All 2st Noise when clutch lever is not pulled in while idling.

Both my CR 125 and the WR 300 make a very noticeable whirring noise while idling when the clutch lever is released in neutral. They've done this since new and sometimes it's louder than other times. I've chalked it up as normal since it hasn't presented a problem (yet). It is also noticeable while riding at lugging speed (louder on the 300 than the 125 while riding).

Do others have this noise? Any cause for concern?

I've switched the tranny oil on the 125 from a 10W40 4T oil to a Redline 80W gear oil and it seems to have helped quiet things down. May try the same with the 300 soon.

No biggie, just wondering what others may have to say.

Both of my KTM 300s do that,...it's kind of a known KTM thing.
My WR300 sorta does it too, but not nearly as noticably as the KTMs.

I always figured it was just slack in the clutch plates/basket assembly when relaxed,...and it goes away when you pull the lever and compress the springs. Yeah, I've noticed that heavier gear oil dampens it down too. I use Bel-Ray Gear Saver in the 85W vis.

FWIW, my '03 KTM 300EXC has done it since day one and I've never had the clutch cover off it.

Most of the bikes I've owned have done that to some extent, and heavy oil usually lessens it. My 510 might be the loudest bike I've ever had though. I haven't split the cases yet, but I've been everywhere else and everything seems fine. Just one of those things I guess.

My 510 did it as well as all of our Triumph street bikes so far. Seems to be a normal occurrence after breaking them in......

My sportscar does it too.. along with my, pavement only, road bike..

It's normal. I have heard it is the way the gears are cut. If they are square they make noise, if they are angled they are quieter.

It is totally natural that the mechanical sound is much louder, because with the clutch engaged, the power impulses of the engine are directly coupled to all the loose unloaded gears in the transmission.
CLANK CLANK CLUNK TICKA TICKA. Sound familiar?

I would say these are normal noises for straight cut gears.....helical gears are much quieter and stronger...but are often not used for reasons of cost and the fact that they produce side thrust which would need to be controlled...

some other noises such as gear rattle...will also be heard when releasing the clutch in neutral..and the mainshaft starts to turn...also very normal

its all good

Thanks guys. I felt like all was fine since nothing has jettisoned itself out of the crankcase while at WOT, but sometimes it's nice to get some reassurance from the crowd.