The slides are vibrating rapidly as in up and down motion. When i twist the throttle the slided move as they should but the carbs are spitting fuel and popping. Anywhere near 2k and it hesitates and dies. Im waiting for a new rebuild kit for the carbs but it just dont add up. I made sure they were squeeky clean before i put them on so the jets cant be blocked
Here we go "AGAIN"
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comperssion is good so im thinking air myself. I was thinking about it last night and the only thing that was different with the carbs was when i was cleaning them the 2 tiny o rings that are at the base of the air/fuel mixture screw came out. Im just wondering if they somehow managed to twist a bit going back in. Slightly blockinging the air/fuel ratio
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Again, the slides move up and down in sync with the intake stroke of the cylinder that carb supplies. this is normal. more throttle will cause them to open more on each stroke.
you may have an issue with the carbs still, I am just pointing out the pulsing of the slides is normal.
if they didnt pulse, I would look at the slides, diaphrams, or other vacuum issue in the carb
you may have an issue with the carbs still, I am just pointing out the pulsing of the slides is normal.
if they didnt pulse, I would look at the slides, diaphrams, or other vacuum issue in the carb
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I don't think the air adjustment is going to cause all those symptoms so far above idle rpm.
By air test, I meant similar to a leakdown test, pressurizing the cylinder and see if there's any air where it shouldn't be, as with a leaking intake valve.
Won't hurt to check those o-rings, an internal air leak can only cause a problem. We could be looking at overlapping symptoms.
When does the popping occur? All the time, only above 2000 rpm, or only right before it dies? Or is it random?
By air test, I meant similar to a leakdown test, pressurizing the cylinder and see if there's any air where it shouldn't be, as with a leaking intake valve.
Won't hurt to check those o-rings, an internal air leak can only cause a problem. We could be looking at overlapping symptoms.
When does the popping occur? All the time, only above 2000 rpm, or only right before it dies? Or is it random?
It happens all the time. I cant touch the throttle or it will bog and instantly die. Right so here is what im doing. Iv ordered a fuel tap rebuild kit, carb rebuild kit. Im putting back on the surge tank and stock air filters. Leaving the emmisions crap off. Its deffo a carb problem because after the engine rebuild it would not fire as you no and once i cleaned the carbs it started first pick only now there is the current problem. I just pulled the jet cover and on the front carb the little triangular shaped rubber gasket was broke. Still together but just sliced if you get me. Could this have caused the problem. Also thanks mishiganteddybear. I get what you mean about the slides.
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Ok, I recall which bike this is, but often forget which member's bike has what done to it.
So it's sitting there idling and popping back through carb, then carries on and dies when you gas it more than 2000r,?
Petcock leaking doesn't help. Not sure I would put the airbox back in just yet. You haven't really cruised with the earshave yet have you?
The carb gasket probably isn't the problem but needs fixed.
If the answer to my first question is yes, I really think you're looking at a leaking intake valve and your carbs may be fine other than the gasket.
Also thinking an intake valve leaking might induce a bad pulse on the slides. I know they move, but you may have been seeing this pulse in the vacuum from the intake leak.
A vacuum gauge would show a consistent fluctuation downward every time that cylinder completes a cycle, with a leaking valve. An abnormal pulse in the vacuum. Great diagnostic tool to keep around, saves time and aggravation.
Spockster thank you for all your input. Iv just ordered a gauge so should be here hopefully by the end of the week. Have some bits ordered so all will get done regardless. Just hope that i dont got to pull the engine again for a valve job. I will keep this thread posted for future references.
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You're welcome, hope I'm not sending you on a wild goose chase. The answer to that question earlier was yes, correct ?
Pulled my engine twice in two days because I goofed installing the damper gear. I really wanted that first ride.
Second time was easier, quicker.
Where did you find the gauge? Was about to remove the one from the dash of my pickup, all my toolbox gauges are too old to use.
Look up some charts online for vacuum readings, will help with troubleshooting other engines. Though I've seen one or two that didn't jibe with printed manuals. Almost all Chilton, Haynes, Clymer automotive manuals have the chart in the troubleshooting section.
