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jaaaaaaaaaaaaaaaaaaaaaaack Started a new thread Blown up cr125 bottom end question
10/28/2020 9:17am I have a 2007 cr125 that I just blew the piston up on. I had been riding it pretty consistently for a couple months without any problems and it seemed to go out of nowhere. And when I took it apart i found that the piston was installed the wrong direction, so the ring caught on the exhaust port and...
This forum thread has 21 replies.
jaaaaaaaaaaaaaaaaaaaaaaack Added a reply to Blown up cr125 bottom end question
10/28/2020 9:17am Thanks for all the advice, since I cant be sure that the bottom end is fine I'm gonna hold on to the bike for another year at least and just rebuild and clean up the whole bike. It's about winter time her in CO anyway so good time to tear it apart.
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walent215 Liked a reply to forum topic Blown up cr125 bottom end question
10/28/2020 6:50am
If there was significant amount of debris in the bottom and yes you need to split the cases but if there was a couple minor little chips or flakes that you could see and remove them I would remove them and to be doubly sure I would turn the motor upside down rotate the crank and flush it out by spraying it with some WD 40 or solvent or something of that nature.
This forum topic has 21 replies.
jaaaaaaaaaaaaaaaaaaaaaaack Added a reply to Blown up cr125 bottom end question
10/28/2020 5:51am But dont I have to split the case to see if there is metal in the bottom end? If I rotate the crank I can see down the middle of the case and I dont see anything other than a couple little dust size specs, but from what everyone else is saying it sounds like I cant actually tell what's...
jaaaaaaaaaaaaaaaaaaaaaaack Added a reply to Blown up cr125 bottom end question
10/28/2020 5:48am When I look down into the crank I can see to what I would think is the bottom of the crank case and there doesn't seem to be any metal I can see, but there are other spots in the crank case that pieces could be that I cant see unless I split the cases correct?
jaaaaaaaaaaaaaaaaaaaaaaack Added a reply to Blown up cr125 bottom end question
10/27/2020 6:35pm The reason I am really asking is because I was planning to sell the bike and get a 250. And then the piston blew. So I'm trying to save money on the rebuild if possible. I dont want to put 800 bucks in for the new cylinder and top end and bottom end just to sell it.
JMCR250 Liked a reply to forum topic Blown up cr125 bottom end question
10/27/2020 6:32pm
On a two stroke, the lower end is sealed off from your transmission, so if you're finding pieces of metal in your transmission drain plug they are coming from your transmission or clutch OR you blew a hole in the case between where the crankshaft rotates and your transmission. You have significant enough damage to the cylinder/piston/ring that you should split the cases and check the crank, crank bearings and the integrity of the cases. At the same time, maybe you'll be able to find out what is causing the metal bits on your transmission oil plug. You'll need a...
This forum topic has 21 replies.
Wolfey Liked a reply to forum topic Blown up cr125 bottom end question
10/27/2020 6:32pm
Yeah flywheel puller is one of the tools. You don’t have to have one but a crank splitter makes the job much easier. If it’s your first time doing a bottom end, you can watch some how to videos on YouTube. I know Rocky Mountain atv has some great videos on rebuilds. Good luck to ya.
This forum topic has 21 replies.
jaaaaaaaaaaaaaaaaaaaaaaack Added a reply to Blown up cr125 bottom end question
10/27/2020 6:31pm The main crank bearing seems fine, just from pulling on the crank arm. And i had it for a couple months before it blew, allot longer than I would imagine it lasting backwards.
jaaaaaaaaaaaaaaaaaaaaaaack Added a reply to Blown up cr125 bottom end question
10/27/2020 5:50pm Are there any special tools I need to do the bottom end? Theres some kinda flywheel puller/install tool correct?
jaaaaaaaaaaaaaaaaaaaaaaack Added a reply to Blown up cr125 bottom end question
10/27/2020 5:41pm Yea that seems like the proper way to do it. Thanks for the advice
jaaaaaaaaaaaaaaaaaaaaaaack Added a reply to Blown up cr125 bottom end question
10/27/2020 5:28pm At that point would it make sence to do a whole bottom end rebuild, rather than open it up and clean it and put it back together?
