Ok I am going to need some help reading my plug out of my NY Pilot from yesterdays ride. The Engine went poofkaboom on my ride back to camp. I was driving down a long straight away, off and on the throttle,and it just complete shut down.Tryed to re-fire, the motor (( Internal Combustion Engine ? )) is turning over fast and backfiring every once in a while-typical when I have in the past leaned out an Engine and seized the rings onto the piston.
The Engine is a fresh rebuild from Hoser(the cracked case Engine which we lost all documentation on with the hack), Boyesen reeds,stock carb,I believe we were running a 80mm Wiseco,stock head,102c clutch,Paul Turner full exhaust.
I adjusted carb from bottom up and had several hrs of break in on the Engine prior to the ride.I will post pictures of the plug here starting with the plug chops on break in first.
Now I was reading the spark plug information here in the tech pages and in a recent thread here:

viewtopic.php?f=1&t=5587" .".." .".." .".." ."..

Going on the tech supplied here I did exactly what adnoh had and measured my smoke rings on the plug out of the Engine. More to come on that.
Here is a picture or 2 of the plug chops during break in:

Here is a picture of the plug right after the Engine shut off on me. The measurements are provided of the smoke ring as well. What did I do wrong? Did I lean the Engine out? The smoke ring is larger then the posted ADNOH measurement of 0.80. The porclean is light brown-the top indicates in my opinion proper heat range as well but I am doing something wrong. ANY HELP is graciously accepted.

Temp yesterday was in the high 40's and sunny. I am using a single intake with a UNI FILTER. Needle is on middle clip stock internals on the carb 140 main jet on stock carb.Fuel was EXXON premium 93 octane HP2 mixed at 32:1.

For others here is the plug reading thread hopefully it might help some
viewtopic.php?f=9&t=870

Refresh me on this Engine and Pilot and mods, you have a link to this project?

I am trying to locate the rebuild of the Engine but I think the thread went by by in the hacking.Here is a link to the project:

viewtopic.php?f=34&t=9251" ."..

It does not include the Engine rebuild however Hoser. Sorry.

The plug look fine with the exception of a few specs of debris. Sorry to here it went away on you. I sure "H" will do a full CSI and get to the bottom of it.

I did see the debris. Could that be from the rebuild? They do look metallic in nature to me.
Compression check reveals 40 psi. No good indeed. I suspect the debris is from the rings or piston seizing after this check.
Any idea Adnoh what I did wrong? Hoser thinks the Paul Turner full exhaust may have leaned the Engine out on top end perhaps. I have never used one of these full exhausts before. Could this possible be a culprit?
I am going to remove the top end today and CSI what the hell I did here. I am sick to my stomach again today after this.

Engine rebuild must have been lost in the server hacking? Bastards!

Good eye on the aluminum specks adnoh that cant be good.

After chatting with Mudbogger in the chat it might be as simple as too lean on the top end or mid-range that caused the poofkaboom

From the chat room "Mudbogger the Engine did seem to hesitate at high idle for a 30-40 sec before dropping after a long wide open run"

When you stop and the Engine wont return to a normal idle or idles high its usually a indication of high combustion chamber temps, a quick test is to pull the choke at idle this dumps more fuel in and cools the combustion chamber really quick then the idle will return to normal almost instantly then its time to figure out where your lean it could be in the mid range or at WOT (Wide Open Throttle) check them both.

This high idle thing can also be caused by a bunch of carbon deposits on the head or piston or too high of a heat range on the spark plug, this Engine was fresh so we know it was not carbon and he was running a BR8ES plug which is actually a colder than required plug.

What I usually do when I buy a new to me machine is raise the needle (lower clip on needle) all the way to fatten up the mid range and go up on the main jet until it blubbers at WOT (Wide Open Throttle) then work back down so I know exactly where I am with the jetting.

Last I talked to Mudbogger in the chat room he was off to take a compression test.

Thanks for the help Hoser to determine what went wrong here. As stated in the chatroom the idle did right before the poofkaboom stay high for 30-40 seconds then dropped to normal. I did not think at the time to do as stated"pull the choke to get fuel into that cylinder" and hopefully will never forget to in the future.
Top end is off and it is toasted for sure. Pictures in a couple minutes. The piston was a fresh 81.5mm Wiseco so at this point I think I will just forgo a bore and send this to be re sleeved.
Pictures of the piston are here, cylinder will be forthcoming.

