header temperature

[beechfront]

i have this little digital thermometer i use to tune my little gas R/C truck.

so i thought i would try to check the temperature of the headers on my xs11.

i checked about 2-3 inches down from where they attach to the engine.

here are my 'average' readings for each cylinder:

1 ~280
2 ~280
3 ~240
4 ~260

while i am not sure how accurate that guage is - #3 was consistently lower than the rest.

any idea about what these temperatures i should be getting?

would be a good way to adjust fuel mixture?

[Winterhawk]

Wow, isn't that something. Yamaha jetted some bikes richer on #2 and #3 cyl. because they say that 2 and 3 runs hotter?

[beechfront]

alright i tried this again tonight with the bike good and warm at idle and got much more consistent readings. carbs are synched.


warmest cylinder was running consistently around 310.

coldest cylinder was running consistently around 250.



each of these was an outside cylinder

is this something to be concerned about?

maybe 50 degrees at that point in the exhaust is not a big deal?

i was due for new plugs so i put new in tonight - did the full throtte/kill test. all plugs looked alike (maybe i didn't drive enough?) - just a bit darker than when i put them in.