Misfire after sitting a few months-not fixed...
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Re: Misfire after sitting a few months-looking for suggestio
Hi jamesp.
To know which jet is in play, I notched my throttle grip and marked the cable pull housing to actually know the slide opening when riding/tuning. I am sure that my bike is not idling at 3500 rpm regardless of engine load. Clean 'em again anyway, to be sure, to be sure.
Hi jamesp.
To know which jet is in play, I notched my throttle grip and marked the cable pull housing to actually know the slide opening when riding/tuning. I am sure that my bike is not idling at 3500 rpm regardless of engine load. Clean 'em again anyway, to be sure, to be sure.
Re: Misfire after sitting a few months-looking for suggestio
Corrosion loves to grow when a bike sits. Make sure to clean all your grounds & kill switch contacts. Things also shrink so check for air leaks at the carbs. Maybe check valve adjustments too. Ultrasonic cleaners are cool but don't leave stuff to long. I saw a pair of Amals that were destroyed by some twit who left them in one for too long, he wouldn't say how long but I got the impression it was more than two days so his bad.
Corrosion loves to grow when a bike sits. Make sure to clean all your grounds & kill switch contacts. Things also shrink so check for air leaks at the carbs. Maybe check valve adjustments too. Ultrasonic cleaners are cool but don't leave stuff to long. I saw a pair of Amals that were destroyed by some twit who left them in one for too long, he wouldn't say how long but I got the impression it was more than two days so his bad.
Re: Misfire after sitting a few months-looking for suggestio
Re ultrasonic cleaning - the default on my machine is 3 minutes. I assume that's set for jewellery which is what many people buy them for but when I clean my carbs I find that 3 five minute blasts is plenty. Use water with a touch of washiung up liquid. Also it's best to clean any crud off the outside first so you don't circulate it, and change the water between blasts.
I've never heard of it damaging things but I guess anything can be abused -it's not a substitute for shot blasting! My understanding is that microbubbles are agitated against the surfaces at very high frequency and being so small they get everywhere inside. I think of it as being somewhat similar to the action of a microwave cooker but cleaning instead of heating.
Re ultrasonic cleaning - the default on my machine is 3 minutes. I assume that's set for jewellery which is what many people buy them for but when I clean my carbs I find that 3 five minute blasts is plenty. Use water with a touch of washiung up liquid. Also it's best to clean any crud off the outside first so you don't circulate it, and change the water between blasts.
I've never heard of it damaging things but I guess anything can be abused -it's not a substitute for shot blasting! My understanding is that microbubbles are agitated against the surfaces at very high frequency and being so small they get everywhere inside. I think of it as being somewhat similar to the action of a microwave cooker but cleaning instead of heating.
Re: Misfire after sitting a few months-looking for suggestio
i would look at the pilot circuit
Modern unleaded fuels leave a varnish like residue in the pilot circuit when stood , hence why Amal chose to make the premier carb with removable pilot jets
don`t forget the old pilot bush / 25 jet only has a 16 thou hole to block any dirt particles or gum will cause havoc with low speed running
if it runs OK over 3000 RPM it suggests blocked pilots , do the basics before spending time looking for expensive electrical faults
i would look at the pilot circuit
Modern unleaded fuels leave a varnish like residue in the pilot circuit when stood , hence why Amal chose to make the premier carb with removable pilot jets
don`t forget the old pilot bush / 25 jet only has a 16 thou hole to block any dirt particles or gum will cause havoc with low speed running
if it runs OK over 3000 RPM it suggests blocked pilots , do the basics before spending time looking for expensive electrical faults
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Re: Misfire after sitting a few months-looking for suggestio
Ah duh modern lean burn fuels do not leave nearly as much varnish as gasoling served in the 70's. What clogs the pilot is same whitish stuff seen on coaches noses and bottom of fuel bowls, Zine Oxide so no organic solvent will touch it only physically poking out or dissolving in weak acid like acetic boil or stronger base like lye - for a short time.
Ah duh modern lean burn fuels do not leave nearly as much varnish as gasoling served in the 70's. What clogs the pilot is same whitish stuff seen on coaches noses and bottom of fuel bowls, Zine Oxide so no organic solvent will touch it only physically poking out or dissolving in weak acid like acetic boil or stronger base like lye - for a short time.
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Re: Misfire after sitting a few months-looking for suggestio
What? I thought it was a cockroach! and how did he get into an Amal carby? Strong acid will get rid of him!Biscuit said:
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Re: Misfire after sitting a few months-looking for suggestio
I haven't seen any mention here if fitting new spark plugs. Best to fit new plugs and try again if you have not done so. I got fooled just recently with what looked like good spark plugs.
Dereck
I haven't seen any mention here if fitting new spark plugs. Best to fit new plugs and try again if you have not done so. I got fooled just recently with what looked like good spark plugs.
Dereck
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Re: Misfire after sitting a few months-looking for suggestio
Hi Dereck.
My first thought but he clearly states in the original post '...changed plugs several times,...'.
I will admit that I assumed, and still do, that he meant for different plugs!
kerinorton said:
Hi Dereck.
My first thought but he clearly states in the original post '...changed plugs several times,...'.
I will admit that I assumed, and still do, that he meant for different plugs!
jamesp
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Re: Misfire after sitting a few months-looking for suggestio
Just went through the float settings and rechecked the timing. No difference in running, except it seemed a bit cleaner. Regarding the many suggestions to check the idle circuits, can air be blown through with bowls on, or should I remove them first? May be a dumb question? One thing I wish I had done is drill them through and fit the opening with a set screw when I had them sleeved. Seems like a good idea. Thanks for all your suggestions.
