Cr125 2 stroke help !!!!

because its a 250. Mine does it too. Try starting a 500 2t talk about snapping your leg in half.

 

yep yep, my 250 also does it!

 

Did you ever get it running?

 

Nope, I changed the oil/gas, tried to bump start and nothing. Went to AutoZone to get a starter fluid and nothing. All i hear is the piston going up and down. FML

 

I bet either the rings are gone or theres a hole in the piston. Honestly I would pass on it because it was obviously not maintained properly.

 

What you mean by "pass on it"

 

Not buy it.

 

he already bought it, and its probably going to need a rebuild

 

x2

 

Oh.

well it looks like its time to pull the cylinder off and see whats wrong.

 

just tear the damn thing apart and go through EVERYTHING. 2 strokes are easy to tear down and re-build.

 

Yeah, im taking it to some guy to check it out this week.

Free estimate

 

sounds good if its free, but don't pay someone to work on that bike. Its really easy and fun too.

 

yeah, especially if im keeping so i can learn But my kx has been so good to me

 

I betcha there is a nickle sized hole in the center of the piston. sucks,,but a easy fix if so. gasket set, piston, cylinder hone or slight bore. a couple hundy total(maybe less), and it should be up and running then.

The trick is why did it meltdown if it did,,this needs to be found out or at least investigated also,,or you will be right back to square one.

Did your cousin mess with the jetting in the carb??. if he did mess with it, it needs to be reset to the original factory richness, to break in the piston properly again. That piston, heat expands faster than the cylinder sleeve, and it need to be cooled and lubed right as it wears in again.

 

My bike is in the shop right now..fork seals and brakes

 

i have an 01 cr125. i love it. once you get it running right, maintain it properly and you will be good to go

 

I've raced/ ridden damn near every single 125 out there. I've blown up many of 125's in my day. When they go, you know. There is quite a bit of a difference between low compression and no compression. What does the air filter look like? If you can turn it over with your hand and there is no resistance, then it has no compression. On a 125, usually means a broken ring. If you feel the kick starter step, then it has low compression and piston and ring should solve your problem.

If there is a hole in the piston, someone was getting some detonation for a while. This would be the result of running 87 octane in your 125. This is not very likely but don't put too much faith in humanity. On a 125 the chances are pretty good it will run like total shit before it burns a hole in the piston and said cousin should know.

I think your cousin was probably someone who mixed oil correctly and rode that bike for a while but never did a ring job at the least.

Worse case, you need a piston, ring, and cylinder.

Best case, it needs a piston and ring.

In the whole grand scheme of things, you are getting a pretty good deal on it.

 

I was about to say that ^ i raced a cr125 for years, never had a problem with it, just change the top end, mix your gas right and clean the air filter you should be alright.

 

update.. got pictures of the piston and cylinder.