XS1B Stall at idle and flood at full throttle

jmartini

This one is strange, but perhaps someone will know what could cause it. These carbs are freshly rebuilt. When at idle (almost always with a car behind me) my bike will occasionally stall - without warning - almost like the key was turned off. Kicks right back on with no problem. The carbs are original to the bike and the the jets are correct. If I'm out on the open road accellerating smoothly it runs like a champ, but pull the throttle all the way back wide open and it starts to flood out the carbs. Can this all be caused by bad slides? Do the passages in the carbs ever get corroded (where you can't see them) to the point where the mixture is unable to be adjusted properly due to air flow not being correct? Thanks for any insight you might be able to give me. John

5twins · Full Member Joined: Aug 05, 2006 Posts: 1616

What idle speed are you running? The spec is 1200 RPM and these bikes need that. Set it lower and they will just up and stall at stops for no apparent reason.

I'm not exactly sure what you mean by "flood out". Are the carbs over filling and pouring out gas? Or is the motor just breaking up under large throttle applications?

jmartini

The idle is set at about 1300. Yes, the motor is just breaking up - no gas pouring out of the carbs.

5twins · Full Member Joined: Aug 05, 2006 Posts: 1616

Have you inspected the inside of the needle jets, the part that the fuel flows through and the needle sticks into? They can wear out over time or be eaten away by gas residue if the carbs were really gummed up at one time. Both would cause a rich condition. Also, what position is your needle in? 4th slot from the top was the stock setting for your model. You could try playing with the needle position to see if it helps.

What Happened to 650rider.com?

Yamaha xs650