a sunday ride I figured.   So I figured I'd start installing the parts I had ordered.  Replaced the rubber boots for the carbs (had an air leak in the old dry cracked ones, but the new lunchbox filter on (figured it match the cobra exhaust lol), and installed the jets (147.5 mains and 40 pilots).  I noticed a small metal cylinder with angled o-rings was loose in one carb (I believe it is part 33 on this fiche)  and now that I have the bike back together it is idling HIGH!  I backed the idle screw out all the way, and the idle mixture screws to 4 turns and back up to 1/2 turn.  I also tried putting 2 m3 washers under each needle, 1 washer, and no washers.  It makes no difference the idle remains high.  So high in fact that the bik actually revs too high in first and second with no throttle!  I forgot to check for leaks again after installing the boots and still need to synch the carbs.  I wa sjust wondering if anyone had any idea what might be going on?  A search on the internet turned up something about worn advance unit springs?  Any suggestions on what to look for would be great!!!  I wanna get this bike running first and fore most, then strip it down to the frame and make it pretty again.  Thank you again!

Check the adjustment of the throttle cable.  It should let the throttle return all the way to its idle setting and should remain there as you turn the handlebars. 

My guess is that you have no slack at the carb (where you disconnected it to remove the carb).

Finally got everything in order.  Small o-rings in the top of the carbs were missing.  >.<
Replacing the fork seals and putting the new progressive springs and 15wt fork oil in this weekend.  Now I just need to fix all the aesthetic pieces.  Broken head light, no gauges, cracked faring, and a dented gas tank. 
She runs great though!!!  Just need her to look the part!

When are you gonna post some pics?  We don't care if she's in bad shape right now.

Lol, hadn't really thought of it.  I guess when ever I see some sun this week.  Stoopid rainy season.  Stoopid florida showers. 

It's been a minute so I thought it was time for an update.   The bike is still aesthetically revolting lol.  Mechanically, well, since rejetting and installing the springs and fork oil, lunchbox air filter,  and iridium plugs she's been pretty good to me.  I drive her every day 44mi round trip to work and back.  Couple minor issues to work out.  Idle is erratic.  Somedays she idles perfect, usually colder days, and some days the idle hangs until I give it some resistance (brake and slow off the clutch).   I'm guessing too rich still?  Need to mess with the idle screws again.  On the road she runs great.  Died on me once across the courtney campbell bridge, at full throttle, top speed.  Fuel Starvation I'm guessing?  Still usingg the stock petcock which it seems has many faults with the vacuum feed system.  I usually just turn it to prime and run the bike like that.  Will get some pictures this weekend.  I have gauges and brackets coming from another member here on the forums.  Hopefully a headlight assembly also (all the glass is busted out of mine from my accident).  going to need a new rear tire soon, Will probably just gets tire on my katana and ride that instead, now that the bike runs, I realy want to strip it to the frame and repaint it.  It's showing a little rust.  I know I'm putting too much time and effort into this thing, but I'm not putting much effort.  After it was running my wife got on and took it around the block.  She likes it so much more than my big heavy 600 sport-tourer.  So looks like we're fixing it up and keeping it!  I think I need to check valve clearances and inspect the head gasket while I have the engine out also.  It's gonna be a project, but in the end we'll have a beautiful almost 20 year old bike, still running strong.  (Oh I forgot, I stole a couple parts of my Katana.  It's an older Katana, has a gixxer 750 in it,  but sleeved down to 600.  So if anyone was wondering, The carbs appear to be identical other than 4 vs 2 on the two bikes, I used the slider assemblies, rubber diaphragm, and plastic covers from the Katana's carbs.  Also, the rear tire on the gs500 is an old used tire off the katana.)

Plans for the GS500 (time and money permitting):
Need to replace the Headlight and install gauges!
Repaint frame.
replace seat (the ducati seat I seen on another forum member's bike looked very nice, but I also like the r1 rear end... hmmmm...)
I'd like to put the bandit rear tire and swingarm on if I can find them cheap.
Targa faring and air dam.
try to get the dents out of the gas tank or get a new gas tank
replace rear farings
repaint plastics and tank

just wanted to whine about pictures.

that is all.

men are visually stimulated creatures, ya dig ?

Welcome!