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Prolong the Life of Those Vinyl Carb Fittings!

Hereís a how to article on how to make a set of heat isolating gaskets to install between the head and the vinyl compliance fitting that the carburetor fits into. These are quickly heat damaged in serviced, I personally get tired of people complaining about them. So Iíve solved it for you! Get them out of direct contact with the hot cylinder head and youíll greatly prolong their service life! This is also a great way to make heat isolating intake gaskets for your Russian made carbs if you run an older bike. I recommend 1/8" total thickness to protect the vinyl compliance fittings and a 3/16" thickness to protect a carb from overheating. If you use 3/16" thickness to protect your compliance fitting, you may have to get longer fasteners to attach the fitting. Stock ones are fine for a 1/8" thickness.

These gaskets are easy to make. No complicated shop tools needed.

These are made from rubberized asbestos gasket sheeting made by the Garloc Company. Itís about $7 per square foot where I buy mine at a local hydraulic service company. This is 1/16" sheet. You can get it thicker, but it becomes much more difficult to cut cleanly.

Step-1: Make a pattern:

Remove your carbs and compliance fittings. Get a piece of brown paper like from a grocery bag. Lay the paper on the hole for the intake on the head. Then rub it with the edge of a wrench or something similar. Donít let the paper move around. You want to make a rubbing to use as a pattern for the gasket. Once you have a neat rubbing, cut it out with scissors and a #11 X-Acto blade. Small hole punches can be used too. These are available cheap at harbor Freight. NOTE! On the outside circumference of the pattern, cut it out leaving an extra 1/8" of material around the outside edge. This will strengthen the gasket and the extra material will not get in the way of anything.

Step-2: Trace pattern onto gasket sheeting:

Lay the pattern on the sheeting and trace around it with a permanent marker. See photo. I like to trace mine lengthways with the grain of the gasket sheet.

Step-3: Cut holes:

IMPORTANT! Cut the holes out BEFORE cutting the individual gaskets out to prevent them from splitting. The material has a plastic quality to it and will deform as you punch holes. Do the holes first. I like to punch the small holes first and then I punch out the large ones. If you donít have a large hole punch like I use, just use your #11 X-Acto blade and make multiple light cuts around the circle until you have cut the center free of the sheet. If you punch the holes, youíll notice it deforms the material in the direction it was punched. Just gently tap it back flat with a mallet.

Step-4: Cut out the individual gaskets:

Using a heavy pair of shears, cut away the individual gaskets leaving about 1/8 to ľ" around where you will make the final cutting. Remember this stuff can deform. Doing it this way and THEN making a final cutting will prevent deforming the gasket material. Now make your final scissors cut to complete the set of gaskets. I made four each 1/16" thick. So I can bond a pair together to get the final 1/8" thickness I need.

Step-5: Bond them together to get the final thickness needed:

You can see in the photo I use old fashioned "Gasketcinch" adhesive. It dries to a tack quickly and works well. But silicone RTV could be used too. Be sure not to use too much as the RTV will squish out. Using the applicator, apply a light coat to the surfaces to be bonded. I also applied a light coating to the back side of the compliance fitting to stick it well to the gasket. None is need where it seals to the head. The Garloc will form a good seal on it own. Remember? Itís deforms easily. It will mate to the imperfections and form a good seal.

 

 

Step-6: Re-Install on bike:

Reinstall the compliance fittings & gaskets on the head. I use blue Loctite on all fasteners. See the final photo to see how it looks. I recommend synchíing the carbs after any maintenance like this. Have fun!

 

Rich Maund

 

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