Ball bearing fouling a plug, lol

[ThorBell]

83 250r, Clean bike that I rebuilt case up last year. The bike has had probably a dozen long 30-60 mile rides on it since, and still runs perfect. But, the last ride while climbing four peaks mountain here in AZ, I fouled a plug. No biggie, right? its only the second plug I ever fouled... When I pulled the plug I was surprised to find what looks like a 'bb' or a ball bearing wedged between the proceline, *spl, and the outer electrode. It was oviously small. When I changed plugs, walla! instant fire and ran like nothing ever happend. I finished my ride, all the while waiting for it to grenade under me, but it didnt. I figured once I got it home, I would resplit the case and rebuild it. But now I'm wondering, where the hell did that bearing come from!? it isnt a rod bearing, they are needle. It isnt the crank to case bearings, they are huge. If ANYONE has any input on where that puppy may of came from I would love to hear it. Im not terribly excited about ripping the bike apart just to find it is 100%. I did remove and clean the entire exhaust one ride before the four peaks trip. And I do have a 3yr old that loves to hide stuff for daddy to find later. My best guess is that, whatever, was in there from then and only on the four peaks did it finnally foul. Where the bb was lodged it would not necessarly short the plug. believe it or not it fit about half way up the porceline... Help?

[ThorBell]

Sorry for the duplicate, pls delete one Admins

[brapp]

well it sound sliek it could be lean and pieces of aluminum meltign of fthe piston and wedgign in the electrode. what does your ploog color look liek on the new plug? i have seen aluminum particles/ blobs in the spark plugs when the pistons start to melt.

[ThorBell]

Everything looked normal, minus the bb. A little dark greasy, i do tend to run the mixture rich 20:1. I wasnt riding it very hard when it fouled, only 25-30mph on a dirt road, albeit uphill. The bearing was wedged, not melted in place. When I tried to free it it fell into the dirt and was lost forever. It looked pretty round. But based off what you said I think I'll pull the head though. Anyone think that it could of been a real bearing? Thanks for the quick response!

[brapp]

not unless someone put shotgun shot in your motor. they dont use anythign that smallin a trike. and i ahve seen it a piece of metal melts of fthe pistona nd bounces around and cools rapidly and wedges in the plug. i ahve seen it before
and 20 ;1 is aweful rich dependign on what kind of oil your using. it could be runnign lean and just look rich caus eof the amount of oil your runnign i have all my pingers set up to use 32;1 or 40;1 dependign what thier used for.

[ThorBell]

The manual called for 20:1 but the guy I bought the bike off had been running 50:1. I just didnt want to be one of the guys who locked up the cyclinder running it flat out at max speed one day. I will lean it out to 32:1. I will pull the head and jug and inspect/clean it. Maybe that way I can look for any damage. I wish I took a picture of the bb, it sure was strange. It had to of come from somewhere... If I find anything i'll let u know. Maybe I'll pull it this weekend. Thanks!

[Brad200X]

The manual called for 20:1 but the guy I bought the bike off had been running 50:1. I just didnt want to be one of the guys who locked up the cyclinder running it flat out at max speed one day. I will lean it out to 32:1. I will pull the head and jug and inspect/clean it. Maybe that way I can look for any damage. I wish I took a picture of the bb, it sure was strange. It had to of come from somewhere... If I find anything i'll let u know. Maybe I'll pull it this weekend. Thanks!

Remember that was in '83. 2-stroke oil is WAY better than it used to be. 32-40:1 is what all machines can run on nowadays. I think we run 30:1 (My Bro mixes the gas so I'm not 100% sure) Lots of guys run 50:1, and I've heard of people running 70:1!

[ATC-Eric]

Also remember that just because your running 20:1, you can still melt a piston. You need to get the carb jetted correct.

[ThorBell]

I just have a hard time believeing the carb isnt jetted correctly. This bike has hundreds of hours on it. The guy I bought it from had ran it at the dunes, glamis, for years. I've had it for over a year and have ran the hell out of it. I live at 1k feet and was at around 3k when it had this issue. If anything it should of been running rich. But ya'll maybe right. I will update this just for everyone's knowledge once I pull the jug. Thanks for everyones input!

[Erics350x]

im not sure if your carb has em but, maybe it was a check ball outta the back of the carb?

[ThorBell]

Well, tell me what causes this! Im thinking 26 years Anyone know how hard the 300 conversion is or where to pick up the parts? What about 30-60 over bore? what CC would each put me at? The jug is perfect, no damage at all and I couldnt find any parts of the piston in the exhaust. I think she ate 'em and poo'ed them out on the trail. Good girl! Any experience/advice would be GREATLY appericated! GG!

[300rman]

just long overdue for a rebuild probably. but, the molten metal in the plug could mean you are jetted too lean. re-jet the carb.

read the jetting 101 thread in the world class help forum

[brapp]

and a lean motor will softent he aluminum of the piston also. i would split cases and make shure or most lilely replace crank berings, rod berrings and while your in there crank seals and also make shure your pipe doesnt have any little metal fragmants in it. that can be sucked back into the motor. and i wouldnt go any bigger then needed to clean up the bore. and a good mix to use is i run klots benol at 16 ox bottle to 5 galons of gas in alot fo mu trikes. just not good for cold wether use. but check your plug and figure out where your jetting is on top
bump up the main and se eif it bogs or a slight bit of choke will also help tellyou if its a little lean..

[ThorBell]

just not good for cold wether use. but check your plug and figure out where your jetting is on top
bump up the main and se eif it bogs or a slight bit of choke will also help tellyou if its a little lean..

A little clarification,

1. "not good for cold weather use"? too little oil or too much for cold weather?
2. "a slight bit of choke will also help tell you if it is a little lean"? how? when choked, it would run but wouldnt want to rev up very high.
3. What should I be looking for to tell me if Im lean? The plug was always oily black but I was running oil rich. I fear re-jetting and making it to rich for the dunes, glamis.
4. Again, sounds like everyone is against the 300 cc conversion. nobody think it is worth it?

From looking at the exposed bearings, upper rod, I saw no signs of damage or debre's. Honestly, I was thinking of dropping a new piston in it and slamming her back together. I inspected the exhaust and could not find ANY parts of the piston. I can crack the case, its just alot more work... slackr, I kno!

[brapp]

the klots benol seperates and is good for top end it has a higher film strength.


and if it still runs cleanly when 1/2 choked or full choked it is severly lean.

and look for anice carmel color on the plug if its a bit on the white side your lean and the 300 conversins arent bad but a pita to find parts for soemtimes.