[DENBROCO_05]

So I had gotten a bottom end whine coming from the clutch side of the bike so naturally I thought it was the dreaded crank bearings. So I go through the whole motor and flush it out and put a brand new HR bottom end kit in the bike, visually inspect every single bearing in the bottom end. I reassemble to spec and with lots assembly lube and sure enough 5 minutes into break in the whine comes back. Any ideas would be appreciated. If I can figure out how to attach a sound clip I will but for now the best way to describe the whine is it is most prominent at low to mid rpm it sounds almost like a supercharger whine? does occur in neutral and gears. Maybe counter balance bearings or water pump bearing? Thank you in advance I look forward to hearing others experinces

 

[[email protected]]

I would think the higher pitched whine you describe would be from something up top. You mentioned replacing the bearings in the case, did you use HR crank bearings specifically? Those are junk use OEM. I read that the whine was before the install of those crank bearings so I will assume that's not causing the whine. But then 5 minutes after first start after rebuild whine came back, correct? Did you see any play in the connecting rod eyes, before and after install? You say visually inspected the rest of the case bearings? Did you not stick your finger in the bearings and spin them to insure they were good? Was there any metallic/non metallic or brass in the oil? Did you replace oil pump or timing chain during tune up? See any scoring on the inside of the case halves? If you didn't manually verify all the bearing functionalities, then I would think the assembly lube oiled a possible bad bearing for that short 5 minutes you got without the whine after the rebuild. and after that it became hot and dry and the whine came back.

 

[DENBROCO_05]

I would think the higher pitched whine you describe would be from something up top. You mentioned replacing the bearings in the case, did you use HR crank bearings specifically? Those are junk use OEM. I read that the whine was before the install of those crank bearings so I will assume that's not causing the whine. But then 5 minutes after first start after rebuild whine came back, correct? Did you see any play in the connecting rod eyes, before and after install? You say visually inspected the rest of the case bearings? Did you not stick your finger in the bearings and spin them to insure they were good? Was there any metallic/non metallic or brass in the oil? Did you replace oil pump or timing chain during tune up? See any scoring on the inside of the case halves? If you didn't manually verify all the bearing functionalities, then I would think the assembly lube oiled a possible bad bearing for that short 5 minutes you got without the whine after the rebuild. and after that it became hot and dry and the whine came back.

Hey thanks for the quick reply man! So yes I did use the HR bearings and I have heard thy can be problematic. When I went through the engine I got lots of metal shavings in the sump and oil filter. but nothing copper. When I took out the rod bearing honestly I didn't think anything was wrong with them but I had gotten the new parts prematurely so I put the new crank in. I actually figured the Noise was the oil sump starving because it was clogged up and it was going to be a quick cheap fix. I also had gone through the head and jug and have seen no issues cylinder looks great and no scoring up top in the cam. The one thing I am pretty sure of is that it is not a top end problem.... So I now have about 5 hours on the bike since the rebuild since I gave up chasing the noise and was gonna run the crap out of it til she locked up and there is not a single shaving in the filter or motor! So I think your right about the bearing and assembly lube, 5 minutes gave it just enough time to get that pillowy lube out of a bad bearing and start whining once it cleared out. Any bottom end transmission bearings known to be problematic and make noise before they fail?

 

[[email protected]]

It will only take a small amount of shavings to work there way into all the bearings, into everything actually. Most will say to REPLACE the oil cooler and lines as well, do to this problem. Theory being how can you be sure you get ALL the metal out, and dreading missing some and sending the metal around the motor after rebuild upon first start. When I rebuilt, I didn't want to crack the cases again so I went ahead and replaced all bearings in the case halves good or bad. I flushed the oil cooler and lines with brake cleaner and water and haven't had a problem in years. The brass is much softer than the other metals it will be a golden film in the oil. If you strain the oil through a coffee filter, or put a light behind it while pouring, you'll see it sparkle as the oil flows. Seems likely its either a bearing you didn't check and ran dry again(you shouldn't have any metal shavings if so) -OR- you caught the crank bearing problem in time to save the motor but the HR bearings you used to replace them with have already failed, putting the machine back into the condition it was in when the OEM crank bearings failed(if that is what was in there). Unfortunately, it looks to me like she's going to have to come out and be opened back up. I'm no expert mind you. The 04' and '05 had the more solid transmission parts as compared to the 06' and up.

