KX Guru Racing

So, we had a customer come in with a lot of engine noise...
Sounded really bad.
Once we got the top end off we discovered that the piston and rod were trashed...
The customer has a tight budget so we decided that we would replace the piston with a Wossner, Millennium plating of the cylinder, Wossner rod kit, full Cometic gasket kit, counter shaft and trans bearings, timing chain and guides.
One of the things about the earlier YZ450F's is all the lower end engine noise that you just can't seem to get rid of.
With gear clearance like this it's no wonder..

https://www.youtube.com/watch?v=5VENjuK ... e=youtu.be

While he will have a solid and reliable engine when we are done we would like to replace nearly everything in the engine.
Unfortunately the budget forces us to ignore a lot we would like to replace..

Here's some more tear down pics for your enjoyment

Here is something you NEVER want to see in your motor.... SAND

After a bit of clean up..

Before
After

After carefully sanding all the sharp edges a little clean up is in order..
The last thing you want to do is put a piston into a cylinder with sharp edges as it will scrape the oil off the cylinder
Millennium sure does a nice job plating and honing.

Checking piston to cylinder clearance
Looks great!

Doing a test before assembly to make sure there are no issues..

A bit more progress today...