My HS42 drips gas from the vent tube, a drop every half hour or so. Is it a float adjustment I need or is that normal?

 

the gas we have today is eating tank sealer up - if it were me i would replace the float valve and adjust the float to spec with the new valve

 

Yes. Check the float valve. May just have a little crud in it.

 

Is the float bowl gasket reusable? I'm going in.

 

most times yes // nothing falls out that you should be concerned about - you can drain it from the bottom nut first -

setting the float will require you to remove the carb and having a Mikuni book will also help -- jz

 

The gasket is a formed o-ring and is reusable indefinitely. Rebuild kits are available online. The tuning manual is available as a PDF download from the Mikuni website.

I suspect there is nothing wrong with your carb except for a little dirt caught in the float needle. this happens to mine from time to time. It usually cleans itself out. If that doesn't do it, the rebuild kit contains a new needle and a seat.

Do you shut off the petcock when you park the bike? Leaving the petcock "on" means the only thing holding back the fuel in the tank is the float needle.

 

I just started turning the petcock off when i park. I hope i remember to turn it back on. Probably run bowl dry before warmed up so wont be a big deal.

 

"I hope i remember to turn it back on."

You will remember when the bike starts sputtering as your going down the road. Don't ask me how I know.

 

Mine drips a bit brand new, kinda figured engine heat expanding the fuel? Petcock is off btw.

 

I have had the Mikuni/SE carb for close to 15 years, and it has never dripped.

This spring when I fueled it up for the first time it was dumping gas out the tube, obviously because the valve was having an issue.

When I took it apart to clean I was surprised to see how far off the float was from what it was supposed to be. It was set high and was barely able to close the valve off.

Adjusted according to spec. and all is well.

Screws were a little hard to get out, but I put a little anti-seize on them when I put it back together.

Next winter I will replace gaskets etc, but for now it is working perfect.