 

[DENBROCO_05]

It will only take a small amount of shavings to work there way into all the bearings, into everything actually. Most will say to REPLACE the oil cooler and lines as well, do to this problem. Theory being how can you be sure you get ALL the metal out, and dreading missing some and sending the metal around the motor after rebuild upon first start. When I rebuilt, I didn't want to crack the cases again so I went ahead and replaced all bearings in the case halves good or bad. I flushed the oil cooler and lines with brake cleaner and water and haven't had a problem in years. The brass is much softer than the other metals it will be a golden film in the oil. If you strain the oil through a coffee filter, or put a light behind it while pouring, you'll see it sparkle as the oil flows. Seems likely its either a bearing you didn't check and ran dry again(you shouldn't have any metal shavings if so) -OR- you caught the crank bearing problem in time to save the motor but the HR bearings you used to replace them with have already failed, putting the machine back into the condition it was in when the OEM crank bearings failed(if that is what was in there). Unfortunately, it looks to me like she's going to have to come out and be opened back up. I'm no expert mind you. The 04' and '05 had the more solid transmission parts as compared to the 06' and up.

Okay im gonna get the transmission bearings ordered up as well as countershaft, water pump and clutch bearings. shippings gonna be an estimated 2 weeks but ill tear it down one last time. I just use diesel for any and every motor I've rebuilt, cleans up everything and leaves a nice lubricating film behind.... not to mention its cheaper than filling a bowl with brake clean lol. I'll report back with what I find

 

[[email protected]]

Okay im gonna get the transmission bearings ordered up as well as countershaft, water pump and clutch bearings. shippings gonna be an estimated 2 weeks but ill tear it down one last time. I just use diesel for any and every motor I've rebuilt, cleans up everything and leaves a nice lubricating film behind.... not to mention its cheaper than filling a bowl with brake clean lol. I'll report back with what I find

Doing that should give you some peace of mind.I did use HR's other bearing kits and have not seen any failure in them.
I just used the brake cleaner to flush the oil cooler and lines, I'm sure diesel will work, most of use are running rotella oil anyway.
Before you tear it apart check the oil coming out for metal.
Have you taken the transmission apart before in bikes? If you have then it'll be familiar and continue. However, if your like me, and until my rebuild never saw the inside of a ATV or motorcycle transmission, then I have some assembly diagrams from different perspectives that I've attached, they helped me tremendously when it came time to inspect and assemble the transmission. These are for my 04' so if you have an 06' and up they are not the same.

 

[DENBROCO_05]

This is going to be on my 05 and I have been through the trans before but the diagrams are smarter than me and nice to have around when your unsure of the small stuff. The orders a few weeks out but the bikes torn down and I am not seeing any metal so that’s a plus. I have this feeling I shought replace the clutch throw out bearing as well as that bearing that the clutch basket rides on just incase.

 

[hoser]

It’s funny that you bring this up, I have this issue right now on a machine. I rebuilt the motor the beginning of this year and it’s the first time I’ve ever heard a wine like that. Mine is only in gear when you are moving. In neutral or even in gear with the clutch pulled in there is no noise. I have ridden the quad a lot and haven’t had any issues or metal flakes. Just that weird whining noise that sounds exactly like what you are describing.

 

[[email protected]]

This is going to be on my 05 and I have been through the trans before but the diagrams are smarter than me and nice to have around when your unsure of the small stuff. The orders a few weeks out but the bikes torn down and I am not seeing any metal so that’s a plus. I have this feeling I shought replace the clutch throw out bearing as well as that bearing that the clutch basket rides on just incase.

