Engine Failure: Camshaft and Piston damage - Rebuild in progress

Thanks for input Toby
Currently waiting for the mechanic to get back to me.
Seems to be internal issue as the new sprocket is doing the same thing.

Told them to open her up.

Update:
Mechanic says, "main bed on crankshaft root cause, bearing failed, it disintegrated, jammed the engine, jammed gears, Some gears got damaged."
Good news: A couple of the parts can be saved and reused in the engine.
- Awaiting a quote, hoping I do not need a whole new crankshaft as I see they are over 300usd.

@Tamir Have you ever had a bearing fail on the crankshaft causing similar issues?

UPDATE:
Crankshaft and Piston rebuild kit is required.
With all the needed gaskets.
Local mechanic asking 1500usd to repair.

Sourcing parts from an alternative supplier to see if I can save costs.

It is a dark time, this cbr is costing me the same price as what I paid now.
But in all honesty, it's saves so much fuel and drives so **** good I have to restore it.

@Tamir unfortunately I did not notice any engine noise, but my hearing is not good.
The mechanic noted that the engine noise is odd on the picture of quote I attached about fork seals that were done.

Thanks for the condolences and advice.
Went with the risky route and ordered the parts from abroad and importing them Myself.

In South Africa there is a massive boom going on with motorcycles due to grocery delivery becoming a very big job market.
The odds of finding a 250cc engine is close to nothing, the delivery guys all buy them the second they are online.

Another point is this bike saves me roughly R2000 in fuel a month, so everyday I drive it, it saves me money.

Searched the bike market and could not find any other bikes below R70k.

I'm rebuilding her, and hoping to get another 60k km done on her.

Teen Punch said:

1. Could the damage caused to the black plastic be related to the issues I am facing?
(The mechanic claims he did not cause that damage, but I have photos of before I took in the bike in and after, as they damaged my front break fluid glass thing in December).

Click to expand...

Hi there, this has been concluded to be completely unrelated.
The engine simply reached end of life due to excessive use, 66k km done, no idea how many owners the bike had.

Thanks for the input @TheoR
The filter seems to have been installed correctly as seen in one of the images.
Also cross checked it the other day with Tamir's guide.

The left side of the bike got dropped that's for sure, there is a big round thing on the left side casing that's supposed to be silver, but it's black, so they resprayed for sure.

Previous owner messed up the wiring, had led strip inside and no working headlight!

The air filter cover was removed off the bike when I got it, that little black lid.
Ordered and installed one about 3000km ago, motorcycle also ran in cold dry climate it's whole life, then moved to the coastal area and used in 30-40degrees.