hey there!

step by step im building the bike and i tried to see if the starter would work. 
now when i push the start button a weird buzzing sound appears, anyone know what this might be? 

thanks in advance, here a video to clarify. 

https://youtu.be/84hOf5lDad4

Low voltage on the battery, charge it first, or jumpstart with a car battery.

If the buzzing sound is kind of lasting wizzz, like a turning electrical motor, it is clearly your starter free wheel which is gummed and does not "bite".

If you can avoid reaching it for cleaning or changing it, take the chance

I am new here and have obviously not read all the subjects, though I assume that this slipping free wheel frequent problem was met already.

Here in France we can be somewhat barbarian    In a forum I follow since 15 years the suggested and generally working trick is to remove one third of the engine oil, i.e. approx 1.2 litres, and replace it by the same quantity of diesel (the one you put in trucks or tractors tanks). Start the engine as you can, generally by pushing the bike just after having pressed the start button, to put the fuel circuit under pressure, then run the bike for about 15 minutes /kilometers without exceeding 3000 rpm. Once done, drain oil completely and rince by operating the engine with a cheap oil for a few minutes. Then drain again, change the oil filter, and refill with good quality diesel motor oil, grade 15w40 or so. Never use gasoline oil again.

This side of Europe many Ks work on diesel oil, which is detergent, hence its interest for keeping the free wheel operational. Do not underestimate diesel oils, they are subjected to much more stress than the gasoline oils.

One emergency way to eventually make the free wheel bite when it does not want is to operate it in the wrong way: instead of making the internal side drive the outside one, try to let the outside part drive the internal one. For that, engage one gear, for example the 3drd, and pull the bike backwards. That gives the engine an impulse in the wrong direction (the distribution chain tensioner can very well stand it) which can unlock the free wheel. No guarantee of result but worth trying

I let all of my oil go, but lest the filter alone.
Then fill it up with diesel, run for 5 minures, drain and replaced the filter.
Then add some new oil and Slick 50 to the max, start it, and check the level.
Loads of crap came out with the diesel.
Running smoother now after 200 km.

Poupy wrote:. . . kind of lasting wizzz, . . .

That's why I quit drinking Bud Light—that and the taste of it.

Regardless, it's difficult to mistake a bilabial stop for a labio-velar approximant.