Jet Kit

might be something to do with the petrol feed going through the left carb and supplying the right!
Jetting has nothing to do with filling the carb bowls - it's about getting the right fuel air mixture. My bike a DOHC and the jetting may be different than the SOHC engines. I just picked up on the Euro richer over the US leaner jetting recommendations. I'm running stock exhaust with pod filters.
 
Here's the skinny on the staggered jetting issue. Grizld1 from the XS650.com said.
"the primary side is the hot one, and that's the left on the old Brit twins and right on the XS650. Vertical twin race bikes were often stagger-jetted, with a fatter main on the hot side".
 
Learn something new every day! I wish I knew this when I was making sure the motor ran before i tore into this thing. For a while I was only hitting on one cylinder. I got them both to fire and then started using a non contact thermometer to measure the temp on both sides of the exhaust at the head as a way to make sure both cylinders were making power. One side would read a higher temp than the other and I spent days playing with float levels, checking coils etc trying to get the motor to run at the same temp on both cylinders. I'm going to have to do some reading up on this primary cylinder thing.
 
you might have to change the needle setting on the slide by raising it up a notch.( or more, first notch on the needle is leanest and 5 notch is richest) this will make it richer in the mids. also you might want to put larger pilot jets (45) and reset the air mix screws so it idles rite. it should pull stong all the way to the red line with no
"dead" spots. then check the plugs for a little carbon on them always go a little richer than lean so the engine dont run to hot, remember lean is mean!:thumbsup: i have done this with my 650 but not my 400 my guess is they wont be much different.
 
son of a b...well this bike i bought already had pods on it, and i have no idea if it was re-jetted for them. apparently it was running fine before it sat for 4 years, but now i cant get it to fire good on the left cylinder. it idles fine on the one cylinder, and when you give it throttle it will run better and backfire. could that be a jetting problem? should i buy all new jets and start from scratch?
 
son of a b...well this bike i bought already had pods on it, and i have no idea if it was re-jetted for them. apparently it was running fine before it sat for 4 years, but now i cant get it to fire good on the left cylinder. it idles fine on the one cylinder, and when you give it throttle it will run better and backfire. could that be a jetting problem? should i buy all new jets and start from scratch?
Your jets should be marked with their sizes...
 
son of a b...well this bike i bought already had pods on it, and i have no idea if it was re-jetted for them. apparently it was running fine before it sat for 4 years, but now i cant get it to fire good on the left cylinder. it idles fine on the one cylinder, and when you give it throttle it will run better and backfire. could that be a jetting problem? should i buy all new jets and start from scratch?
Have you cleaned your carbs properly? By that I mean blow out every orifice, push out the needle jet and make sure all holes are clean, set the floats, etc. It will not run unless you do this.
 
i have torn both down completely, removed all jets, drenched everything in carb cleaner, ran guitar strings through them all and every hole, and blew everything i could find out with my air gun. ive done this multiple times, and each time it runs better and better. i think it needs to just get out and up to speed, but i was worried that i would burn up that cylinder if i did that. but its to the point that i may have to.
 
When you say all jets, including the one that runs down the center of the carb. You have to press that out.
 
all jets that unscrew and come out, including the plunger and the needle jet. the spark seems strong on both sides though so i dont think that is a problem.....new plugs too...
 
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