fuel float level

cosack54 · Posted: August 6, 2009, 4:29 pm Post subject: fuel float level

Hey Brother Bikers! I have a 1981 XS650SH with BS34 carbs. I recently put a jet and needle kit in it from "Mikes Xs". I will be fine tuning the carbs but I need to know where I should set my float heighth. I've read different settings from a number of people elsewhere but would like some input from the more experienced riders on this site. Any help would be greatly appreciated.

Thanks!

jayel · Posted: August 6, 2009, 5:04 pm Post subject: Re: fuel float level

stock setting is 22mm± 1mm for the 81 this is measured from the carb body gasket surface a better method is seeing the actual fuel level with the drain tube and hose setup

Joseph · Full Member Joined: May 22, 2007 Posts: 767 Location: NY

Where can one get those bowl screw plugs for the 34's. Mikes lists some for the 38's, are they the same? Or maybe I'll just bring one with me to the hardware store and get something similar , a short bolt or something. I have been wanting to check my float level this way for a while. Should the bike be running when being done this way?

jayel · Posted: August 6, 2009, 6:09 pm Post subject: Re: fuel float level

not running , just gas on and in the bowl

pamcopete · Posted: August 6, 2009, 6:51 pm Post subject: Re: fuel float level

Well, the BS34's do not have a drain plug. They have a spigot instead. You can just put the tubing over the spigot.

weekendrider · Posted: August 7, 2009, 2:29 am Post subject: Re: fuel float level

pamcopete, I believe the first year the 34's had the plugs.
You can screw 3/16's tubing in the thread hole without using a plug.

Joseph · Full Member Joined: May 22, 2007 Posts: 767 Location: NY

Ya the 80's just have a plug and brass floats. I have seen the spigot on the later ones with plasic floats. I'll try the3/16 tubing method. thanks

cosack54 · Posted: August 7, 2009, 12:02 pm Post subject: Re: fuel float level

Thanks evrybody for your info. I'd like to try setting the floats as "jayel" suggested. Would I have to take the carbs off and level them in a vice or clamp of some sort? Also, I'm not 100% sure how to adjust the floats themselves . Do I bend the tang, turn a screw? As you can tell, I have delved into these carbs very little so I'm learning as I go along.
Thanks again

jayel · Posted: August 7, 2009, 12:50 pm Post subject: Re: fuel float level

you can do it on the bike but it's a PITA since you will have to remove the bowl several times to get it right (if you get it right the first time go buy a lottery ticket, I get half), just holding the carb level in your hand is good enough "Do I bend the tang," YES... make sure both floats/side are equal/level...

Joseph · Full Member Joined: May 22, 2007 Posts: 767 Location: NY

So being that I have a vacume petcock, if I put it on prime the fuel should be at top of bolw and not leaking out the airboxes?

xsleo · Posted: August 8, 2009, 12:13 am Post subject: Re: fuel float level

Correct.

Joseph · Full Member Joined: May 22, 2007 Posts: 767 Location: NY

Just spent hours getting this right with the clear tube, a few time I though I had it and left it on prime to check while I started cleaning up and they overflowed. Final nailed it though. Once I get the opportunity I am going to get new seats and needle valves. I am going to do the seat polish thing 1st though. My brass floats are bent every which way I would like a new set of plastic floats. Next job is stearing bearing service grease and check for acurate instal.

borjawil · Posted: August 12, 2009, 5:23 pm Post subject: Re: fuel float level

is the fuel level in the carbs supposed to be at the top of the bowl piece where it meets the carb body or below that or above?

Joseph · Full Member Joined: May 22, 2007 Posts: 767 Location: NY

Mine are set a bit above where the float bowl seats against the carb. Used about 4" 3/16 tubing threaded into drain of bowl and then went from that to clear tube.

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