Stalls off idle

rdgerber2 · Posted: June 17, 2009, 12:43 pm Post subject: Stalls off idle

I have an 82 xs and just recently started trying to get it running.

The bike sat forever with fuel in it so I started with the fuel system. I have replaced the petcock and added an inline fuel filter. I also bought the rebuild kit for my carbs from MikesXs which included a bowl gasket, float valve, float valve seat w/o ring, and the rubber cap for the pilot jet.

I replaced all these and thoroughly cleaned the bowls and passages with carb cleaner. The bike will run on full choke but as soon as I touch the throttle or turn the choke to half or off it dies and wont start.

I replaced the plugs and plug caps also.

Also I cant find the air fuel mixture screw on either carb. Does anyone have a pic they could post that would show me where this is. I have the manual and looked at the pics in it and my carbs dont have the screw the manual refers to ( I believe the pics are of a bs38 and my 82 has bs34's.)

The bike has silencers from a Harley that may be somewhat restrictive. I am aware that exhaust changes require mixture adjustment but would it cause it not to run at all off idle ?

Thanks

xsjohn · Posted: June 17, 2009, 12:53 pm Post subject: Re: Stalls off idle

Nah leave the mufflers alone..........the mix towers are on top of the carb and in front.........comes from the factory with brass caps over them .......have to carefully drill a hole (as to not bo through and destroy the mixture screw dirrectly below) and put a sheet metal screw in the hole and pull the brass cap off and discard it..........put some penn oil down on top of the mix screw and let it set........they should be reset at 3 turns out from bottoming out...........

But you need to take them out (being careful of the washer and o-ring in there and clean the circuit properly until carb cleaner comes out the 3 tinly holes in the throat...........

xsjohn

Retiredgentleman · Posted: June 17, 2009, 2:07 pm Post subject: Re: Stalls off idle

Here's a picture of your carb showing the air/fuel mixture screw location.
Sounds like your pilot circuit is partially blocked, likely the pilot jet itself.

rdgerber2 · Posted: June 17, 2009, 6:24 pm Post subject: Re: Stalls off idle

I got the cap off and removed the screws and sprayed carb cleaner for a good thirty seconds. I then put the screws back in at 3 turns each. The bike now idles on half choke and gives some throttle but then dies out.

xsjohn · Posted: June 17, 2009, 6:47 pm Post subject: Re: Stalls off idle

Hard to clean the 3 little holes in the throat that are part of that pilot circuit from your method.....but improvement would suggest that you are on the right path..........sometimes you even have to probe the 3 little holes (the three sisters Laughing

) with a small guitar string before they open up......

BS34's And another thing people don't do is when dismantling the carbs is to: loosen the main jets a couple of turns and tap on the main jet....that loosens the needle jet and it comes out through the throat....and should be cleaned including the little holes it in it.....more than 3 little holes there......more like a golf course..... Laughing

and put a bit of grease on the mix screw threads ..........and there is an o-ring on the float needle seat that will drive you crazy....four or so revs of heavy thread in the groove along side of the o-ring and tuck the end in and champhor the hole and shove it in is a permanant fix from flooding.....while your in there use a 45 pilot jet and a 135 main jet......(42.5 and 132.5)....then we can talk needles if you really want it to run good.........

xsjohn

rdgerber2 · Posted: June 17, 2009, 8:29 pm Post subject: Re: Stalls off idle

Do you have a picture of the 3 holes in the throat ?

I see three medium sized holes but there not beside each other. They are on both sides and the middle of the throat.

I must be looking in the wrong place.

xsjohn · Posted: June 17, 2009, 8:45 pm Post subject: Re: Stalls off idle

In the throat.......I don't have a pic ...someone else might......have to squint.....they are small....

Retiredgentleman · Posted: June 17, 2009, 8:53 pm Post subject: Re: Stalls off idle

I think this picture came from 5twins, but can't remember.

weekendrider · Posted: June 17, 2009, 11:14 pm Post subject: Re: Stalls off idle

rdgerber2,
Have you already cleaned the pilot jet and the passages in the bowls and body? Aerosel carb cleaner and compressed air.

rdgerber2 · Posted: June 18, 2009, 5:46 am Post subject: Re: Stalls off idle

wow small isnt the word. I was cleaning the bigger hole..I believe theres only one on the 34 but im gonna take them back off and search again 2nite. Thanks for all the help and pics.

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