I noticed while removing fuel line from carburetor that petcock is not sealing off fuel completely when in off position. Just a drip, drip like a worn sink washer.I run carbs on my bikes dry after I ride them so I was going to order a rubber and gasket for the petcock.i noticed this is not the OE petcock on this bike so I was wondering whether the original Yamaha round rubber and gasket would fit this before I ordered them.I am uploading a picture to see if anybody might recognize this one.

Well I tried to post picture.
Would not load it.

I don't know but I kind of doubt if the OEM gaskets would fit in aftermarket petcock. I ordered a aftermarket one that was very cheap, and it didn't just drip when it was turned off, it actually poured out. I ended up ordering one for Yamaha Big Bear, and it turns off fine, but it only has a quarter inch output nipple, where your bike probably needs 5/16". I was able to adapt it, because I also have an inline filter on my CT1, but if you can afford it, I would try to get a OEM petcock. Being able to turn off the gas tank is pretty important.

Good advice, thanks Tom

There's a whole thread here on "modern" Yamaha petcocks that fit the old bikes.

Using  Yamaha #  3JN-24500-10-00 and you can cut the tube lower. Have 5 of them on my bikes.
And thanks Mark as that old thread was how I came about using them.

3JN-24500-10-00 is what I'm using, and it came in a Yamaha box. I also cut down the main tube. It was around $30 and works great. However many of the same model number are being sold for around $9- $13 in unbranded boxes. Personally, I'd make sure to purchase one in a Yamaha box, so you don't end up with a clone that leaks. JMHO