Yz125 Major problem!!

[Moto man26]

Hey guys,
Here is my story of what happened when I was out riding yesterday.... I was trail riding, and every was great, and then my dad noticed that the chain on my bike was pretty slack, so we went back to the truck and tighten the adjustments on the end of the swing arm. I then started to go riding again and then after like 15-20 minutes of riding, the bike just cuts out as if it stalled and the bike braked pretty quickly. I thought that it must of had a branch stuck in my wheel or something, so I just kick started my bike up with no problem, and when I put in first gear to take off, the bike stalled as if something was holding it back from going forward. I got off of my bike to see what was going on and I noticed that my chain came off of my bike and got wrapped around my front sprocket and now it is jammed up front in one chunk( but the chain did not snap only part of it got wrapped in the chunk). I tried to get the chain unjammed by pulling on it but no luck. My question is, could this have done any damage to my transmission(When it locked up I was only in first gear)?
I would also need help on how to remove my front sprocket on my yz125. There is a nut that keeps it tightened to the shaft, but if I turn the the nut, the sprocket is going to turn. So my question is , do I lock the sprocket by putting the bike in gear or do I have to do it when there is a chain on the sprocket.... Any help will be appreciated!! Thanks alot!

[Malcolmv8]

Sorry to hear about your chain wrap up issue. That sucks.
I have the same question about the front sprocket removal. I just got my replacement front sprocket in the mail today and am also curious as the the best method of getting that nut off. Well I guess an air impact gun would do it but then how do you tighten it back on?

[YZ125motoracer]

put it in 1st gear and tighten it up good

[2000 cr250rider]

to get your front sprocket off put it in gear then put on the right size socket and rachet. take a hammer and hit it really fast so it will break free. it is possible to be revearse threads. mine wasnt but it is possible. maybe somone can tell you if not.

[Moto man26]

Hey guys thanks alot for the help , but I think that there is something wrong with the adjustments on the end of my swing arm ( the ones to adjust the chain tension etc.) I'm saying that because once when I went riding and got back home, I noticed that my chain was really tight, so I re-adjusted the adjustments on the swing arm and every thing was fine after. And then the other day after riding for 15-20min it was really loose.
What could be the problem???

Any help will be appreciated!!

[YZalltheway]

make sure that you are tightening up your rear axle bolt when your done adjusting your chain

[Florida 393]

Check the adjuster bolt's lock nut for being tight, check the adjustment index marks by also measuring both sides of the axle from reference points to be sure the wheel is running true, not canted and when you torque the axle nut down use a torque wrench and set it to the factory recommended torque. Hope these help.

Bill