Carburetor float question

[Revnelli]

Hi,
I have a drz and am putting a clarke tank on for next season. I found a replacement second-hand vacuum petcock. Once I had everything tightened up (Tight!) it seems to have only a small (1/2 cc per day) drip.

So here's the question - Is having a petcock somewhat redundant when there's a valve in the float tank?

Specifically for me - Given that the carb (in my case a Mikuni BSR) has a float valve which should shut off excess fuel, do I need to worry about this slight fuel drip (I read the horror stories of fuel drips from vacuum petcocks destroying engines)?

Update - posts on Thumper talk suggest the drip needed to be fixed - or another petcock. Dismanteled the petcock and cleaned it again - this time no drip - YeeHa

Thanks for the help

Neil

 

[Can-am Kid]

Neil,

The problem with by passing the petcock is that the float valve is not perfect and can leak. You go to fire up the bike after a week of sitting to find the cylinder is filled with gas or it has leaked gas out over the floor of the garage. This happened to my DRZ until I found out the seal under the needle valve was shot.

If you are looking for a replacement for the stock vacuum petcock ($150.00 for replacement) one off a Yamaha Raptor is a perfect fit and only costs $48.00. I used one off my old Can-ams for a while until I found the Raptor petcock.

The Kid