hi all.does letting these bikes idle too long fxxk the spark plugs.or is there something on these th

kebabs

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hi all .does idling these bikes too long fxxk the spark plugs ?or is there something on the bike that would cause the plug to fail quickly?advanced timing etc.thanks
 
I think as long as the carbs are tuned, you have a solid ignition and good compression, the bike should be able to idle all day long without too much itrouble other than not having adequate air flow over the cylinders in hot temps (i.e. probably not an issue in Scotland).
 
I think as long as the carbs are tuned, you have a solid ignition and good compression, the bike should be able to idle all day long without too much itrouble other than not having adequate air flow over the cylinders in hot temps (i.e. probably not an issue in Scotland).
thanks for your reply. having a larger pilot jet and main jet would this cause the plugs to foul quickly ?
 
having a larger pilot jet and main jet would this cause the plugs to foul quickly ?

It could. Also, having the idle mixture screws too far out can cause black fouling of the plugs. If you are trying to correct plug fouling, try and change only one thing at a time and then spend some time evaluating the result. Changing too much at once can have you chasing your tail.
 
It could. Also, having the idle mixture screws too far out can cause black fouling of the plugs. If you are trying to correct plug fouling, try and change only one thing at a time and then spend some time evaluating the result. Changing too much at once can have you chasing your tail.
thanks for your reply .I had been experimenting with a larger pilot and main jet and raisiing throttle needle one notch.bike did run but plugs were black and suity.ive returned the needle to its original position and jet sizes to where they were when I bought the bike .140 main jet and 42.5 piot .fuel screws are 3.5 turns out on each carb this set the fastest idle.carbs were also balanced using carb tune.once the fastest idle was set with the fuel screws I adjusted the idle to 1200rpm with the idle screw between the carbs .the bike also has pod filters.the plugs are not as suity now .was thinking should I go down further in jet sizes? to get it even leaner .
 
thanks for your reply .I had been experimenting with a larger pilot and main jet and raisiing throttle needle one notch.bike did run but plugs were black and suity.ive returned the needle to its original position and jet sizes to where they were when I bought the bike .140 main jet and 42.5 piot .fuel screws are 3.5 turns out on each carb this set the fastest idle.carbs were also balanced using carb tune.once the fastest idle was set with the fuel screws I adjusted the idle to 1200rpm with the idle screw between the carbs .the bike also has pod filters.the plugs are not as suity now .was thinking should I go down further in jet sizes? to get it even leaner .
I also had problems with the original petcock. but it now has been replaced.
 
ive returned the needle to its original position and jet sizes to where they were when I bought the bike .140 main jet and 42.5 piot .fuel screws are 3.5 turns out on each carb

I think that you are going in the right direction. Your bike probably had the following jet settings when stock:
Main jet 132.5
Pilot jet 42.5
Needle clip in 3rd slot from the top

So, your main jet is going to be perhaps too big as I would expect with pods you would need +1 (135), maybe +2 (137.5) larger on the main versus the stock jet. But, ride it for a good while, check the plug colors and go from there. If the plugs are still sooty after idling for a while, maybe turn down the pilot mixture screws to 3. as a first step.

Let us know how it goes.
 
I think that you are going in the right direction. Your bike probably had the following jet settings when stock:
Main jet 132.5
Pilot jet 42.5
Needle clip in 3rd slot from the top

So, your main jet is going to be perhaps too big as I would expect with pods you would need +1 (135), maybe +2 (137.5) larger on the main versus the stock jet. But, ride it for a good while, check the plug colors and go from there. If the plugs are still sooty after idling for a while, maybe turn down the pilot mixture screws to 3. as a first step.

Let us know how it goes.
thanks for your reply. when I got the bike I thought it was running way to rich just by the smell of the exhaust fumes and colour of tailpipe. the manual said 142.5 for main jet.previous owner had a 140 .I also thought with the pods you went up on the jet sizes si I put a 145 in and obviously made it worse but also thought is the carb I have different from the manual??.your spot on to by saying one change at a time ,I learned a lesson there.this is a project bike and second bike so not on it much and the weather here just now is crap.regarding the fuel mixture screws shouldn't they be set at the fastest idle .if I were to turn them bk half turn to 3 turns out the engine would start to die.when I get time I'll change the 140 jet to a 137.5.thanks so much for your advice and I'll let u know the outcome.carbs off again lol
 
thanks for your reply. when I got the bike I thought it was running way to rich just by the smell of the exhaust fumes and colour of tailpipe. the manual said 142.5 for main jet.previous owner had a 140 .I also thought with the pods you went up on the jet sizes si I put a 145 in and obviously made it worse but also thought is the carb I have different from the manual??.your spot on to by saying one change at a time ,I learned a lesson there.this is a project bike and second bike so not on it much and the weather here just now is crap.regarding the fuel mixture screws shouldn't they be set at the fastest idle .if I were to turn them bk half turn to 3 turns out the engine would start to die.when I get time I'll change the 140 jet to a 137.5.thanks so much for your advice and I'll let u know the outcome.carbs off again lol
another thing I would like to ask.i have pod filters on .I have ram air filters these are a lot bigger and made of foam would these increase the air intake and allow the carbs to run leaner??
 
I don't think the larger size pods should make much of a difference. They might increase the air flow some over a smaller pod filter, but not so much that you would have to go several sizes up on the jets by using them versus the smaller pods.
 
I don't think the larger size pods should make much of a difference. They might increase the air flow some over a smaller pod filter, but not so much that you would have to go several sizes up on the jets by using them versus the smaller pods.
I'm bk.lol.regarding the fuel screws I have them 3.5 turns out this sets the fastest idle.whem I turn the right fuel screw in 2 from 3.5 out the engine dies.on the left side if I turn it back in half a turn from 3.5 out the engine dies .why would there be a difference ?is one screw worn more than the other?
 
I am guessing that the differences in the screw settings between carbs might be from slight machining differences of the carb internals. The mixture screw settings on my carbs are slightly different, and when I measured the factory settings after removing the anti-tamper plugs that were installed, the mixture screws were also not the same. The main thing is to get them so the bike idles and runs correctly.
 
I am guessing that the differences in the screw settings between carbs might be from slight machining differences of the carb internals. The mixture screw settings on my carbs are slightly different, and when I measured the factory settings after removing the anti-tamper plugs that were installed, the mixture screws were also not the same. The main thing is to get them so the bike idles and runs correctly.
ok thanks for that.ill try going down a main jet size first .if it's still running rich I'll turn the fuel mixture screws in half a turn from 3.5.your info is much appreciated
 
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