One of the vac gauge's best uses is checking for valve problems ... Oh and clogged Cats too.
Pulled my engine twice in two days because I goofed installing the damper gear. I really wanted that first ride.
Second time was easier, quicker.
Where did you find the gauge? Was about to remove the one from the dash of my pickup, all my toolbox gauges are too old to use.
Look up some charts online for vacuum readings, will help with troubleshooting other engines. Though I've seen one or two that didn't jibe with printed manuals. Almost all Chilton, Haynes, Clymer automotive manuals have the chart in the troubleshooting section.
One of the vac gauge's best uses is checking for valve problems ... Oh and clogged Cats too.
yes to the question earlier. Iv order one from motorcycle shop here in ireland so it should be right. I have the haynes manual so i will have a look in it for the specs. Iv pulled this engine more times than id like to say. Put it this way. 15 mins for an engine pull and 5 mins for carbs. Im sure i could take the engine apart at this stage witj my eyes closed lol. I think this time tho if it is the valves of something like that im just gonna send her to a mechanic and get it back when its ready to ride. I no it runs so thats the main thing. If it didnt run i would have just parted it out. Time will tell. Lets hope its an easy fix like something i over looked.🤞. On the other hand once i find the problem it should help anyone else that runs into this situation.
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Pretty good time for an engine pull!
You could verify the valve is leaking with an air pressure test. Need compressed air and a fitting that will thread into a spark plug hole.
You put air pressure into a cylinder, rotate crank to where all valves are closed, TDC of compression stroke, then listen for air escaping intake or exhaust.
Once the head is removed, you can fill the areas behind each valve with liquid to see if it leaks into the combustion chamber over time. Liquid like gasoline, alcohol, or probably even water.
You could verify the valve is leaking with an air pressure test. Need compressed air and a fitting that will thread into a spark plug hole.
You put air pressure into a cylinder, rotate crank to where all valves are closed, TDC of compression stroke, then listen for air escaping intake or exhaust.
Once the head is removed, you can fill the areas behind each valve with liquid to see if it leaks into the combustion chamber over time. Liquid like gasoline, alcohol, or probably even water.
yeh i seen some videos on valve leak test with fuel. The head was off the bike tho. Not sure if it could be done on the bike. Altho im sure if you could see the valve ports you might have some hope. Pretty neat idea with the air test. I might give that ago while i am waiting for my gauge to come
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Just make sure the threads are correct on your air fitting, don't want stripped plug holes.
A couple of times, I've made a fitting with an old spark plug, but it's a compromise. Can end up too leaky.
Problem found. This is definatly one for the record books. Ok so pulled the carbs again to take a look. Pulled the jets from both sides and low and behold the main jets are screwed. I obviously seriously over tightened them. In my defence.. ok i dont have any im an idiot lol. Judge for yourself by the pics. I await your roasting 😂
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While that's not good, I'm struggling to figure out how that would cause constant popping from one carb. A lean sneeze if fuel doesn't flow well, but only when the throttle is opened and just one pop.
Might check to see if the carb body is cracked near the jet holes.
Don't be too hard on yourself, this is one of ways we can learn.
At the bottom of the tube it bottomed out against the fuel passage way. Fuel flow was definatly restricted. Im prusuming this is why it wouldnt rev passed 2k. Most of the little holes in the tubes are bent shut. My thinking is limited fuel causing no fire of the front cylinder. Eventualy the vapor from the limited fuel gets built up in the exhaust and eventualy igniting causing popping sound. Thats my thinking of it. I tried to take as clear as pic as possibal.
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Just have to source them now pretty hard from ireland without having to wait weeks. Still waiting on a load of parts. So i will keep this updated as i go
yes stock jets and the carb rebuild kit i ordered dont have them in it. Typical. 62 euro from the netherlands for the 2 of them. 😲. I might check for harley ones. Might be easier to get. Is there a specific model i should search?
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