Like I said, I went ahead and replaced ALL the bearings in the case halves when my crank went. I like learning things, and I did, but not really wanting to tear it all apart again gave me peace of mind.
Perhaps you already know this trick, but I was about to ruin one of my case halves trying to get the main-shaft bearing out of the case and felt I would have fucked up both sides(didn't have the right puller for that position) If I continued, so I read on here to just throw the case halves in the oven, I cant remember the temp, but it was just below were the aluminum starts to soften. Anyway after getting the cases to temp all I had to do was turn them over and all the bearings just dropped out, nice. Trick was to have all the new bearings pre greased and in the freezer ready for install when the cases are still hot. Mine dropped right in, making me a little skeptical, but once the cases cooled and the bearings warmed against each other, they LOCKED in there. I did put a little special loc-tite for oiled bearings installations I think it was, it was green, on the crank bearing housings just for xtra grab. If you replace all the bearings and you still have the whine then its not a bearing problem lol. IDK

 

[DENBROCO_05]

It’s funny that you bring this up, I have this issue right now on a machine. I rebuilt the motor the beginning of this year and it’s the first time I’ve ever heard a wine like that. Mine is only in gear when you are moving. In neutral or even in gear with the clutch pulled in there is no noise. I have ridden the quad a lot and haven’t had any issues or metal flakes. Just that weird whining noise that sounds exactly like what you are describing.

Isn’t it amazing how a small noise can drive you crazy. This’ll be the third time I’ll be in the bottom end chasing a small squeal that clearly isn’t presenting itself. The engines tore down and all my parts arrived. I’ll let you guys know when I fire the bike back up. Thanks again

 

[hoser]

Yeah them weird noises can drive ya nuts! To me it doesn’t really sound like a bad thing necessarily, so I haven’t chased it down. I used all new bearings throughout when I rebuilt the motor, so I really don’t feel like it’s a bearing issue, everything turned smooth as silk after I assembled the case halves. It’s the quad that I drove the most last Year and it hasn’t missed a beat or given me any issues, so as of now I just plan on running it. Let us know what you find though.

 

[DENBROCO_05]

Okay so....... a total rebuild later and that annoying whine is still there however I did not replace ONE bearing in the right case meaning that’s likely the culprit! my bike is an 05 and I don’t know if they even sell the bearing but if anyone knows what it is and where I can get it let me know and we will go from there. It’s the one needle bearing behind this gear that’s smack dab in the center of this circle

 

[[email protected]]

This one?

 

[DENBROCO_05]

This one?
View attachment 151990

Yessir that’s it! Thank you I’ll get that sucker ordered up and see if we can put this whine to an end

 

[[email protected]]

Yessir that’s it! Thank you I’ll get that sucker ordered up and see if we can put this whine to an end

Well I hope that solves it. Rocky Mountain ATV has good free schematics, if you'd like to know where I found the picture and part verification.

 

[[email protected]]

Well I hope that solves it. Rocky Mountain ATV has good free schematics, if you'd like to know where I found the picture and part verification.

I think that ones hard to find because when you purchase the case half that bearings already installed, at least the cases I've purchased had them installed. Just a thought.

 

[CJM]

worst case, remove the bearing and find a bearing supply and give them the specs and or ID number (if it has one) and they should be able to get it

 

[[email protected]]

Any luck Elway?

 

[DENBROCO_05]

Well got the bearing in and still as always.... she’s whining. So at this point I feel like I have ruled out everything I could to make sure the bike doesn’t fail on me. But if it ever does and I pinpoint the cause you can bet I’ll contact you! Thank you guys for the help I’d rather not tear apart an engine that isn’t showing any problems! I do have one question tho. The oil pump only circulates oil to the left half on the engine correct?

 

[[email protected]]

Well got the bearing in and still as always.... she’s whining. So at this point I feel like I have ruled out everything I could to make sure the bike doesn’t fail on me. But if it ever does and I pinpoint the cause you can bet I’ll contact you! Thank you guys for the help I’d rather not tear apart an engine that isn’t showing any problems! I do have one question tho. The oil pump only circulates oil to the left half on the engine correct?

Yes and separated by a reed valve.