blown bearing stuck to oil drain. identify?

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so i drained my oil, and found this: see pic :)

part of a bearing cage, and tiny (1mm) ball bearings. razor blade for scale - nope it wasn't in the oil :) - water pump or power valve shaft have bearings that small? - it's the only thing i can think of that it could be... i'm gonna pull down and investigate.any hints as to what the cause is?


oildrain.jpg
 
i looked at a spare set of cases i have laying here, the individual bearings that came out of drain are a lot smaller than the bearings in the case for water pump or pv governor shaft...


could be the inner clutch cover bearing that the pv shaft rides on... i don't have a spare inner clutch cover to look and see.. but the pv shaft is 8mm, so the o.d. of the bearing has to be bigger than 10mm..

oildrain2.jpg
 
ok. i've removed clutch, inner clutch cover, waterpump etc. everything looks fine inside.

aside from the broken waterpump impellor. and of course the bearing pieces stuck to the oil drain.


all bearings look good. where the heck did the broken bearing come from???
 
Bearing fairy?


The only think i can think of is powervalve...but 10 mm OD is really small.

I just looked through the parts fische, and can't find a 10 mm OD ball bearing.

I have no idea.
 
blitz11 said:
Bearing fairy?


The only think i can think of is powervalve...but 10 mm OD is really small.

I just looked through the parts fische, and can't find a 10 mm OD ball bearing.

I have no idea.
Click to expand...

you and me both.

the split wp impeller may be a problem in and of itself - and should have nothing to do with the bearing in the oil. testament to the need for aluminum impellers. thankfully i have one i can rob off another motor.

i am tempted to flush the crankcase, button this motor back up and call it fixed. what is the smallest bearing inside the motor? i would assume it's the impeller or pv shaft bearings, and they've gotta be close to 20mm o.d. and the loose balls in the cage gotta be 2 or 3mm at least.

i don't even know how a bearing like that could have gotten into the oil. goes to show, you gotta tear stuff down when you buy it used, to investigate.

bike was running fine - i just raced it for 2:30 on sunday, and it never had a problem - no funny noises, no overheating (70 degrees out). nothing out of the ordinary.. i'm assuming the impeller still spun, just not well.



if anyone has any idea of where the bearing could have come from, aside from sabotage :) let me know!
 
Last edited:
Could someone have punked you? Previous owner stuck a bearing down the filler hole, dropped it in during a rebuild?

Man. That is weird. I really have no idea.
 
maybe. but when i pulled the clutch hub nut, the lockwasher was factory new. never been off. don't know where you'd stick the bearing in the crankcase...i don't think it would fit in the oil filler hole. maybe it would. rebuild would mean split cases, or at least clutch pulled. it looks like neither has been done - unless a new lockwasher was used.
 
Kids haven't been playing in the workshop?? Any chance it could have been in the pan prior to dropping the oil?
 
There is no ball bearing that small in the design of the engine. Thats something that you would find in an R/C car. The left PV drum, governor, and water pump shaft share the same size bearings that are the smallest. I've had them apart down to bare cases and complete bearing set replacements enough to know. This is weird. It had to have been put in there.

The impeller is not uncommon. I swap an LTR impeller in ASAP. No more LTR impeller but I believe checkpoint makes one now.
 
How strange

Would it fit in the filler hole? Only other thing I can think of is if you accidently had it on the plug last time you installed it. Any chance last oil change was done in the dark?
 
Um... maybe I'm half asleep in the middle of the night...
but we're talking 2strokes here...

...wouldn't it be transmission parts in the oil, not motor parts?
Maybe some little selector rod for the shift mechanism rides in a bearing?

Which bike is this?

-Dean
not an expert:eek:
 
2007 ec300

i 've had several gg motors stripped to the cases, and am pretty darn sure there's no bearing that small. by my rough calculation, it would have to be on an approx. 4mm shaft. the only thing that small is pv actuator pivot linkage and i know that just rides in a bushing/no roller bearing.

A: bought bike used.
B: this is my first oil change on this bike - only had bike for 2 weeks - the only thing i've done to the motor is : change pv cover, change exhaust, add fww, and change spark plug. so there's no way it got in there from that way.
C: previous owner must have dropped it in oil filler hole. there is no other way for it to get in there. it would not fit through the clutch cover, unless the clutch was removed. it appears the clutch is all original and never been serviced (as far as i can tell)

D: sometimes there's just no rational explanation for things......


it's a tiny little bearing, i've never seen any roller bearing this small in any motorcycle. it does look like an rc car micro bearing.

i'm flushing the trans, and putting it back together. bike ran great with the bearing bits flopping around in the trans :) i've looked into trans with tiny inspection mirror, flashlight, etc. and i see no damage. the oil wasn't even sparkly when i drained it. i'm more worried about the tiny 1mm bearings, the cage and stuff is big enough to end up on the oil drain plug. them tiny bearings could stay in suspension...... and they are magnetic bearings, thankfully.
 
can you contact the previous owner, maybe he can shed some light on this?
maybe he has lil' kids that were running around when daddy drained the oil an kiddo's found something funny to put in the funny little hole :D
once heard of a guy who's engine began ratteling after an oil change, turned out his kid dropped some bolts in the open exhaust :eek:
 
hannesd said:
can you contact the previous owner, maybe he can shed some light on this?
maybe he has lil' kids that were running around when daddy drained the oil an kiddo's found something funny to put in the funny little hole :D
once heard of a guy who's engine began ratteling after an oil change, turned out his kid dropped some bolts in the open exhaust :eek:
Click to expand...

I was thinking the same thing and remembered a customer that pulled enough sticks out of his car's gas tank for a good sized bonfire.
 
Here's my theory.

The bearing was laying on the work bench.
Oil plug layed close to bearing.
Bearing got stuck to plug.
Owner screwed plug in, not paying attention.
 
Slagathor said:
Did you ever figure out what it was? I think I have the same bearing stuck to my drain plug
https://share.icloud.com/photos/0e5HBDBlzSAUi9kgF4GXseuyg
https://share.icloud.com/photos/05ayTrWSso9kx9qzENEmWHR6w

You are not alone
Click to expand...

That is so odd. I would vote for the "magnetic plug picked it up on the bench" theory - except that here are two bikes with what appear to be the same cage/bearing - one that doesn't exist in the engine! (GMP knows his stuff).

Since there are two bikes with what I assume is the same cage/bearing in the crankcase, I would think it must be something that happened at the factory. They're making some other product in the same area during manufacturing that uses the small bearing, and "cross-contamination" happens somehow. But these bikes are at least 10 years apart in age!

That is quite a mystery. So odd!

Jeff
 
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