CR125 With Odd Engine Noise

You guys are simply genius on here. I got another one for you to figure out. I have a 1994 CR125 that i recently rebuilt i.e. bearings in bottom end and new top end. It starts perfectly on first kick everytime. revs perfect in neutral. When i shift to first and clutch still pulled, sounds excellent. BUT, when i start to release the clutch and barely start moving, there is a high pitched "whirring" sound from the engine. It gets higher pitched and louder with the throttle movement. It is also in second gear. Third fear and so on just drown out the sound! ANY help would be much appreciated. Thanks!

I dont recall it doing that before the top end but the shop gave it a once over and didnt find anything

any help at all would be much appreciated