Carbs knock, idle problems etc

Its funny, I pressed the button called new topic although this is probably an old old old topic. Anyway, here it is, Il spell it out some and then answer with all I have read. Please toss in your thoughts. I bought an 81. Unbelievable bike. Starts perfect. Looks perfect. No rust, very minor paint blemishes. 1 owner. 25k on the clock. All work was done. Oil, plugs, plug wires, timing belts, carb rebuild kit etc. Here is the thing. It wont idle, well, it will if I set it at about 2k. any lower and it wants to die and any lower also gives me a hideous knocking sound. Also, left side headers are only warm, not hot. right side headers hot as @#&% Read through as many forums as possible. So, first ran straight seafoam until engine wouldnt run. Let it sit for 2 days, started up with regular gas and after about 20 minutes of smoking like crazy it ran much much better. Not perfect. I can get the idle lower to about 1400 with no knocking but below that, still knock and die. Step 2. Carb sync. It was way way off. well first i noticed that the vacum screw on #3 was completely missing when I went to attach the vacum meters. Well, the sync was way off. It took a while and a great deal of finesse but, ive got it near to perfect as I could ever imagine. Idles much better and I can get it down (once the engine is warm) to around 1100. Any lower and I hear knock knock knock and engine wants to die out. But as I sit and rev the motor (which sounds perfect when I do) the idle will move up to 2000, then back down to 1100 then up to 1500 then down to 900. Well, bottom line is. it wont sit still. it only knocks when the motor wants to die but not always because it idles so erratically. I think from what I have read is that most of you will tell me to remove the carbs and run a wire through the idle jets because 1 or more is probably clogged. (yes the bike sat for long spells before I purchased it but the rebuild kit was put in several months before I purchased it and not ridden much after that point. So, here we are. how far should a guitar wire go in to know if I got it cleaned out? Any tutorials on cleaning idle jets? tutorials on removing carbs? Any thoughts would be appreciated.

Well it sounds like the bike is a real keeper, just need to sort out the carbs.

I'm not familiar with the guitar string reaming with what size and all but I think others are.

Yep, the idle jets are clogged. The knocking is from your engine being out of balance at idle (left to right) and the knocking sound is most likely the primary chain slapping around (won't really hurt it).

If you do not want to go through taking the carbs off yet, try this:

Fill your gas tank and leave room to add 8 oz of ATF. (Automatic transmission Fluid...any kind, doesn't matter...Oh...add the ATF at this point) Get the bike warmed up real good and ride for at least a good 50 miles at highway speed. On your way back to the house, run out 2nd gear real fast up to at laest 6500 RPM and let go of the throttle real fast and have the engine drag your speed down. Do this several times. What you are doing is taking a warmed engine that has a good cleaning agent in the gas and creating real high vacuum by running up the RPM and letting go of the throttle which sometimes will suck the jets clean if they are not clogged real bad.

Once it is able to settle, you have to sync the carbs again (preferably at idle). If that doesn't work....pull the rack and clean by hand.

plus one try that first

mcgovern61":2dx2eo5t said:

Yep, the idle jets are clogged. The knocking is from your engine being out of balance at idle (left to right) and the knocking sound is most likely the primary chain slapping around (won't really hurt it).

If you do not want to go through taking the carbs off yet, try this:

Fill your gas tank and leave room to add 8 oz of ATF. (Automatic transmission Fluid...any kind, doesn't matter...Oh...add the ATF at this point) Get the bike warmed up real good and ride for at least a good 50 miles at highway speed. On your way back to the house, run out 2nd gear real fast up to at laest 6500 RPM and let go of the throttle real fast and have the engine drag your speed down. Do this several times. What you are doing is taking a warmed engine that has a good cleaning agent in the gas and creating real high vacuum by running up the RPM and letting go of the throttle which sometimes will suck the jets clean if they are not clogged real bad.

Once it is able to settle, you have to sync the carbs again (preferably at idle). If that doesn't work....pull the rack and clean by hand.

Click to expand...

Finally another suggesting my method! I'd still run the Seafoam with the atf until it's finally clean. Then reset the air fuel mix screws and synch.

slabghost":vk3bz910 said:

mcgovern61":vk3bz910 said:

Yep, the idle jets are clogged. The knocking is from your engine being out of balance at idle (left to right) and the knocking sound is most likely the primary chain slapping around (won't really hurt it).

If you do not want to go through taking the carbs off yet, try this:

Fill your gas tank and leave room to add 8 oz of ATF. (Automatic transmission Fluid...any kind, doesn't matter...Oh...add the ATF at this point) Get the bike warmed up real good and ride for at least a good 50 miles at highway speed. On your way back to the house, run out 2nd gear real fast up to at laest 6500 RPM and let go of the throttle real fast and have the engine drag your speed down. Do this several times. What you are doing is taking a warmed engine that has a good cleaning agent in the gas and creating real high vacuum by running up the RPM and letting go of the throttle which sometimes will suck the jets clean if they are not clogged real bad.

Once it is able to settle, you have to sync the carbs again (preferably at idle). If that doesn't work....pull the rack and clean by hand.

Click to expand...

Finally another suggesting my method! I'd still run the Seafoam with the atf until it's finally clean. Then reset the air fuel mix screws and synch.

