1980 Xs650 special 2 issues running right

[nj1639]

Next time you have the air filters off the carbs, do a drop down test for your carb diaphragms.
Costs nothing but time to do.
With the filters off, reach into the bellmouth of the carb and lift the brass slide with one thumb and then cover the crescent shaped hole at the top. Release the slide while the crescent is covered and note how fast or slow the slide drops. Check the other carb, compare the results.
The slides should drop slow, creeping down.
Anything other than slow could indicate a leak in the diaphragm .
That can affect top end performance.
Remember, costs nothing but time.

 

[Jim]

When I rode it down the road it pulled good through mid range and but once I got to full throttle it would sputter and run bad.

Different people have different ideas what "mid range" and "top end" mean. Give us some numbers... 5000... 7000 revs?
Also, still the stock BS34 carbs? Have you done a slide drop test?
Don't get me wrong, we still need to make sure ignition is up to snuff, but stuff like a slide drop test is pretty easy to work into the process.

 

[Holloway321]

Different people have different ideas what "mid range" and "top end" mean. Give us some numbers... 5000... 7000 revs?
Also, still the stock BS34 carbs? Have you done a slide drop test?
Don't get me wrong, we still need to make sure ignition is up to snuff, but stuff like a slide drop test is pretty easy to work into the process.

Ok so it's been a little while so I can't remember exactly what rpms I was at I just remember it was full throttle high in rpms that it was stumbling. They are stock carbs and no I haven't done a slide drop test. There's not much on this bike that isn't stock.