cleaned carb still runs bad

[nejeff]

right.i bought another used carb of ebay.put it on and its doing the same.will idle ok for a wee minute then rise up to 5000 on its own.bliping the throttle will bring it back sometimes,bring it back to low and cut out.or not bring it back. it seems to be worse when engine is warm.boots have been checked and rechecked and have been spraying wd40 around while bike is running.at my wits end

What year is it? Are your points sticking (not opening)?

[skikman]

What year is it? Are your points sticking (not opening)?

its a 98 no points.cdi

[nejeff]

its a 98 no points.cdi

You turned out idle screw correct? Nothing is physically holding it open?

[skikman]

You turned out idle screw correct? Nothing is physically holding it open?

no its shut fully.this is the second carb and its doing the same thing so i take it that it must be something else.going to get a compression tester and see what that reads instead of just putting my finger over the hole.not sure where or what else to look at.

[gs11ezrydr]

Does the ignition have a mechanical advancer. If so are the springs ok? Is it opening and closing smoothly not sticking etc.? If the springs are weak it will run as you described.If no advancer how about a partially sheared flywheel key? Recheck the cam timing. Also if there is a vacume petcock that may be a source of a air leak also.How about the float bowl vent tube is it open to atmosphere not kinked,clogged,etc.

[skikman]

Does the ignition have a mechanical advancer. If so are the springs ok? Is it opening and closing smoothly not sticking etc.? If the springs are weak it will run as you described.

not sure.will i find it at the stator?

[Agemax]

not sure.will i find it at the stator?

it probably hasn't as it is electronic ignition. if it has it will be under the r/h engine ignition cover.

[gs11ezrydr]

Your right I looked it up and it has a single pickup coil inside the stator cover mounted out side the flywheel. My GS1100 has electronic ignition also and it has a mechanical advancer is why I asked that.Not sure if you could even hit yours with a timing light and watch what is happening.At least without making a mess. With two carbs doing the same thing leads you to think elsewhere hum.I didn,t see a vacume petcock,or a push pull throttle set up either.If the cam timing is correct and the valves are adjusted properly.I'm leading towards the low compression as stated earlier.I am on the Suzuki dealer web site looking at various parts fiches now lol.I'm a Suzuki mechanic for a local dealership here in Ky.So hopefully i may help you in some way and straighten this little gem out for ya. Gettin a little late here and not thinking just right

[skikman]

Your right I looked it up and it has a single pickup coil inside the stator cover mounted out side the flywheel. My GS1100 has electronic ignition also and it has a mechanical advancer is why I asked that.Not sure if you could even hit yours with a timing light and watch what is happening.At least without making a mess. With two carbs doing the same thing leads you to think elsewhere hum.I didn,t see a vacume petcock,or a push pull throttle set up either.If the cam timing is correct and the valves are adjusted properly.I'm leading towards the low compression as stated earlier.I am on the Suzuki dealer web site looking at various parts fiches now lol.I'm a Suzuki mechanic for a local dealership here in Ky.So hopefully i may help you in some way and straighten this little gem out for ya. Gettin a little late here and not thinking just right

i hav'nt checked the cam timming yet.im wondering could it be a tooth out?would that cause the bike to run like this?will i have to take the head off to check?will get a look at it later.bit busy with kids over weekend.thanks for your help

[chuck hahn]

Have you went to basscliffs website and downloaded a service manual yet? If not, do so. You can check cam timing just by removing the cam cover and aligning the timing mark at the points cover and checking the timing marks on the cam sprockets.

[skikman]

dam.i was kinda hoping it was a tooth out but everything lines up ok.i got a compression tester but will need a smaller adopter to fit the plug hole.another day with no result

[gs11ezrydr]

Back on post #19 you said no its "shut" fully. If that is correct there lies the problem. Or even if not. Try this.Close the mixture screw off which is seat it lightly then "open" it up approx. 2 - 2 1/2 turns out make sure the throttle cable has plenty enough free play. Back the idle speed screw down.Make sure you are not turning the idle speed screw up too high holding the butterfly open too much.Play with the mixture screw until the highest r.p.m. is obtained while dropping the idle speed adjusted down at the same time.I have had several single cyl. engines act as yours is and this is how I have corrected it.Good Luck

[skikman]

Back on post #19 you said no its "shut" fully. If that is correct there lies the problem. Or even if not. Try this.Close the mixture screw off which is seat it lightly then "open" it up approx. 2 - 2 1/2 turns out make sure the throttle cable has plenty enough free play. Back the idle speed screw down.Make sure you are not turning the idle speed screw up too high holding the butterfly open too much.Play with the mixture screw until the highest r.p.m. is obtained while dropping the idle speed adjusted down at the same time.I have had several single cyl. engines act as yours is and this is how I have corrected it.Good Luck

sorry i meant that the idle screw was back fully for the butterfly to shut fully.this is when it is reving up on its own.blip the throttle and it will come down and cut out.ive had the mixture screw at 1,1-1/2,2,2-1/2-3,3-1/2 out making no difference what so ever.i can fiddle about and get it to idle for a minute or 2 then it just revs up on its own.i have done everything i can think of with the carb.and remember this is the second carb off a running bike and i still have the same problem as i did with the first carb.so it must not be a carb problem.but what??????

[gs11ezrydr]

How is the fuel supply to the carbs. Petcock flowing freely.Fuel tank vented properly. Are you attaching the same bowl vent tubes to the carbs that are poss. clogged.It almost sounds like they are filling for a min. or two then the level is getting low and starving the pilot jet.Leaning out.Since both carbs acted the same it might be because they are being hooked up the same way.Still thinkin here lol.We have a moto at our shop if we can't fix it we will buy it. We have not purchaced any so far.So how much were you wanting for this one?? What is the spark plug looking like? White, Black, Tan.

[skikman]

How is the fuel supply to the carbs. Petcock flowing freely.Fuel tank vented properly. Are you attaching the same bowl vent tubes to the carbs that are poss. clogged.It almost sounds like they are filling for a min. or two then the level is getting low and starving the pilot jet.Leaning out.Since both carbs acted the same it might be because they are being hooked up the same way.Still thinkin here lol.We have a moto at our shop if we can't fix it we will buy it. We have not purchaced any so far.So how much were you wanting for this one?? What is the spark plug looking like? White, Black, Tan.

the plug is nice and tan.fuel is flowing ok.i took the peatcock off and cleaned it.i have clear vent tubes on and there is no dirt.i have noticed that there is a slight backfire after reving it up.starting to think that its a timming issue maybe,not sure,dont know,i give up.looks like i will have to take it to a mechanic £££££