I have a 93 GS500E and I'm having some issues. Little history...I bought the bike a couple months ago and it ran like a dream. Always started first try and no choke was needed. Only issue was a petcock going bad and causing fuel starvation. Well, at the time, I didn't realize that was the issue so I immediately thought the carbs. I "rebuilt" them by replacing the needle valve assemblies and float bowl gaskets. When I was cleaning the carbs out, both needle jets were really clogged. I cleared out all the gunk and put them back together. Now, the bike is REALLY difficult to start and the choke appears to not have any effect. The bike will start and once I get it warm, it runs great the whole day, but getting it to start is quite difficult.
Now, as it sits today, I have installed a K&N lunchbox and full Vance and Hines exhaust. I have rejetted with 40 pilots and 147.5 mains. I did not use any washers and my idle adjustment screws are 3 turns out. The bike is still very tough to start. However, I have it to a point where it will start full choke, I immediately have to shut the choke off completely and then hold the revs around 1500 using the throttle. If I leave the choke on, even just barely, it dies immediately. If I let off the throttle, it will drop to around 900 rpms and then eventually die if I don't rev it every 20 or so seconds. Again, once I ride and get the bike warm, all is well and it starts the first try, no choke. Also, I have exhaust pop on deceleration. It doesn't always occur but it does more often than not. I believe this is due to running lean but when I compared my plugs to the pictures, they looked to be good.
Sorry for the novel, but I'm at my wits end. It's really annoying to have to go through so much hassle just to get the bike started. I know these machines are cold natured, but considering it started perfectly before I worked on the carbs, I'm willing to bet that I did something. Anyone have any insight? Surely I can't be the only one to run into something like this...right? :D
why didn't you use washers on the needles? Did you do a carb sync after putting the carb back together?
Quote from: ineedanap on June 09, 2009, 07:27:10 PM
why didn't you use washers on the needles?
Honestly, I forgot to pick them up and remembered them as I was putting my tank back on after the rejet. I made one of those DIY carb sync tools so I'm going to install washers when I sync my carbs. They look to be in sync but I thought I'd double check.
The wiki seems to be pretty spot on for jetting. I bet once you richen things up with the washers and sync the carbs it'll be running good.
Quote from: ineedanap on June 09, 2009, 07:35:41 PM
The wiki seems to be pretty spot on for jetting. I bet once you richen things up with the washers and sync the carbs it'll be running good.
That's the strange thing. Once the bike is warm, it runs like a champ, it's just really difficult to start. It was horrible to start after I cleaned the carbs and before the filter/exhaust.
When you move the clutch lever at the bar can you see the arm on the carb move?
Quote from: ineedanap on June 09, 2009, 07:48:52 PM
When you move the clutch lever at the bar can you see the arm on the carb move?
Yes. It's a nice, smooth movement and the cable appears to be in good condition with no kinks or issues.
Just occurred to me...I'm way overdue for a valve check. Think my shims could be worn and causing the issues?
A tightish set of valves will act up 5 seconds after startup. If its more than just a little tight, it will act like its sucking air, misfiring and popping etc etc till warm, when fully warm it can run almost normal. But it can at idle act like its hovering and slow to drop back to idle etc.
My guess though is that you screwed up @ rebuild.
Cool.
Buddha.
OK air screws supposed to be @ 3 ... not idle screws.
150 mains will be betterm dunno why you got 147.5.
Washer under the needle is prolly another one.
Then look for air leaks, and check your vlaves for sure. You're almost there. How is the float level ? Its prolly OK just check as you ahve it apart.
Cool.
Buddha.
Quote from: The Buddha on June 10, 2009, 07:41:33 AM
OK air screws supposed to be @ 3 ... not idle screws.
150 mains will be betterm dunno why you got 147.5.
Washer under the needle is prolly another one.
Then look for air leaks, and check your vlaves for sure. You're almost there. How is the float level ? Its prolly OK just check as you ahve it apart.
Cool.
Buddha.
I'm using the term idle screws generically, even though I shouldn't. My air idle adjustment screws are three turns out.
Washer(s) will be coming very soon, along with the valve check.
Float level is good. I did the test using the clear tubing and all is well.
Thanks for the info.
Update: One of the brass vacuum tubes on my carbs was broken where it meets the carb body. Turns out all of my issues were due to a nasty vacuum leak. I have that patched up until I can figure out a better solution for the repair and the bike is running like a dream. The choke works properly and starts first try, even when cold. Thankfully, all my shims were in spec so I'm good for another 4k. Thanks for all the advice that you guys have given.
That external brass tube ... oh yea you need a carb body swap.
Which carb ?
Cos I have 2 with the same carb body damaged, one with pilot and one with mix screw, heck I think I have 3 with the same body busted.
If your's is the other one, I'd sell ya the whole damn body for 10 and ship.
I could do the swap as well, but figure on being out a benjamin. Might as well add a rejet for 25 more if you will at that point.
Cool.
Buddha.
I need the right side. If you have a good one for $10 + shipping, I'll take it. Just shoot a PM my way.
I will look if there are good rights. Remember its the body only, most everything would have to be from yours.
Cool.
Buddha.
Not a problem. I really need a better fix than JB Weld...lol.
Quote from: larrimus on June 17, 2009, 11:09:08 AM
Update: One of the brass vacuum tubes on my carbs was broken where it meets the carb body.
Nice job finding the problem. :thumb: