Needle Bearing on Wrist pin Loose?

Russntustin

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I'm in the process of prepping a new engine.....I pulled the head and jug.
(replacing all the studs, want to clean-out the holes in the case)
Anyway....I see that the needle bearing on the wrist pin just FLOATS back and forth. (with the piston on there) This doesn't seem right. Although I don't see how it's supposed to be 'pinned' or anything. I mean it slides/floats 1/2 way off the piston but not ALL the way off.
This normal? ?
THANKS!!!
 
Yes, it is normal.

I use a couple of "wavy washers" to help keep the roller bearings and cage centered on the rod. I don't know if it actually helps, but it makes me feel better!
 
I blame the fact that the bearing can slide back and forth a reason I blew an engine last summer. I had to take a nature break and left my bike on a side kickstand for about 5 minutes while it was idling. I feel that this allowed the bearing to slide out partially which puts an unusual load on it. After my break, I took off and went full throttle down a hill. The bearing cage fell apart and destroyed my top end. I think the bearing was still off to the side when I put a higher load on the engine. This put destructive forces on the race/cage and whamo...instinct engine death.
 
Arceeguy.....Do the wavy washers you put on move also or do they 'squish' on and stay in place?

Skyliner....Jeeps! So what did you do to fix this??

Thanks so much for the help!
Russ
 
The washers float on the wrist pin like the bearing cage. The cage does still have the ability to shift around, but not nearly as much. Just measure your piston pin diameter (10 or 12mm) and go to your local hardware store.
 
side slop or up and down slop

Thanks....
I mean this bearing cage comes half-way out of the con-rod!

that's true -- but

won't it be held in perfect place when in the cylinder ?

you can use spacers if you wish
just don't see any reason for them

maybe I am missing the picture ?

it's up and down slop that TRULY matters

love that THING
 
I think the problem is that on some kits they don't drill oil holes for the bearings.

BSA
 
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