To me its a bit on the lean side for top end or mid range. For mid range since that's where our engines mostly run I like it close to black and on a top end chop closer to brown.The shots of the plug was after the Engine went? Or is this the plug after a chop? when you do a plug chop do you do it on midrange and top end so 2 plug chops? When did it go topend run of after you let off or when you were cruising?

Yes the second set of pictures of the plug are right after it poofkaboomed yup.
I do do plug chops on mid range and top end yes using fresh new plugs as I constantly adjust needle settings and such during the jetting.
The Engine went when I was on the throttle full throttle to be exact-it just shut down. I did plug chops on top end prior to going out and the plug was a light pancake brown. The main was a 140 -single inlet air intake-all stock internals-81.5mm Boyesen reeds.
More pictures of the piston:

Any pics of the cylinder wall and head?

Here you go Hoser. Pictures of the cylinder. Your thoughts on boring this to 82 mm or re
sleeving it.
Funny Hoser. look at the the first picture. This is the jug off the 2800 Pilot motor (( Internal Combustion Engine ? )) you rebuilt!

More pictures.
Does this jug look to be re sleeved?

My question now is how do I determine using these pictures if I went lean on midrange or full throttle?
I was on a full throttle run when it actually blew up-but the trip had been on and off the throttle most of the trip in tight trails.

Doesnt look like a lean blow up. Looks like a 4 point cold seizure or too hard on it before it was broken in all the way. Looks like the piston warmed up faster then the cylinder. If it was lean on topend your piston crown would be sunk alittle or your exhaust side top of piston would be melted away. Are your rings pretty free?

Well, on the areas that are not siezed yes. Hard to tell though you know?

Man that does not look good. It does show signes of a four cornor with a twist. Since you had to pound out the pin that tells me it out of square and the piston deformed.

Man I may need to let this soak in a while Theres a lot of things that just don't look right with a new rebuild that had all that damage and discoloring ect. I really think "H" will need to take a close look at this one. Did this one have a crank rebuild ? I have seen simular but in an ody. What head ect. Was that a rev pipe with the stock port timing? Not normal for sure. Carfully clean the black off the base of the plug and check the ring again.

Hello Adnoh.
Yes this has a PRO-X cr 500 rod kit in it and the small end was milled by Speedchaser to allow proper lubrication/fitment of the piston.
Head was stock OEM. Engine had a 102c clutch with a Paul Turner expansion chamber with FAT BOY silencer. Port timing I will refer you to Hoser, he built the Engine for me but I believe it was stock. Due to the hacking we cannot access the thread on this build which really hampers abilities to pinpoint the exact issue.Hopefully he can be of assistance for you in regards.
The discoloration was a surprise to me but the pin being so hard to get out as well really threw me off. The burn pattern as well seems off.
How should I attempt to clean that plug with a light brush such as a toothbrush?
I might add I do have another PRO-X rod kit in my 2800 Pilot Engine with the same milling on the small end and it has not had any issues to date with about 20 hrs min on that rebuild.

The jug is from my 2800 Pilot project which was previously owned by FACTORY 45. I do not remember Hoser mentioning anything about the jug but the old Engine from which this jug was removed from was rebuilt by FACTORY 45 before purchase. The reason for the rebuild was the crank twisted if my memory serves me. Is this information helpful?
I remember Speed had a real bitch rebuilding the crank on it as well from what I remember--but mabye we can speak to him in regards as well when he gets back from ALASKA.

Is the cross hatching smoothe as glass or is it still a little rough like a fresh hone?

How long was your ride before it pooked?

Did the circlip pop out of the piston? I have seen that happen on a vehicle brought in by a customer with a Wiseco pison to a shop that I worked at before. Was the piston a Wiseco? That sucks man.

After looking at the pics some more it looks like the rings arn't seated yet. You can see some blow by on the pics of the piston below the botom ring line. It looks like It wasn't broken it yet before you held it wide open and the piston expanded way faster then the cylinder causing the failure. Throw a hone in it and see how deep the scratches are. You might get lucky and just need the same size piston. What was your break in process?

Piston was indeed a Wiseco yes. The clips however did not pop out of the piston. Both were intack. I also are thnking the break in did not seat the rings well at all as you can still see the cross hatching in most areas on the bore.