Tag Archives: WR-125 Engine rebuild

Removing lower timing gear on YZF-R125 attempt #2 – success!

This is the second attempt at removing the lower timing gear and the captive bearing on the crankshaft of my spare “B-motor”, which I’m trying to build up for my bike.

Idk if this is how it’s supposed to be done but I’m working with what I’ve got.

Whether this turns out to be a good approach or not long term remains to be seen but for now let’s see how far we get with it…

How not to remove lower timing gear on YZF-R125

This is the first of my “descent into madness” series of videos where I’m trying to rebuild this spare R125 engine.

I bought the engine as broken and when I took the cylinder off the bearing surface of the little end was damaged, which means the crank needs to be pressed apart to fit a new connecting rod.

So basically I have to take the entire engine completely apart just to get to this one dumb piece to replace it.

The videos are out of sequence but I have such a backlog and there was going to be a plan and it all went to crap. Every expert I was hoping to get to help me with this basically just disappeared or didn’t follow through, so I’ve finally resolved to buying the kit and figuring out how to do it myself.

Even though the engine in my bike has issues (from when I messed up a couple of years ago), despite that it’s done another 5k on the 180 cylinder (even wiht the timing chain issues) and I have not gone easy on it 😉

I’ve had a few people asking me to rebuild engines and do upgrades etc which is very cool, so it seems like it’ll be worth learning how to do it.

Hopefully this all ends with an engine dyno and building mad engines as was always the dream/plan 🙂 I’ve added this video to a new playlist for the B-motor rebuild so I can add all the other videos to it as I work through them. Thanks for watching and thanks to SXparts.com for sourcing hard-to-find components like the lower timing gear.


UPDATE: I said in the video (at 2:08) the lower timing gear wasn’t available, well it turns out i was wrong on that and you can get it here. Thanks to A for the link 🙂 https://www.cmsnl.com/products/sprock…

#YZFR125 #R125Life #bikelife #bikewife