Whining Sound from Bike

[Milan]

Can anyone help me troubleshoot this whining noise?
Bearings?

https://www.dropbox.com/s/nd0bywwl1qfmcz0/20220807_140853.mp4?dl=0

https://www.dropbox.com/s/nn1foasaiu93g90/20220807_140958.mp4?dl=0

Bike runs smooth thru all gears


M

[m in sc]

bearing? side note.. triples have straight cut primary gears. check your trans fluid.

[Milan]

I am a novice at these bike.

I had just filed up the tranny with same fluid as in the RD's.

M

[m in sc]

ok.

like said, might be a bearing. if the trans fluid is fine, my guess would be that, if a bearing, the one behind the clutch if its not going away w correct fluid level. Had an H1 that grenaded one on the way into work one day, and I could hear the teeth backlash get off and howl when it was moving around and whine like that, made way more of a racket though.  could be 1st gear. who knows.

[1976RD400C]

Is that noise happening only as the clutch is slipping as you take off and then goes away once the clutch is engaged? 

[m in sc]

put it on the center stand, fire the bike up, put it in gear and listen to it. helps to pull the trans fill cap as well. *may spray fluid though. might be more clear as to where its coming from. 

[Milan]

The noise happens in all gears.
Clutch fully engaged.
Gets less as the rpm's go over 3500.

So you hear it on take-off, and then when riding.
Kinda sounds like the clutch area.

I have a parts list so I will look for the bearing Mark mentioned.

M

[Hawaii-Mike]

Based on what Mark is saying, pulling the engine and taking it apart sounds prudent.

[m in sc]

id start with the clutch cover, pull the clutch (basket as well) and check the shaft for play. look at primary gears for excessive wear.

[Milan]

So I talked to the seller in the UK.
He gave me the number to his Mechanic there = David Howard.

David mentioned he was a partner with Rick Brett, the Kaw guy in Michigan

Anyway, he said the whine was quite common.
Replace the primary gear & clutch hub gear.

He had some NOS parts.
sent them to me.
Put them on, and sorted the clutch & oil pump gear stuff out = other posts.

No more whine from that area, sounds good.

Put in 75W-90 gear oil.
I can here the gears a little, so I am going to try the 75W-140 gear oil.

Or, Maybe something in between.

M

[Kawtriplefreak]

I run Lucas80/90 in all my two strokes. 75/140 is quite thick. Some gear whine that varies in pitch during clutch actuation  is normal in a triple gearbox.

[paul1478]

It could be my wife. She is always whining when my bikes.

[m in sc]

well triples run straight cut gears so they are always going to whine somewhat. especially will be noticeable on a quiet stock bike.

you should hear my t500 it howls pretty good and its fine
.. stick w the 75 weight, that's way thicker than the manual recommends anyway.