CR125 won't kick start but will push start?

[ktm84mxc]

As for the right plug rock down to your local bike shop & ask to see the NGK booklet with there plug fitment guide it will list the suitable plugs for your bike.
If it was my bike I'd chuck a piston & rings in it , and get the conrod play measured while itz apart.
Also wen waz the muffler repacked as this can cause a flat feeling with the power delivery, you can also de-coke the expansion chamber. A lot of little things add up to make a larger problem.

[mad_max]

I put a new plug in it out of another bike, started 1st kick, ran well, was only running for 30 seconds (not exaggerating) up the drive, hit the kill switch, went to start again and nothing. Put plug back in bike it came from and nothing there either. So it buggering plugs in a matter of seconds. Must be something more wrong that just needing a rebuild. It didn't stop itself, ran mint. that's the one thing that's most depressing, it runs mint and doesn't stop unless I stop it

I don't want to go spending a heap to rebuild something that doesn't go properly anyway so wanna get this sorted

Got told it could be magneto??? Any thoughts on that?

[CRF119]

What oil ratio are you running? Also use 98 gas

[cheese]

I had a bike that was like that, it was a leaking crank seal fouling the shit out of the plugs. Spray your like with CRC and hit it with a wire brush and see if it goes again. But seriously, put a new piston in it.

[mad_max]

Hi, I just started to take apart, took sub frame, tank, plastics etc off. Then I took the expansion chamber off, filled with antifreeze. I dont have clue how it would get there but Im pretty sure its not good. took the head off and its all in the cylinder. I am not very experienced with motors so dont know what it is but I know one of you will know straight away. Hopefully something not too expensive

Thanks for any help

[noobi]

Coolant can only get into the cylinder through the head or base gaskets, and judging by "full of antifreeze", the gaskets are well past their use by date. Replace the top end, including gaskets and o rings.

[mad_max]

Yip, just found that the head gasket was actually the wrong gasket. I think it was off a different year or something but definitely was wrong. Cylinder and everything else looks good so will rebuild and hope like hell it was just the gasket

[barty5]

Hi, I just started to take apart, took sub frame, tank, plastics etc off. Then I took the expansion chamber off, filled with antifreeze. I dont have clue how it would get there but Im pretty sure its not good. took the head off and its all in the cylinder. I am not very experienced with motors so dont know what it is but I know one of you will know straight away. Hopefully something not too expensive

Thanks for any help

blown head gasket hence hard to start cause your plug is wet while your push starting it is turning over fast enough to clear the water/coolant and then starts. hopefully the head is not damaged from the heat as it must have been low on water given it was using it.

[mad_max]

Yea, it was low on water and I put some more in it assuming it had leaked somewhere when I was riding because the pipes aren't the best, when it started with a new plug it seem to disappear with no visible leakages, turns out it had made itself at home in the bottom and and expansion chamber.

[CRF119]

Some 2001 CR125 bikes require 2 x head gas kits or they keep blowing them. My mate blew 2 before he found this out.

He started his one day and coated the house in black oil and water