what is the general opinion on roller bearings are engines with roller bearings any good?

I am confused. Compared to what?

Almost all two stroke motorcycle engines and industrial engines use roller bearings on both ends of the rod.

Bill

roller bearings are a good thing , needle bearings on the cranks are a bad thing but will work for a little while.

i'm sorry I dont mean to confuse. they are more like short peices of rod stock, 3\16 dia. aprox
not a ball bearing and I tend to think of needle bearing to be smaller than 2-56 size stock

On the engines I do they all have roller bearings to support the shaft ends and needle bearings for the wrist pin.

tim what engines are those

Flyjoe, I have had the same bearings on Echo, Toro, and Poulan. I have a machine i picked up to tear into when I get a chance that looks like a Homelite based engine. I assume the bearings will be the same but I think these have a cantilevered crank. We'll see.

Quadra and US engines up to the Q42 and US41 have a roller/needle bearings on both ends of the crank with a bronze thrust washer to take the thrust...NO problems...They run forever..If they get end play from wear it can be taken out by pushing the rear bearing back up against the crank...

Today’s needle roller bearings are almost always caged and can be handled as one piece. Years ago needle roller bearings would sometimes have a retainer or separator. However sometimes the bearings would simply be loose. Loose needle roller bearings can rub against each other creating additional friction and failure.

Bill

thats the way the rod bearings are on the qaudra and us engines are no cage.

And those 11 little rollers are a pain, but just far enough apart to not cause problems when running...My neighbor has a 35 or 40 year old chainsaw with a very early Q35 in it...It's so old the spark plug faces the front with a 2 inch wire from the mag coil...When it finally quit running I put new rollers on the crank and now it's still going strong...

so I take it that roller bearings are o.k. . I think I may have a new project.
38cc(2.3c.i.d.) what prop to start testing? this is the one from montgomery wards chain saw
durring inspection I found a nice little dome top piston thats like new just a speck of carbon
now a thrust washer fell out, I believe it goes on the crank at the front ,on the main jornal
behind front main bearing any opinions on this are welcome as it fell out before I could see
where it came from.
oh yeah ,its loose roller bearings on crank and main bearings ,what prevents thrust from
ruining the bearings?

There should be a bronze thrust washer in there somewhere..The load on a chainsaw crank is not thrust, but something is needed to keep the steel crank from rubbing on the steel bearing as it runs..It goes on the shaft between the crank web and the front bearing...

those needle bearing s do work for those engines and boy are they a pain .

rcign1
thanks thats what I needed to know

ken
your not kidding about that "pain" thing it took me 30min to reassemble it after all
those little devils fell out ,least I didnt lose any!

hey, how about a prop suggestion to begine testing with?