Click to expand...

Where do you think I got it from?? You suggested this several times in the past! :thanks:

How does the knocking go away? Does it go away when the carbs are in sync? My bike is doing the same thing with the irregular revs and knocking at low idle.

elevatorman71":3hnfyzqp said:

How does the knocking go away? Does it go away when the carbs are in sync? My bike is doing the same thing with the irregular revs and knocking at low idle.

Click to expand...

If the knock is from out of sync carbs it is because the gas is exploding at a slightly different rate causing an uneven load on the primary chain which then hits (flaps) up inside the case. Syncing the carbs (and having clean idle circuits) allows the cylinders to load and fire evenly (not the same as being out if time).

Ahhhh. I need a good sync job then. Giggity! Anyone in Cincinnati good with the mercury sticks?

I'm a good bit east of you sorry. I'm pretty sure though we have a couple guys close. Manometers (mercury stick) are pretty simple to use actually.

if i were to do them by myself what r the correct settings? rpm's? stuff like that.

elevatorman71":2buvlyy9 said:

if i were to do them by myself what r the correct settings? rpm's? stuff like that.

Click to expand...

Start off by watching these videos:

viewtopic.php?p=27985#p27985

viewtopic.php?p=31115#p31115

The 1980 and 1981 idle jets are pressed in the later models are easily retrieved by just unscrewing, I have read of guy's using a guitar string and such... First thing you should know is something about the jet itself, you know how the main jet looks with the holes on the sides, well that's what the idle jet looks like and it has a tiny hole straight down the center of the jet about 3/4" deep same with the side ones, guys think by poking that hole out of the center clean their good, not the case, see the jets I pulled on my 81 were clogged on the sides, after consulting with a long time Goldwing mechanic friend he instructed me to get a #2 easy out bit and a small adjustable wrench and turn the jet out until it snaps the seal and the jet comes out, some guy's use dry wall screws and wiggle and pull to get them out, you can try soaking them first perhaps it will work, you will never really know unless you physically see the holes clean, someone on another site tried the easyout and it broke on him, well that's because he used a #1 bit..gotta use a #2 ...Once you pull them and clean them with a very tiny wire, I used a small wire off a electrical wire, one of the stranes...But fiist I soaked them over night in carb cleaner, just lightly tap them back in place using the easyout bit and turn clockwise, and your bike will idle nicely, the float heights need to be measured proper too, do both of these things before you even think of syncing anything..and set your idle screws too asthese guys say to.. This is how I did mine, haven't had a problem since and yes mine sounded probably worse than yours...The main thing here is do as you find fit, if your not comfortable pulling them then don't..Read all you can on the subject.. It's scray I know....I fear nothing ha ha One lat thing, you do not want to damage these holes by using too large a wire, a wire brush wire will work but make sure it's a small wire brush..Good luck Check your vaccum advance too...Timing too...Well Guy's he asked ha ha :smilie_happy:

Geez, you guys are all such a big help. Well, I figured since its a few months until I can ride, why not pull the carbs. I did that on saturday. A little challenging but with the instructions I found on this site, I managed to do it without any real problems. Hardest part (of course) is the wiggling out. So, there out. Im gonna go after cleaning the idle jets. So, "littlebeaver" says, soak them in carb cleaner. by soaking them, you dont mean the whole thing right? Maybe thats a dumb question. I was just going to spray either carb cleaner or seafoam down into the idle jet, leave it sit (over night) and then use the wire brush bristle technique recommended. My question is relative to carb cleaner. do I need to be concerned with the carb cleaner damaging whatever rubber seals they come in contact with? I heard a few others mention this. Ok, im off now to buy a #2 (not #1) easyout. Thanks. Ill keep you posted.

yes big time ...i wouldnt even use the stuff on the jets unless i exhasted myself first with just using wire bristle...all the o rings could be damaged big time if allowed to get hit with it

I was saying to soak the idle jets once they have been removed in carb cleaner, it will loosen up the hard deposits in the tiny holes, you can also just use brake cleaner, it works really well.. Those jets are in there now, so when you start to turn them do it slowly and the seal should give..

Ok, the #2 easyout doesnt fit. To large. Im scared to try the #1.

Wow it doesn't, hummmm mine has a number #2 mark on it, you can use a drywall screwscrew it in the hole and wiggle and pry up or I can see if I can send you my bit if you want..Just send it back when your done..Send me your address on a pm...And I'll put some money in for the mistake on your bit...I have the bit in my hand, just say the word and I'll send it.. You know what you don't have to send it back just keep it, I'll send it priority mail for you..I'm sorry man...I am still thinking of making a video of this procedure...Ok here's what I will do for you, I will make a video tonight on how I remove these to show you how I do it using my easyout bit, ok, just be patient and wait for it, I'm going to the gargage to pull the carbs now,when the wife gets home she can hold the camera, I feel it's best to show you rather than just tell you..

Please forgive for making everyone wait for this video, it should have been made months ago...https://www.youtube.com/watch?v=REJCedXmQYw I'm sorry, Dan if you want to place it where it should be go for it... Mandorider I can send you my bit if you wish...No problem man..

Sure helps to see it done, thanks beav!

The vid will find a good home.