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Advise
allankelly1:
I presume adjusting mixture screws can muck up your carb sync slightly?
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K2-K6:
--- Quote from: allankelly1 on July 21, 2021, 06:57:30 PM ---I presume adjusting mixture screws can muck up your carb sync slightly?
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--- End quote ---
No it won't affect carb sync at all. There's so many myths about on t'internet that are mostly wrong and lead people to do things which are incorrect.
Carb sync is parity of the throttle slides to give equal air volume to each cylinder, although it affects idle smoothness when maladjusted it's not the final setting of idle smoothness. Once the balance of synchronisation is set that's ok for all engine speeds and remains in parity if the adjustment is properly secured.
The idle air circuits then trim the fuel demand at very small level to bring parity of combustion for each of the cylinders, in effect the "icing on the cake" of tickover refinement. Moving these screws has no impact on throttle slide sync.
In addition, the idle jet size sets it's ultimate flow which is tempered by the air screw adjustment. Going in or out with the screw doesn't change the final full flow of the idle circuit but alters the angle of the slope leading to that final full flow. So you can play with the airscrew with no other detrimental effect, just remember where you've set them , try it out and go again with another adjustment to see the affect as Julie indicates above.
Airscrew out further = weaker to lighten the plug, with of course the opposite if you needed rich.
What plug gap are you running?
Nurse Julie:
--- Quote from: allankelly1 on July 21, 2021, 06:57:30 PM ---I presume adjusting mixture screws can muck up your carb sync slightly?
Sent from my iPhone using Tapatalk
--- End quote ---
No, it doesn't affect the sync. 2¼ turns is a long way out to be showing soot like that 🤔 What position are the needles in and do you have standard size jets fitted? You're not running pods I take it? Edit... No, I can see the plenum chamber now I've put me specs on 🙄🙄🙄
allankelly1:
--- Quote from: K2-K6 on July 21, 2021, 07:21:18 PM ---
--- Quote from: allankelly1 on July 21, 2021, 06:57:30 PM ---I presume adjusting mixture screws can muck up your carb sync slightly?
Sent from my iPhone using Tapatalk
--- End quote ---
No it won't affect carb sync at all. There's so many myths about on t'internet that are mostly wrong and lead people to do things which are incorrect.
Carb sync is parity of the throttle slides to give equal air volume to each cylinder, although it affects idle smoothness when maladjusted it's not the final setting of idle smoothness. Once the balance of synchronisation is set that's ok for all engine speeds and remains in parity if the adjustment is properly secured.
The idle air circuits then trim the fuel demand at very small level to bring parity of combustion for each of the cylinders, in effect the "icing on the cake" of tickover refinement. Moving these screws has no impact on throttle slide sync.
In addition, the idle jet size sets it's ultimate flow which is tempered by the air screw adjustment. Going in or out with the screw doesn't change the final full flow of the idle circuit but alters the angle of the slope leading to that final full flow. So you can play with the airscrew with no other detrimental effect, just remember where you've set them , try it out and go again with another adjustment to see the affect as Julie indicates above.
Airscrew out further = weaker to lighten the plug, with of course the opposite if you needed rich.
What plug gap are you running?
--- End quote ---
Hi
Plug gap is the Haynes manual 0.7 to 0.8mm
Best wishes Al
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allankelly1:
--- Quote from: Nurse Julie on July 21, 2021, 07:22:30 PM ---
--- Quote from: allankelly1 on July 21, 2021, 06:57:30 PM ---I presume adjusting mixture screws can muck up your carb sync slightly?
Sent from my iPhone using Tapatalk
--- End quote ---
No, it doesn't affect the sync. 2¼ turns is a long way out to be showing soot like that What position are the needles in and do you have standard size jets fitted? You're not running pods I take it? Edit... No, I can see the plenum chamber now I've put me specs on
--- End quote ---
Every thing is standard other than exhaust
When I was rebuilding the carbs jetting was standard but they are the original jets and correct to the Haynes manual 40 pilots and 75 mains so I have no idea if they have been attacked with a piece of wire in the past judging by the rest of the bike when I got it
As for needles not sure what clip position they are’s in
Haynes manual is not very clear on how the slides disassemble so any advise on how to take out and check they are in third groove? should be most helpful as I guess maybe I need to drop the needles one groove maybe?
Also before the rebuild plugs were very sooty and the current plug is much better
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