bad gas milage and missing plugs

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Can75

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Im looking for a little help with a '97 gettting around 16 mpg. I just got the bike so I don't know any history on it. the only aftermarket items i notice is the supertrapp exhaust. One of the coils was bad so i converted it to COP. Everything else seems to be stock. Each carb is missing a plug just to the left of the A/F screw. I rebuilt the carbs and ran it with out the plugs and also tried plugging to holes and it made no difference. It idles/runs the same plugged or not. when I pull the spark plugs I can see that 3 of the cylinders are running very rich. The A/F screws are all at 2.5 turns out. I've tried adjusting the A/F screws and on three of the carbs I can turn them all in and the bike doesn't even stumble. Thoughts?
 
Im looking for a little help with a '97 gettting around 16 mpg. I just got the bike so I don't know any history on it. the only aftermarket items i notice is the supertrapp exhaust. One of the coils was bad so i converted it to COP. Everything else seems to be stock. Each carb is missing a plug just to the left of the A/F screw. I rebuilt the carbs and ran it with out the plugs and also tried plugging to holes and it made no difference. It idles/runs the same plugged or not. when I pull the spark plugs I can see that 3 of the cylinders are running very rich. The A/F screws are all at 2.5 turns out. I've tried adjusting the A/F screws and on three of the carbs I can turn them all in and the bike doesn't even stumble. Thoughts?

Got a photo of these plugs?

How detailed was your rebuild?
 
In the rebuild I used the kit in the picture. I used a guide I found here on the forum to rebuild them. I pulled the carbs apart and soaked the carbs in a carb cleaner bath for about an hour. I sprayed carb cleaner though all the little holes I could find. Then I blew out all the holes with air and put the carbs back together using the rebuild kit. the unpluged holes are shown in the attached pic.
 

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And I just noticed said to the left when i meant to the right of the A/F screw. Oops!
 
In the rebuild I used the kit in the picture. I used a guide I found here on the forum to rebuild them. I pulled the carbs apart and soaked the carbs in a carb cleaner bath for about an hour. I sprayed carb cleaner though all the little holes I could find. Then I blew out all the holes with air and put the carbs back together using the rebuild kit. the unpluged holes are shown in the attached pic.

They should look like this-----:bang head:
 

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Im looking for a little help with a '97 gettting around 16 mpg. I just got the bike so I don't know any history on it. the only aftermarket items i notice is the supertrapp exhaust. One of the coils was bad so i converted it to COP. Everything else seems to be stock. Each carb is missing a plug just to the left of the A/F screw. I rebuilt the carbs and ran it with out the plugs and also tried plugging to holes and it made no difference. It idles/runs the same plugged or not. when I pull the spark plugs I can see that 3 of the cylinders are running very rich. The A/F screws are all at 2.5 turns out. I've tried adjusting the A/F screws and on three of the carbs I can turn them all in and the bike doesn't even stumble. Thoughts?

You can't run ONE cop as a replacement for a stock coil. I bought mine here----
http://www.ebay.com/itm/1985-2007-Y...ash=item2f08ac5c56:g:dwMAAOSwuAVWwqjT&vxp=mtr
 
Those are access holes for factory machining and are plugged with brass balls

I would assume its important to have those holes plugged, however, I have tried plugging them and the bike runs the same either way. So I would assume those holes are not my only problem. Is there maybe something I missed in the rebuild that would cause such bad gas mileage?
 
Those are access holes for factory machining and are plugged with brass balls

I would assume its important to have those holes plugged, however, I have tried plugging them and the bike runs the same either way. So I would assume those holes are not my only problem. Is there maybe something I missed in the rebuild that would cause such bad gas mileage?

That's a possibility, a complete rebuild is pretty detailed.
 
Float setting is critical. Also, the needle/seat has to seal, or hold back fuel pump pressure. It usually isn't an issue, but should be checked. I'd plug the holes to eliminate the possibility of a problem.
 
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