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Carburetor cleaning / rebuild


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Thats black but mostly from a rich Long running condition in my opinion. OR .... bad valve seals/rings but that black of a piston would show a constant blueish smoke from the exhaust.  
If it were me i would get a can of the gum out carburetor cleaner and spray it in the head and let it sit over night. It will loosen up most of the garbage on the piston.  I have a carburetor cleaning kit and it comes with small brushes that you can bend and stick inside the spark plug hole and do a little scrubbing on the piston It helps. When your ready crank the engine without the spark plug and blow it all out of the head.  Super important is to make sure the kill switch is off while cranking and if it wont crank with the kill switch then put a rubber glove over the spark plug wire boot and make sure it does not spark against anything! 

Re inspect and see how it looks. If most of it goes away then the rest will burn off once its dialed in right.  
I would change the oil as well because the gum out can slip by the rings and get into the oil.   

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I already have all the oil out which smelled like straight gas saw there wasnt a washer on the oil plug. id have to say this guy ran it rich for like 1 year without even touching the oil. So much dirt had to clean off first power wash didnt get everything so had to spraynine almost the whole bike and than power wash again now im gonna have to do it again. Because it still didnt get everything.. For an aircooled bike to be that dirty just makes me sad... Guy that had it before me obviously didnt take that much care of it, And yeah this design of bike wont crank with the kill switch on because it actually just cuts the whole power system. I was thinking of doing what your saying but also running a can of seafoam through

Edited by pablo Blake
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15 hours ago, Frank Angerano said:

Thats black but mostly from a rich Long running condition in my opinion. OR .... bad valve seals/rings but that black of a piston would show a constant blueish smoke from the exhaust.  
If it were me i would get a can of the gum out carburetor cleaner and spray it in the head and let it sit over night. It will loosen up most of the garbage on the piston.  I have a carburetor cleaning kit and it comes with small brushes that you can bend and stick inside the spark plug hole and do a little scrubbing on the piston It helps. When your ready crank the engine without the spark plug and blow it all out of the head.  Super important is to make sure the kill switch is off while cranking and if it wont crank with the kill switch then put a rubber glove over the spark plug wire boot and make sure it does not spark against anything! 

Re inspect and see how it looks. If most of it goes away then the rest will burn off once its dialed in right.  
I would change the oil as well because the gum out can slip by the rings and get into the oil.   

Hey frank thanks for info!!!! Any change we can get you to do a post  on DVA tester for pulser coils etc? 

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@pablo Blake sorry I didn't see that post about the screw.  So that is your air/fuel screw obviously.   You will see a lot of  threads down there so don't think its buried all the way. 
Before you touch it what i always do is tighten it to a SNUG position and count the amount of turns that it takes before its snug. Should be in the two maybe two and a half turns in range.  Write that down because you will want to set it back at that position later on after the carburetor is cleaned out.   
Adjusting that screw while the engine is running is quite challenging and takes a custom mini screwdriver and some small hands and patience.  There is a method to it as well by listening to the engine run. 

The manual also tells you how many turns to set the screw at and it should be in the same area of where you found it. 

202D947C-2784-4C82-B69D-ED133C805D77.jpeg

Edited by Frank Angerano
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@Jacob Dellinger there really isn't much to a pulsar/trigger coil to do a write up, i guess the tester would be a good idea explaining some ohm readings and the differences between the settings. I will see what i can put together.  
In the meantime if you are having a problem or need some direction/explanation  im sure we can help you along brother.    

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Hi Frank Great info.  I would like to add, if one needs to check float adjustments, find it in your service manual or Google it. The best way I've found is with the carb upside down, is to use a Harbor Freight digital Caliper, using the end stick, that protrudes out the handle, for the best and accurate measurement.  This makes an easy way to set the float level than using a ruler, or the paper gauges, that sometimes are sent with a kit.  I used this for my Mikuni Carbs on 2 1988 Yamaha TerraPro's.  Very Accurate.

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