I ordered the Yamaha Raptor petcock and will switch it with the stock petcock next week when it comes in the mail.

2 questions:

1) Can I just seal the vacuum to the carburetor with some silicone sealant or do I need to actually cap it with a plug or a cap?

2) I saw in another forum post that someone took the metal/tube line from the stock (which had a longer Reserve line), unscrewed it or popped it off and then changed it over to the Yamaha Raptor tube (which had a shorter reserve line).  Has anyone done this and is this reliable?  It won't get loose or anything?

Thanks for any advice.

The rubber vacuum caps that I've bought at auto stores haven't lasted very long. If you go that route keep an eye on them. I finally put the hose from the original petcock back on the carb, stuck a 1"long machine screw in the open end, and tie wrapped the free end of the hose to the frame up under the tank.

There are better quality caps available, made of silicone, but you'll probably have to order them online.  I've never seen them at any of the chain auto stores around here.

My bike is a 2015, a holdover purchased summer 2018.  The bike has only 1700 miles on it now, sitting for most of it's life.  

The bike has been running rough lately so I had a mechanic buddy look at it and sure enough...faulty factory petcock.  Order put in to Ron Ayers for a Raptor 660.

Wished I had replaced it, as recommended by those on this site, at purchase.

Cam chain tensioner is the next order of business.  I won't be caught off guard on that one!