Engine Noise

I have a 2002 crf 450 that has just recently started making a noise in the engine. The only thing i can compare it to is the sound a skateboard wheel makes when you spin it. I have read about problems with couter balance bearings. If that may be what it is how can i tell. And how hard is it to replace them. Other than that this bike has been great. I have had very little trouble with it since i bought it.

If it is the counterbalance bearing going bad it will probably be leaking coolant out of the weep hole below the water pump. Everyone that I have heard of going bad has this symptom. Otherwise the only way to tell is pull the counterbalance shaft and examine it for wear.

My CRF450 sat for the winter & when I fired it up yesterday there was coolant coming from the weep hole. :naughty:

After the bike warmed up it stopped.

I dont hear any grinding noise from the motor?? Has this happened to anyone else or is the a seal I can change to fix this? :naughty:

Headed north next weekend & dont want to have any problems on the trip.


Left side crank bearing. honda made bad on this part, funny it will run broke but get it in and change lower bearing on crank. Mine went 4 months old got it replaced and now its been fine for 1.5 years. good excuse to change piston and rings and quick valve adj

OK I checked the weep hole after I had ridden for a few minutes and found there was a little bit of coolant along with a slight amount of oil coming from it. It wasnt much but there was a drop hanging there. Also I used a mechanics stethescope and the noise seems to be louder on the right side of the engine.

Sounds like your right side counterbalancer Bearing is suspect. It's easy to change and you do not have to pull the engine from the frame to do it.

Remove clutch side cover to access. I just did one for a buddy. You'll need (my recomendation):

clutch side cover gasket

water pump seal, oil

water pump seal, water (make sure you install correctly, orientation)

water pump shaft bearing

right side balancer shaft bearing

left side cover gasket

you'll need to remove the left side cover to remove the balancer shaft which allows you to tap out the old right side balancer shaft bearing. Be carefull to not damage your oil pump gear (plastic). WIth all the parts in hand, you can do this in an hour (I can, anyway but I'm practiced at it!).

Hope this helps :naughty:

How about the balancer shaft. I know that the right side bearing rides on the shaft will I need to replace this also?

and what about the left bearing. can it be replaced as easy or do you have to split the case to do that. I would like to replace both if i do one.

The left side bearing is a needle bearing. I would only replace it if, after you slide out the balancer shaft to the left, the bearing surface on the shaft was pitted, or had lines on it (showing wear, or a bad bearing). If this was the case, yes, I'd replace the left side bearing and the shaft. I'm thinking that you won't know this till you pull it out. Other posts have mentioned tapping out the left side needle bearing with success. I haven't had too so far. But the good news is that you can still do all this without removing engine/splitting cases....... :naughty:

thank you . i will take a look at all this as soon as i can get a chance. if anyone has any other input it would be greatly appreciated

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