[srosa707]

I'll try to keep this short and simple. I picked up a low hour '05 450x from my uncle. It had sat for a long time so I went through the usuals. When I tried to drain the trans, it came out THICK and green. I had to use a pick to get chunks of clumped oil out. Then, when nothing else came out, I filled the case with the overflow plug out AND the drain plug out until oil came out of the overflow but nothing came out of the drain. I fired it up and ran it for a few minutes, shut it down, and did the same again. Eventually, I got oil out but it was still pretty gross. I finally rode it a little bit at a friends house and drained it and it came out fine. Now I have cycled another round through it and all appears OK. My uncle used Honda gear oil and is a competent mechanic so I don't think it was his fault. I can only assume the additives in the oil broke down over time after being parked

Anyways, I have ridden the bike a few times for an hour+ and after a while I start to get a whining from the right side of the case. The bike runs, shifts, clutches perfectly but there is a whine that coincides with the rotation of the wheel. It does not stop with the clutch in or out, or change pitch with gear speed (shifting), but it does stop whining when the wheel stops spinning. I do not hear it in the sprocket or chain on the left side, but only on the right side of the bike near the clutch cover. Is there something on the right side of the case that rotates with the wheel? Sorry if this is a silly question. I am competent to tear into it, though single cylinder dirtbike motors are new to me. I'm more of a car/Harley guy.

[Back2-2]

Wew,,,,,That's fugly!

I would originally suspected condensation contamination - But, thinking about it some more and looking at the picture I would not be surprised if that is coolant and oil mix that sledged up. Coolant can leak past the impeller seal and get into the transmission oil. I would certainly keep an eye on the coolant level and do a couple more flushes.
Your question - "Is there something on the right side of the case that rotates with the wheel? "
Yes, that is the job of the clutch to mate the engine power to the gear train and power the rear wheel. As for the noise. Noises are very difficult to diagnose over the internet unfortunately. If you are pretty confident that it is coming from the right clutch side area, a guess would be a clutch bearing or pilot bushing that is going bad from the oil contamination. These 450's are a rather noisy engine compared to other brands so maybe you are hearing something that is normal ?
Try a couple more times of flushing the transmission after some riding and see if the noise changes. Keep a check on the coolant level and even a pressure check might be in order.

[srosa707]

Neil, thanks for the input. I did not consider the impeller as the culprit but I will inspect the coolant side of the house for issues. Regarding the noise, the whining does not change or go away with a clutch pull or gear change. It seems to keep the same tempo as the wheel speed. Yes, these motors are a bit noisy but you know when something sounds awry and this definitely sounds awry. I'd prefer not to split cases and replace bearings so If its something I can get to without pulling the motor, I'd prefer to start there.

[Back2-2]

Yes, I completely understand.
If it does not change with RPM's or any pitch change with gear changes it may not be what I was thinking.
Any chance you are hearing a rear wheel bearing ? Sound change if you apply some rear brake lightly?
Maybe try the bike a stand and statically roll the rear wheel by hand - then under power run it through a couple gears.
Few ideas for you.

[srosa707]

I had not considered that, but its a great place to start. Due to the condition of the oil that came out, I just assumed the noise was due to that. Could be a bearing though. The weird thing is it only happens after I have been riding for a bit. I pulled the bike out the other day and ripped it a little and didn't hear it. Really odd. I would assume the sound would be present in the bearing regardless of how long I rode. But its another spot to check.

[Back2-2]

Not necessarily. Many times a bearing has to get hot to start making noise.
It's just something to look into. As said before - trouble shooting noise over the internet is really tough.
You'll get it - Any chance you are hearing the intake air sound ? Maybe an air leak - hiss? - grasping, I know.
Maybe Jim or Ray will chime in and have some thoughts on this ? My internet ear is not that as highly tuned as Jim.

[srosa707]

I doubt its the intake. I have a Shovelhead so I know what those sound like

Thanks for the tips. Ill have to dig a little deeper but this is a great starting point. How often do these impeller seals go bad? I just looked over the how-to for the 450R and am assuming its a similar process.

[Aussiecrf230]

Well with the green stuff and congealed oil aI would say waterpump seal and probably the shaft as well. Easily happens when a bike sits for a long time.
CRF230s don't do that, the mud wasps make homes between the fins though.

Whe you said in time with the wheel then that would be the first think to check as Neil said.
Another thing connected with a wheel may be a speedo drive or cable.

It is surprising how a noise can appear to be coming from one spot but ends up being in a quite different spot.

Overheated coolant often goes black an oily, so often things aren't as they seem.

[Back2-2]

Yes, the intake as source of the sound is a long short - But that's what we are doing here is taking long shots on trying to guess at a noise that we cannot hear.
Ray brought up a good point - Maybe the odometer cable is squealing ? That is to the front wheel but cables are know to squeal when dry. The impellor seals go bad on all water pumps on all brands of bikes. Not uncommon at all. The seal can fail and coolant leak out to the outside weep hole or it can fail and leak into the transmission.
Static stand test should be able to help narrow it down the noise. A pressure check and watching the coolant level, which you should drain and flush anyway since it has been sitting so long will tell you if the pump seal is ok.

[srosa707]

Thanks fellas. Looks like I'll be doing a waterpump rebuild regardless with this new info. Ill keep an ear out for other culprits for the whining as well and will report back if/when I find it.