Cylinder Heat

[ryonker]

I remember reading a thread about engine heat and something about bluing on the exhaust just out of the manifold. Outside I took a look at my pipes and the two middle ones (cylinders 2 & 3) are litely blue on the front right at the bend downward. Is this something I should be concerned about? It's possible the bluing was always there; never really looked for it before. If they are burning hotter (which means richer, right) should I tighten back the air flow screws on the carbs a little?

What do the experts think?

Thanks!

Rick

[DimitriT]

Hotter doesn't mean richer. Hotter means lean. But if your bike
runs smooth I wouldn't worry about it. My 750 has been picking
up a little gold/blue on the pipes in recent years. It can probably
use a carb cleaning as its gotten a little lumpy down low. But
the way I look at it, I'll have all winter to work on them.

[tkent02]

Could be too lean, could be timing too retarded so there is still too much burning going on as the fire goes out the pipes, maybe some other things...

Check them all so you know what is going on before something expensive happens.

Very easy to check.

[chef1366]

Pull the spark plugs and count the threads that are colored. This is the heat range. If you are too lean your threads will show color after two threads. Try to keep it under 1.5 threads.
Do a search of Lecroy. He's talked bunches on the subject.

[ryonker]

Thanks for the tip. I know for a fact the timing is retarded...for better or worse I set it that way just recently (like 2 days ago).

So, as I look at the timing area, with light hooked up to plug 1, I see

/ F1 - 4 / and I lined it up with the line on the left

for plug wire 2, I see

/ F2 - 3 / and I lined it up again with the line on the left.

So, are you saying, line the timing up in the middle, between the lines?

Am I making sense?

Thanks for you help guys!!!!!

Rick

I will be checking my plugs as well.

[chef1366]

If you are using a timing light do it with the spark plugs out and and turn the engine with the starter. This will keep the advance from advancing. The light should flash on the timing marks lined up with F1&4 and F2&3.