Troubleshooting of first ride gone wrong.

[Lou Ranger]

Could it be another form of fuel starvation - namely running on the lean side now that you have sorted all the rest out?
Some old timers have told me that the original factory tuning was set on the very edge of the spectrum on the lean side and, that from one day to another a particular engine can move back and forth over the line, as it were, depending on humidity and temperature combos.
When "over the line" it manifests like an irregular "miss" when accelerating at w.o.t. at high rpms.

 

[birk]

Okay, long time no see!
But much of that time, have been invested in the bike and let me just give an update;

Willem:
As i earlier said, my first try on fixing the "black start plug" prob. was to adjust the float hight, this only let to a starvation when reaching around 80 km/h, also my mechanic says that the float hight has nothing to do with the fuel injection so yea.. I still haven't figured out what happened since I lost power, but I just downjusted them again and it I worked. My startplug still turns black by sod. I have also changed the main jet! This is the left carburetor and cylinder -the right cylinder works just fine.

chris:
Here you go!

Luckily that wasn't it.

Lou Ranger:
Since my last post, the sound and balance of the two cylinders have improved immense! But im still certain that this is a matter of too rich of a mixture?

Just some extra info;

I Have also checked the main Jet size and this might be interesting. The size was 132.5.
In the Hayns manual, the xs360 has a 135 and the xs400 is said to have a 142,5? It runs fine on the right so I don't see a problem, just thought you should know.
-also checked the choker jet.

And a bonus question; does the idle mixture screw have anything to do with an uneven run on the cylinders when speeding or only when still?

 

[birk]

so... my headache is the plug that still seems to get a too rich mixture, but how, I cant say?

 

[Scorpio1963]

Have you checked the gap of the plug?Also is there a difference of spark strength from side vs the other.The plug that is ruuning rich may not be getting a hot enough spark to burn all the fuel in that cylinder.

 

[birk]

Yep, and the plugs are the same.
But tomorrow i'll try and put a new pair in. One of the types that's mentioned in the Hayns, BP7ES I believe.

 

[Scorpio1963]

You took and rebuilt your carbs I assume,I know the answer probably yes?When you took out the mixture screw did you get the small little rubber washer out on both sides,Im thinking that one of your mixture screws might be seating deaper than the other one so when you turn them say 2 3/4 turns the other side where your problems actualy maybe turned out farther than what you think like maybe a extra turn.Try leaning out the one side that gives you the black plug by a turn and see if it makes any difference.

 

[xschris]

Have the carbs been synced with a manometer?

 

[birk]

I'll try the mixture screws but

And a bonus question; does the idle mixture screw have anything to do with an uneven run on the cylinders when speeding or only when still?

Yep manometer have been on and synced.