cr125 help please

[JOHNSTON]

hi there, i currently have a cr125 2001, now the problem is the bike will run for 15 mins then bog down and die, the plug is black and oily when i take it out and if a fit a new one it will run again. i beleive it is the jetting but just wondered if any only else had any suggestions.

the bike was fitted with a vhm head when i bought it but it hadn't been fitted properly by previous owner and crack so a standard head and gasket are on now too.

so far i has a whole new ignition system, everything rewound and changed, new piston ring,

bike will be going into the shop next month but wondered if anyone else had any ideas a could try

thanks johnston

[Hooli]

if you've changed the head type have you changed back to the standard jetting? i get it was re-jetted to suit the different head.

[bimsb6]

what 2 stroke oil are you using ? are you mixing it too rich ?

[JOHNSTON]

was using silkolene comp to pre-mix, sure am mixing it 25-1, bike hasn't been run for a year so don't know how easy it will satrt.

tanks drained and the carb is cleaned and fitted, will be putting a 1 litre in just to get the bike running before a take it to the garage

[podman]

When it bogs down and dies will it re start and still run badly or will it not restart at all until you have changed the plug?

[JOHNSTON]

podman said:

When it bogs down and dies will it re start and still run badly or will it not restart at all until you have changed the plug?

won't start at all, not even bumping it down massive bings works

[podman]

Id go for a coil breaking down then...especially if it starts when the bike has cooled right down

[Carl-H]

Fuel breather. Next time it does it take the fuels cap of and see if there was any pressure.