Topic: Burning Holes in Pistons!

[Zeke]

I'm still trying to figure out if my bike is running a bit lean or not.  Tonight it seemed to be running good, but maybe a bit lean since the RPM jumps slightly when I cock and release the throttle.

I haven't changed the stock jetting since it ran great last year -- but I did rebuild carbs so I'm working on pilot adjustment.

Lets say that my pilot adjustment is too lean -- but my mains/needle is the same as it ever was, as is the exhaust and airfilter.  Is there any way that I could overheat and burn up the engine?  I'd like to ride it to work immediately whilst working out the pilot adjust but I'd like to know that I can't wreck it since I haven't changed any of the main jetting characteristics.

I've been fooling with it and when I check the plugs they have a tan - grey arm, white electrode, and a dark colored rim.  I've ridden about 20 miles on a fresh rebuild.  Plugs are new, maybe 15 miles -- is that enough to color them?

Thanks again SOHC brothers.

Zeek

[Terry in Australia]

G'Day Zeke, what bike are we talking about? Anyway, unless you're running CV carbs, your pilot circuit only controls the mixture from idle to low Rpm, then your main jet and needle takes over, so you'll be fine to ride it mate, no worries. Cheers, Terry.

[oldbiker]

Are the holes burnt or knocked. Overadvanced ignition can cause holed pistons as can preignition caused by too high a compression ratio or excessive carbon build up.

[Zeke]

G'Day Zeke, what bike are we talking about? Anyway, unless you're running CV carbs, your pilot circuit only controls the mixture from idle to low Rpm, then your main jet and needle takes over, so you'll be fine to ride it mate, no worries. Cheers, Terry.

Hi Terry:

These are regular 'ol slide carbs from my 80 650 -- That's what I thought, but I wanted to hear you say it!

After putting in so many hours (and $$$$) rebuilding it, I just wanted to be sure.

Thanks!!

[Zeke]

Are the holes burnt or knocked. Overadvanced ignition can cause holed pistons as can preignition caused by too high a compression ratio or excessive carbon build up.

Hey Oldie:

It was a "what-if" question.  Just wanted to make sure that I could ride it the 60 miles to work and not worry about it.

Thnkas

[Terry in Australia]

G'Day Zeke, what bike are we talking about? Anyway, unless you're running CV carbs, your pilot circuit only controls the mixture from idle to low Rpm, then your main jet and needle takes over, so you'll be fine to ride it mate, no worries. Cheers, Terry.

Hi Terry:
These are regular 'ol slide carbs from my 80 650 -- That's what I thought, but I wanted to hear you say it!
After putting in so many hours (and $$$$) rebuilding it, I just wanted to be sure.
Thanks!!

No worries Zeke, enjoy that ride! Cheers, Terry.