125-200cc WRE 125 2000 rattle after engine rebuild

Hi guys.. I have rebuilt WRE 125 2000 of my girlfriend... All bearings and seals are new... new piston, new crank set... When I fire it up it rattles at idle, but no rattle at higher RPM... I have noticed, that one or two of springs in balancing shaft wheel are broken.. Could this be the cause of idle rattle?? What else could cause rattle just at idle?? Thanks a lot

nobody can help??

This is kind of a dual sport or entry level street legal in europe bike isn't it? Is there a powervalve and governor?

Replace the broken small springs and most important things ensure all 3 balancing markings are properly aligned.

Does the rattle disapear with the clutch pulled in?
And yes replace springs and make sure its aligned!

So... all marks aligned... spings replaced.. still rattling at idle.. if I just touch the gas, the rattle disappears...

Not the kick start hitting your exhaust, any way you can narrow down the area its coming from?
My bike sounds like it's going to grenade but after hearing several 360's I put it down to piston noise.

not kick start.. it is coming from somewhere near crankshaff, but crankshaft is new... everything is fine.. bike is really powerfull, just that rattle

I have just wathed this video and there is rattle too at idle... the same on mine... maybe it is normal

Maybe you're nut on the crankshaft came loose. or the nut on the clutch basket.

Well the engine isn't under a bonnet so any noise it makes is open to be heard, I put that rattle in the vid down to gearbox chatter as the gears mesh and catch up with each other it will go away under load.

so nothing to be worry about??

I would record it in your phone and ride it for a while see if it gets worse, of there's plenty of power and the noise is the same after 10 hours then it's normal.

Who did the engine work as stated could be something left loose. But two strokes are noisy.

I have ridden it for few hours without change... engine work done be me... tripple checked everything.. nothing loose

So today bearing on crank crashed... it was koyo.. brand new... 300km on it.. how to get it from crank??

Brand new?!? That's got to be a fake, where did you get the bearings from?
Strip the engine down and either use a bearing puller or go very gently with a grinder on the knackered race.

Dam that's not good.

P.s. I always buy bearings from a reputable supplier not Off eBay.

Were the oil lube holes clear when you re-assembled

It was not bearing on crank.. but main bearing on crankshaft..

You mean big end?
Well that's a new con rod required.
Didn't know koyo made big end bearings.

New big end bearings can go wrong just after a few hours if: they are sold as Hotrods/Wiseco parts, if they are running with not enough side to side play or if the engine cases are not lined up properly.
I had several Hotrod Crank failures on different bikes,brands and users- DONT BUY THEM!
I also had a Bigend Failure because someone pressed the crank and did not check the side to side play.... big mistake!