Uneven cylinder temps. Need Insight

 Thanks @Warren3200gt and @Wookie58. I let the bike run for a minute or two and cylinder 2 was still cold. Pulled the plug and the earth strap was not bent. Purchased a cheap borescope and looked inside the spark plug hole and saw no foreign objects, just some carbon build up on the piston. 



I swapped plugs from no1 to no2 with no change. Checked the resistance on those two plugs and got 5.48k on no1 plug and 5.84k on no2 plug so they seem to be okay. 

Time to pull the carbs and check for a fueling issue next?

Spray a bit of starting fluid into cylinder 2 once the engine is warm to see #2 fires up.

Have you checked if cylinder #2 plug is sparking?

Remove cylinder #2 plug from the head, and plug it into it's (#2) plug cap, and earth the plug (contact the threaded part onto the cylinder-head), and start the engine.
You should see bright blue sparks at the plugs centre electrode.
If you do see sparks, then you problem is most likely to be fuel supply (carb issue) or compression related. (valve clearance / rings)
Have you checked if there is fuel in #2 carbs float bowl?

H.

With the ball valve closed on my auxiliary tank, I drained the float bowl on #2 carb and got maybe 3oz of fuel out. I tightened the drain screw up and opened the ball valve on the tank line and let the fuel flow into the carbs for a few minutes. I then closed the ball valve again and opened the drain screw on #2 and got no fuel. Am I correct in remembering the engine doesn’t need to be running or producing vacuum to fill the float bowls? 

@howardhb I did the same process you describe about a week ago. I had (and felt) the spark on #2 with it arcing to the head. Now this was done during the day so it was bright out and I cannot say how bright the spark was. I will try it again at dusk and with a better insulated pair of pliars to see how strong the spark is. 

@F64 I did what you suggested by spraying starting fluid into the intake rubber on #2 and the idle smoothed out then rose quickly. I had adjusted my idle screw so maybe with all cylinders having fuel, it’s too high. I did feel the #2 header pipe once I shut it down and it was warm unlike prior to trying the starting fluid.

I really appreciate the tips from everyone. 

You are correct about the fuel flow. Gravity does it, even with the regular fuel tank and petcock in place. The vacuum hose to the petcock merely operates the valve. When vacuum opens the valve, gravity pulls the fuel out of the tank and into the carburetors.

 

Same issue for a while, think compression here but bewildered. 

On mine there is Res Pri On... if Res or On with a good petcock, no.fuel gets thru without vac.  On Pri Prime it will fill the bowls bypassing the vac.  If u don't have a prime on your petcock, the real experts here should answer.

This got me thinking - I just drained all 4 carbs after prime and got just under 50cc except the rightmost sitting on bike, meaning everything is good there or the one is overfilling and fills the cold pipe bowl from the common fuel rail... I think it is good, but Ill adjust that last float to make sure and do it again.