1st tech question for my GS550E

[Anonymous]

Greetings;

I have the bike running, but not as well as it should. It runs a little smoky, and after I let it idle for 10-15 mins it dies, but fires right back up. The smoke is a grey color. I was able to solve the rattle that I thought was the cam chain tensioner. I tightened the nut that holds the knurled knob on...the knob was vibrating. I tried adjusting the mixture screws per some previous posts...all the way in and then back out 2 1/2 turns, right? The air box lid is missing and the filter needs cleaning. What should I use to clean the filter, and does the lid make a difference? Thanks!

Charles

[Anonymous]

Re: 1st tech question for my GS550E

The air box lid is missing and the filter needs cleaning. What should I use to clean the filter, and does the lid make a difference? Thanks!

First, let me ask you to tell us what bike it is. That will help the more knowledgable among us to answer your other questions.

For my part, I will say that having the airbox all together is pretty important on these bikes. They are sensitive to the amount of resistance (and thus vacuum) created on the intake side.

If you have a foam filter (which I assume is what you're talking about, I don't know a good way to clean a paper filter), you can use kerosene or gasoline to clean it. The foam filter is "loaded" with oil, which works to catch dirt. The gasoline will dissolve the oil and pull the dirt out with it. Once clean, let the foam element dry and squeeze in fresh oil. Very messy!

[Anonymous]

Thanks for the reply! Sorry about that, the bike is a 1978 GS550E. Yes, the filter is the foam type. Do you think the lid is available from the dealer? I found an air box assembly on eBay that I will bid on just in case, though.

Charles

[KEITH KRAUSE]

The missing lid will lean the mixture out too much. Seal the lid opening with duct tape until you find a replacement lid. I'm not sure what "mixture" screw you adjusted 2 1/2 turns out? The correct part names for your VM carbs are the pilot fuel screw (underneath and engine side of the float bowl) and the side air screw. The pilot fuel screw is GENERALLY 1/2 to 1 1/4 full turn out from LIGHTLY seated for a stock bike. Start by setting them at 1 full turn out and go from there.
The side air screw is adjusted by using the "highest rpm" method.
They are GENERALLY 1 1/2 to 1 3/4 turns out after final adjustments.
Turn them out 1 1/2 turns to begin. Warm up the bike on the centerstand. Adjust idle to 1,100 rpm's with the idle adjuster knob. Starting at any carb you like, slowly turn the side air screw in either direction from the 1 1/2 starting point. Listen for the rpm's to max out. After fine tuning the screw for highest rpm, turn the idle down to 1,100 rpm by using the idle adjuster knob. Then repeat this with the next carb until all 4 are done and the bike's idling at about 1,100 rpm's.

[Anonymous]

Hi Keith;

Thanks for the clear reply! I adjusted the air screws on top of the carb...and too far it sounds like! I will try all the suggestions you have made. Hopefully I can get a lid for the air filter box.

Charles

[TheNose]

The missing lid will lean the mixture out too much. Seal the lid opening with duct tape until you find a replacement lid. I'm not sure what "mixture" screw you adjusted 2 1/2 turns out? The correct part names for your VM carbs are the pilot fuel screw (underneath and engine side of the float bowl) and the side air screw. The pilot fuel screw is GENERALLY 1/2 to 1 1/4 full turn out from LIGHTLY seated for a stock bike. Start by setting them at 1 full turn out and go from there.
The side air screw is adjusted by using the "highest rpm" method.
They are GENERALLY 1 1/2 to 1 3/4 turns out after final adjustments.
Turn them out 1 1/2 turns to begin. Warm up the bike on the centerstand. Adjust idle to 1,100 rpm's with the idle adjuster knob. Starting at any carb you like, slowly turn the side air screw in either direction from the 1 1/2 starting point. Listen for the rpm's to max out. After fine tuning the screw for highest rpm, turn the idle down to 1,100 rpm by using the idle adjuster knob. Then repeat this with the next carb until all 4 are done and the bike's idling at about 1,100 rpm's.

I love it!!!! Precise, clear instructions.

Terry

[Anonymous]

10 to 15 min seems kike a pretty long time to sit still with eng. on. The engines are cooled by air flowing across the cooling fins. Just to let you know to be careful, not to let the eng. get too hot. A fan blowing on the engine would be a good idea. It will make the bike feel like you are going down the road & the wind is cooling it. Not near as bad now as in the hot summer. Just be aware.

