How do you check crank bearings?

[cnrcpla]

When I gave my top end to the dealer, they told me to check the crank bearings to make sure they were still good. So, I took the connector rod and checked for out of place movement. It has no up or down movement, no back or forth movement, and it moves effortlessly. Is there any other way to check them? I want to make sure before I put the top end back on because the dealer told me that if the bearings were shot, the bottom end would be a grenade. I want to avoid splitting the cases, so anyone got any ideas?  Thanks in advance 

[TotalNZ]

You can check your big end side play with feeler gauges, and check your main bearings by pulling of your left hand engine case and grabbing the flywheel and giving it a good wiggle to check for movement, there should be none at all.

[cnrcpla]

Oh, ok. I haven't tried that yet. I will do that, thanks 

[SachsGS]

A quick and dirty way to check your conrod bigend bearing for play (wear) is to grasp the conrod with one hand and pull up and then strike down on this hand with your other hand.If you hear a "clank" it's time to split the cases.As for the crankshaft mainbearings,pull your stator and examine the crankseal area for leakage - a sure sign of wear.

[cnrcpla]

Ok. I'm going to pull it off now and check.

[metal_miracle]

you may not feel any play if you dont remove

flywheel  and some times  you have to remove on the right side too


move spindle up and down  to check for play

[cnrcpla]

Sorry for the delay. Everything checked out ok, there were no leaks in the stator area and no play that I could detect, and since I had the clutch side open anyways, I checked those bearings to and there were no play. I also tested my radiator for leaks, and that checked out to. Can't wait to break all my new stuff in 

[william.z.todd]

i have a friends wr 200 that we are working and it has some vibration issues so i took off the flywheel cover and let it run and when you give it a little gas (in neutral) the flywheel seems to rise toward the head slightly would this be an obvious sign of crank barrings shot

[arnego2]

I use a large screw driver as leverage to see if there is movement on both sides of the crank shaft.

[cnrcpla]

I am probably going to do a bottom end job next winter (not this winter I want to ice race). My crank only the stator side had an ever so slight amount of movement to the point where I wasn't even sure if it was moving. The right side was absolutely solid.

[arnego2]

The best way is to do just all, I mean you have to split cases to do one why not doing both?
And the flywheel side is the most dangerous leak you could have. Once the seal refuses to seal at WOT you melt your piston.

I do bottom end at 150 to 160 hours, if not a bearing forces me to do it earlier.

[cnrcpla]

I had to pressure test the engine after I had an air leak somewhere. I found the leak (in the boot that goes from the carb to the reed) and there wasn't anywhere else leaking air. There is also no leaking oil, so I'm thinking the seals are fine. But, when I do the bottom end, I do plan on doing everything, bearings, con rod, crank, and everything. That's going to be an expensive bill 

[arnego2]

I think compared to the damage a failed bearing  could cause the preventive repair or exchange of parts is economical feasible.
2 Bearings if OEM come to about US$ 60 both, the needle bearing OEM about 95 incl washers. Better a con rod kit for 105 or so.
That is the minimum I use.

If you are sure there is no leak great, but a play in the bearing will make the seal fail. That is the problem. 

[cnrcpla]

So I don't have to get a new crank? If I don't that's a BIG chunk of change I can save. I will double check the stator side bearings for play as soon as I get home. If I can just go with all the bearings and seals and con rod kit, I can do that next top end job assuming the bearings aren't shot already.

[arnego2]

That's right one or two times I do just a bearing change (incl. the oil seals) and the con rod kit. I like Hot Rod.