Trouble with needle and seats

Hi all,
I just rebuilt a set of VM 28 carbs off a 75 kz900. I installed new needle and seats in the carbs during the rebuild. I normally shut off the petcock, but forgot the other night and had gas on the floor from the overflow tubes. I am going to recheck the float levels with the clear tube method, but I am pretty sure the needles are seeping when the bike sets for several hours with the petcock on. Is this common on these bikes? I was wondering what the little pin on the bottom of needle's purpose is. I have never seen this on other carbs I have rebuilt, mainly small engines and a few automotive carbs. I prefer to use needles that have the rubber tip. Does anyone make rubber tip needles for these carbs? The floats were replaced at the time of rebuild, does any one have a trick for bending the tab to set float without distorting the whole float assembly, seems very chincy and would bend quite easily. I am sometimes forgetful and know that I will forget to turn off the petcock once again and would like to remedy this problem. Any advice is greatly appreciated.

for starters , this is common, and this is why they changed to a vacuum operated petcock. the vacuum signal(or lack of vacuum) shuts off the gas for u when the bike is turned of , so we dont forget.
but that said, u can try to make it seat better. it is a bit of luck of the draw i think. i had the same trouble with mine. they seem to have gotten better with time. i replaced all of the seats 2 years ago,and they still leaked. now if i forget to shut the gas off they seem to seal??

I take the needle and twist it into the seat to make sure there is nothing interfering with the fit. the pin on the end of the needle is a spring pin that will apply = pressure in the needles. some needles have rubber, some dont. make sure u have a separate fuel filter. if they still leak, try rapping on the carb with the end of a screw driver, this will help the float to jar the needle shut.
I don’t know of any great way to bend the tab on the float. It is a tedious adventure to get them set right. Make sure to use the clear tube method to measure the float level.
good luck.

Thanks Mark I'll give the twisting needle into the seat a try.

oppie501 wrote:

Thanks Mark I'll give the twisting needle into the seat a try.

There's an easier way. Take the needles and chuck them in a hand drill. Use 600 paper and oil on a flat stick to polish the cone shaped head until glass smooth. Wrap tape around the threads on the brass seat and put it in the chuck. Use a Q tip and chrome polish to polish the seating face dead smooth so the tip of the needle will seal well.

This is actually normal maintenance for these parts if you want them to seal well. You may notice the brass seats oxidize over time and get a rough surface which doesn't seal tightly. Polishing them twice a year and making sure the fuel levels are correct will prevent flooding.

NOTE: you also need to drain the tan and rinse to make sure there is no crud or water because that will really mess things up. Install inline filters to keep junk out of the carbs. Any bit of crud on the needle will keep it from sealing.