Just went through the float settings and rechecked the timing. No difference in running, except it seemed a bit cleaner. Regarding the many suggestions to check the idle circuits, can air be blown through with bowls on, or should I remove them first? May be a dumb question? One thing I wish I had done is drill them through and fit the opening with a set screw when I had them sleeved. Seems like a good idea. Thanks for all your suggestions.
Re: Misfire after sitting a few months-looking for suggestio
Did you try tickling the floats while doing this. ?
This will tell you, instantly, if leaness is the problem, because tickling the floats should take away this condition.
And if the running suddenly becomes flawless, even if only temporary, tells you exactly where the problemo is.
(So would pulling on a bit of choke, but if you don't have a choke system fitted....).
jamesp said:
Did you try tickling the floats while doing this. ?
This will tell you, instantly, if leaness is the problem, because tickling the floats should take away this condition.
And if the running suddenly becomes flawless, even if only temporary, tells you exactly where the problemo is.
(So would pulling on a bit of choke, but if you don't have a choke system fitted....).
Re: Misfire after sitting a few months-looking for suggestio
You can blow air through all passages with the bowls still installed IF all passages are free and clear. And doing this may dislodge a small speck.
But to positively prove the passages are clear you need to remove the carbs. Here's how I do it. Holding the body in your hand (no need to remove jets) you will see (1) at the intake end a 5mm hole in the center, a blanked off hole to one side and a 3 1/2mm hole to the other side. (2) Looking at the bottom of from the floatbowl side you will see a tapped hole approx. diagonally across from the tickler. (3) Looking down into the carb through the slide bore, towards the flange side you will see two tiny holes, one on the inside, and one on the outside of the slide seat. (4) Take out the pilot air mix screw and....using the fluid of your choice, (carb spray, WD40, brakeclean, etc) fill the air screw hole and chase it with a shot of air. Fluid should come out of all the aforementioned orifices except for the central 5mm one at the intake. It will just kind of bubble out of the tapped hole on the float bowl side. It will flow pretty well from the hole at the intake side. And two nice little twin streams should piss out from the slide side.
You can blow air through all passages with the bowls still installed IF all passages are free and clear. And doing this may dislodge a small speck.
But to positively prove the passages are clear you need to remove the carbs. Here's how I do it. Holding the body in your hand (no need to remove jets) you will see (1) at the intake end a 5mm hole in the center, a blanked off hole to one side and a 3 1/2mm hole to the other side. (2) Looking at the bottom of from the floatbowl side you will see a tapped hole approx. diagonally across from the tickler. (3) Looking down into the carb through the slide bore, towards the flange side you will see two tiny holes, one on the inside, and one on the outside of the slide seat. (4) Take out the pilot air mix screw and....using the fluid of your choice, (carb spray, WD40, brakeclean, etc) fill the air screw hole and chase it with a shot of air. Fluid should come out of all the aforementioned orifices except for the central 5mm one at the intake. It will just kind of bubble out of the tapped hole on the float bowl side. It will flow pretty well from the hole at the intake side. And two nice little twin streams should piss out from the slide side.
jamesp
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Re: Misfire after sitting a few months-looking for suggestio
Today I checked the voltage at the Trispark with swich on, had app. 12.5 volts. I then took out the idle air screws, shot in WD40, then blew them out with compressed air. This seemed to help. I then did the same procedure using Seafoam. Not sure that was any better than the WD40, but I noticed it was running better above about a quarter throttle when I revved the throttle. I tried ticklers while running, no change. From closed up to a quarter throttle, motor is running uneven, wants to stall where it should be idling, some black smoke going out both exhaust, more so on the right a bit. I pulled the plugs, and they are black,sooty. Put in some cleaner plugs, still the same.
I also checked the timing, it seems to be correct @ 3500 RPM fully advanced. Any suggestions? Thanks.
Today I checked the voltage at the Trispark with swich on, had app. 12.5 volts. I then took out the idle air screws, shot in WD40, then blew them out with compressed air. This seemed to help. I then did the same procedure using Seafoam. Not sure that was any better than the WD40, but I noticed it was running better above about a quarter throttle when I revved the throttle. I tried ticklers while running, no change. From closed up to a quarter throttle, motor is running uneven, wants to stall where it should be idling, some black smoke going out both exhaust, more so on the right a bit. I pulled the plugs, and they are black,sooty. Put in some cleaner plugs, still the same.
I also checked the timing, it seems to be correct @ 3500 RPM fully advanced. Any suggestions? Thanks.
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Re: Misfire after sitting a few months-looking for suggestio
Hello Jamesp,
You have not said if you mechanically cleaned the idle jets. A #78 drill used by hand and carby cleaner is the best. WD40 and compressed air will not clean the jets if corroded.
Cheers
jamesp said:
Hello Jamesp,
You have not said if you mechanically cleaned the idle jets. A #78 drill used by hand and carby cleaner is the best. WD40 and compressed air will not clean the jets if corroded.
Cheers
Re: Misfire after sitting a few months-looking for suggestio
Tinsey, tiny, .016. The diameter of the B-string in a set of light guitar strings. This is what I use but you can also use a single wire from a wire brush. It may actually be a bit finer, or a single copper strand of copper wire from automotive wiring. Problem with that is not very stiff and easy to bend as you fiddle it all the way through the pilot jet.
jamesp said:
Tinsey, tiny, .016. The diameter of the B-string in a set of light guitar strings. This is what I use but you can also use a single wire from a wire brush. It may actually be a bit finer, or a single copper strand of copper wire from automotive wiring. Problem with that is not very stiff and easy to bend as you fiddle it all the way through the pilot jet.
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