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98” big bore plug chops always lean

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  #41  
Old 08-24-2022, 05:10 PM
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I ran it around town quick and then pulled the air cleaner off. No fuel coming out of the main jet needle hole. Plugged the hole on the bottom and to the rear of carb. It stalled. I did not see no 10 o clock hole.
 
  #42  
Old 08-24-2022, 06:13 PM
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Not sure what you meant by 10 o'clock hole. Look at the bottom of the throat. Here's a picture of a different carb, but shows the progression holes:


 
  #43  
Old 08-25-2022, 08:13 AM
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Originally Posted by WS6_Keith
Not sure what you meant by 10 o'clock hole. Look at the bottom of the throat. Here's a picture of a different carb, but shows the progression holes:

sorry I got that 10 o clock hole from another post I was reading. I did plug the hole on the bottom of the carb to the left and it did stall. Also not pulling any fuel from the main jet. I’m just stuck on why my fuel mixture won’t react with any pilot jet from a 46-50. It smells rich. Maybe because I have a 195 main? I was gonna tackle getting the main tuned in after I figured out the pilot.
 
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Old 08-25-2022, 08:49 AM
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The main jet has nothing to do with idle. You could remove the main jet and it should still idle on the pilot circuit without issue. Get the pilot/idle fixed first. The stock jet was a 42 right? Most times, bikes will idle just fine stock, so not a big reason to change it. Some people bandaid exhaust leaks which cause decel popping by richening up the idle circuit, but it shouldn't be necessary. A 45 is a common change, but it just means less turns on the mixture screw to achieve the same idle air/fuel ratio. With a 42 it should be about 3 turns out. 45, even less. The fact that this is a big bore engine would require LESS turns and possibly a smaller jet because your larger engine is sucking harder on the same size jet, which means there is better signal and more pull on the fuel through the jet. Given that you make mixture screw changes that don't seem to do anything, I'd go back to a 45 or maybe the 42 and see how responsive the bike is to the screw.
 
  #45  
Old 08-25-2022, 03:38 PM
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Remove the low speed needle, check for a crunched up "O" ring in the passage.

Make sure it is bottom to top of needle spring, washer, "O" ring.

Make sure the enricher(choke) is clean and seating in the carb.
 
  #46  
Old 08-25-2022, 08:14 PM
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Originally Posted by WS6_Keith
The main jet has nothing to do with idle. You could remove the main jet and it should still idle on the pilot circuit without issue. Get the pilot/idle fixed first. The stock jet was a 42 right? Most times, bikes will idle just fine stock, so not a big reason to change it. Some people bandaid exhaust leaks which cause decel popping by richening up the idle circuit, but it shouldn't be necessary. A 45 is a common change, but it just means less turns on the mixture screw to achieve the same idle air/fuel ratio. With a 42 it should be about 3 turns out. 45, even less. The fact that this is a big bore engine would require LESS turns and possibly a smaller jet because your larger engine is sucking harder on the same size jet, which means there is better signal and more pull on the fuel through the jet. Given that you make mixture screw changes that don't seem to do anything, I'd go back to a 45 or maybe the 42 and see how responsive the bike is to the screw.
I know the main jet has nothing to do with the idle. I was just mentioning maybe that’s why it smells rich and not because of the pilot. I will go back to a 45, but I just have a hard time believing the engine would only want a 45 with it having what is done to it now.

Originally Posted by Kabear
Remove the low speed needle, check for a crunched up "O" ring in the passage.

Make sure it is bottom to top of needle spring, washer, "O" ring.

Make sure the enricher(choke) is clean and seating in the carb.
I replaced the mixture screw and components with a ez screw
 
  #47  
Old 08-26-2022, 10:21 AM
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That ez screw could be your problem, it didn't work on my bike, the taper on the screw is different for different year carbs. Now it did work perfectly on my wife's bike and is still in use today.

But, I have her bike tuned a little rich so that it is easy to start.
 
  #48  
Old 08-26-2022, 12:03 PM
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Originally Posted by Kabear
That ez screw could be your problem, it didn't work on my bike, the taper on the screw is different for different year carbs. Now it did work perfectly on my wife's bike and is still in use today.

But, I have her bike tuned a little rich so that it is easy to start.
I will try to old one and see if it makes a difference. Thank you
 
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