Dec 11, 2019 · On my 08 YZ125 the pins fell out twice. I replaced the solid pin with a roll pins and they stayed in. I would be a lot more concerned about the missing or loose pin on the top right …

Mar 11, 2013 · A few years ago I got a spare '06 YZ125 engine from a friend which had a broken case. I had a 2008 model at the time so I figured it was good for spare parts. From the looks of …

May 25, 2014 · Full motor rebuild was done about 7 hours ago. Questions- has anyone else had one of these break or heard of it happening? Would your guestimication be that piston-to-valve …

Feb 28, 2023 · Stripped down top end, 1 wrist pin clip is missing and piston has broken at clip location. 3 gouges to cylinder, bottom end is locked and I suspect the wrist pin clip has …

Jun 9, 2017 · I've heard someone that works in engine development at a major auto manufacturer say that with modern plated cylinders, coated pistons and alloy piston rings, engines are 95% …

Oct 20, 2012 · Get it up to temp and test with the stock jets. Drop to the next size down and repeat. Listen/feel for any signs of too lean. If none, drop to the 2nd size down. My guess is …

Oct 9, 2021 · I had this happen on my first yz125, replaced it, and it turned out the motor was pretty badly clapped out. I would bet your bottom end needs a rebuild and everything. Worth …

Oct 19, 2010 · Rode for 10 minutes, stopped to talk and when I went to start back up, my 2nd kick I hear a "clunk" and something hits the ground. I look to see my kickstart lever and thinking "oh …

Apr 18, 2023 · Take off the right-side Case-Cover (Super easy, just be careful when torquing down the bolts after putting the cover back on, as those fucking bolts are very easy to break. …

Jun 22, 2024 · sign the engine ran excessively hot. (lean jetting, fuel delivery issue, air leak etc.) Explain in detail how you were riding the bike when it seized, my guess is that you were 'road' …