[Anonymous]

Thanks for the cooling tip...that never crossed my mind! Well, I did everything Keith said expect for the duct tape (don't have any) and the bike still won't start. I'll get some tape and try again.

Charles

[sv650]

Re: 1st tech question for my GS550E

If you have a foam filter (which I assume is what you're talking about, I don't know a good way to clean a paper filter), you can use kerosene or gasoline to clean it. The foam filter is "loaded" with oil, which works to catch dirt. The gasoline will dissolve the oil and pull the dirt out with it. Once clean, let the foam element dry and squeeze in fresh oil. Very messy!

Place the clean filter in a large ziplock (TM) freezer bag with a little oil. Exhaust air. Massage oil into filter, let excess drain to a corner of the ziplock (TM) bag, remove filter, and install in bike. Virtually dripless!

SV

[KEITH KRAUSE]

Your foam filter should be cleaned with a mild detergent that cuts oil/grease. Dish soap or a "409" cleaner will work fine and won't eat at the foam over time like gas will. Gas is bad for the hands and the brain too.
Spray on cleaner or dip the filter and squeeze out until the filter's clean. Air dry only to extend the life of the foam. Apply the filter oil according to the filter makers info or the filter oil info.
There's probably other things that need checking than just adjusting your fuel/air screws. We don't know much about the bike except it won't hold an idle too long and it smokes. When you rev the bike does the exhaust look dark or black? What color are the plugs? Any fuel leaking from the carbs anywhere? If you try to run without a filter at all, does it run better? What rpm's does it idle at when warmed up compared to cold? What things have you done to try to fix the problem? Any history about the bike may help too.

[Anonymous]

Again Keith, thank you! The bike was just putting out a light grey smoke from the exhaust when idling and the smaoke was the same color but a little heavier when revved. All four of the plugs have a sooty look to the tip and electrode. There is a strong smell of gas around the bike and I think there may be a slight fuel seepage from the bowl on the #4 carb. When I could get it started it idled around 2500 RPM cold and I adjusted the idle screw after it warmed up to around 1500 RPM. I have only tried what I read here so far to fix the problem as this is the first bike I have had to try and do some work on. The only history I have is that the guy I bought the bike from said it was running until about a month ago and he just bought a new bike rather than fix up this old one. It also has the right peg bent and the brake pedal was bent, so I assume the bike was tipped over on that side.

Charles

[KEITH KRAUSE]

Well, your problem could be a lot of things. Do you have a manual and basic knowledge to try to repair the bike?
The grayish smoke still has me wondering if you're running rich or also burning oil. I'm guessing you're running rich. Possible weak spark too, but usually all 4 don't become weak together.
If you get a decent blue spark with a new plug inserted in each plug cap, I'd try the basics.
Clean the air filter...tape off the lid opening...clean/replace/gap the plugs...check ignition timing and clean the points if you still have them...turn the idle down to 1,100 and set those side air screws...adjust the pilot fuel screws to about where I said...synch the carbs with a vacuum tool...clean the carbs or at least remove the floatbowls and flush the float valves out...replace the manifold o-rings and check the manifiolds for cracking...check the tank for rust too...check the petcock for correct operation/fuel flow... check the vacuum line...
A lot of stuff, I know, but believe me there's more. These are all basic maintenance things that can cause problems like yours, especially in combination. It may be possible you need a complete carb rebuild too if these things don't fix you up.

[Anonymous]

I have a Cylmer manual (got outbid on the Suzuki manual on eBay), and very basic mechanical skills (do some basic things on my cars like brakes). I did win an air box with lid, though. I haven't been able to get it to start since I posted this thread The fuel tank has some rust on the outside, so it probably has rust inside, too. It seems to me that someone would make a plastic or fiberglas tank by now.

Charles

[KEITH KRAUSE]

Well, like I say, your bike probably needs some basic maintenance done.
If you check off the things I said, the bike should be fine.
The bike could have other issues that can cause problems, such as someone altering the jetting, or low compression, etc, but the basics should be done in any case.
We can help you with carb rebuilding, etc, if it comes to that. Basics first.

[Anonymous]

I understand what you are saying, Keith. I do plan to do just that...check off the complete list of things you mentioned to take care of. It may take me a while to get it done, though. I'll keep in touch and let you know my progress.

Charles