You are the most technically involved dirt bike repair youtuber I have found.  Your experience and knowledge shows.  Love your ingenuity to improve little things.  Thank you for your videos.

On 2-strokes - which are mostly ball bearing left and right - you are supposed to center the crankshaft with hammer taps to prevent side load. With heating  up during normal operation side load may occur but I have also read of some mechanics changing the LC4 (4-Stroke 654 cc) to Ball bearings because the oem roller bearings on both sides can not withstand the load of a crankshaft which is unevenly stressed because of sagging and twisting forces.

Chuck is a national treasure and a real master technician
Coming from a fellow tech in the hd world

Mr.Chuck im impressed and inspired by your quality and knowledge of rebuilding them powersports. Thanks for sharing your knowledge with us in such great detail!

Good job. KTM also used a ball bearing on the 950 LC8's balancer shaft. Later, for the 990 they changed to a roller bearing. More expensive, but easier to install correctly and without damaging the bearing.

KTM have used the NJ series bearing on the flywheel side since approx 2001- cant believe the other 2 stroke makers havent done the same ! they actually use a bigger NJ207 on the 250/300, the NJ206 is for the KTM125/200's

Great Vid !!! I have no interest in rebuilding a bottom end. But you explain things so well I enjoyed watching and learning the process.

Nice video, like always 👌🏼 recently i rebuild my TM EN300 2015 engine. This model had two roller bearings, really nice. The hole engineering on this engine looks good, with lubrication holes on the clutch design etc.

Excellent information, I hope not to have to use it. I swapped my spring clutch for the bellville washer style (for a lighter clutch pull) , I liked the ease of retrofitting upgrades with Beta.

This was awesome. Saving this vid for future beta maintenance. Thanks Chuck!

Great video Chuck..

ANOTHER great vid , thanks Chuck!

Nice work on the bearings.
My thoughts on your punch --> Grind the mushroomed edges off, I know two people who have lost eyes to those breaking off when being struck with a hammer. One on an oil rig and one in a shop, both times it was a punch just like yours.

Great video thanks for sharing.

Nj206 life!

Interesting, I was curious about doing something like this to a much older bike during my first rebuild this year but I figured if the engine with original bearings lasted 40 years I probably shouldn't start changing things. After pressing the case halves together I gave the crank a few smacks with a rubber mallet and it seemed to find a happy place as it loosened up considerably and became extremely smooth to rotate.

Thanks a bunch my 23 300 race edition has crossed over 100 hours of perfectness, but it could con out tomorrow laugh out loud yes give us the third video showing how to put the case back together☝️👌

👍👍

Il y a aussi d'autres méthodes douces elle aussi.

Wil this bearing nj206ecp.will work on my 21 xtrainer.?