Problems starting

[PeteThePom]

One other possibility, you say it starts easy if you bump start it from cold?

Does it tickover nice and smooth once the engine has warmed up?
Have you noticed any drop in the gearbox oil level?

[Sheep Dags]

Yep, starts pretty easily if jumped from cold... and yea, absolutely no problems once it gets going... smokes a lot cold but so do all 2 strokes.

.... oh and gearbox oil?? Where would i check that? :/

[PeteThePom]

Yep, starts pretty easily if jumped from cold... and yea, absolutely no problems once it gets going... smokes a lot cold but so do all 2 strokes.

.... oh and gearbox oil?? Where would i check that? :/

If I remeber correctly yours is a NS yeah?
Gearbox oil level check is on right hand crankcase, you should see what looks like a regular oil filler cap and thats where u check the level, the point I was getting at is maybe, and this is a maybe it might be that your crank seals are leaking, if they are you'd notice a loss of gearbox/primary drive oil and also that oil would smell of petrol due to contamination across the seals, but you didn't answer me on the tickover issue.....................

[JeremyW]

Talking about difficulties starting I am having trouble getting my new (well 88' but new for me) CR125 started. It has wicked compression (kicks back!) so its not that, how would I check if the plug is fouled? If so does that mean a new plug? Sometimes it will start and then have a few ticks over and die again!

Any suggestions would be good cus I want to take it out tomorrow!

[Cactuz]

Hey mate I had this issue on my GSXF400, I spent 2 monts of afternoons cleaning carbs, changing sparks, batteries the lot and found out it was something simple.
Bike needs 3 things to turn, Spark, Air and Fuel

Spark: Take out a spark plug, connect the ignition cable and hold it against the engine block and crank her over. You should have a bright blue spark (not white). Make sure u hold the cable and not the plug so u dont shock ur self. If there's a weak spark get ur self a jump start kit n increase the current

Air: Try cranking with the air filter off, if it starts then u need to change filter

Fuel: To make sure that fuel n air isn't the issue, when u pull out the spark plugs put a little bit (i mean little, like a 600ml drink bottle cap full) of fuel into each piston through the spark plug hole. If it starts or wants to start then you know that is the problem. Make sure the fuel lines dont have holes or cracks, i found the only thing wrong with my bike was that i had a very very tiny hole in the fuel vaccume tube that goes from the tank to the carby.
Or your fuel might be old, Fuel tents to turn into a jelly after 3-4 weeks of sitting still so change the tank and drain the carbs. (if u wanna know how to do this let me know).

Hope this helps bud!
Cactuz

[Cactuz]

Talking about difficulties starting I am having trouble getting my new (well 88' but new for me) CR125 started. It has wicked compression (kicks back!) so its not that, how would I check if the plug is fouled? If so does that mean a new plug? Sometimes it will start and then have a few ticks over and die again!

Any suggestions would be good cus I want to take it out tomorrow!

Read the post above. Buy your self a spark plug spanner and take them out. You can tell alot from just the plug, check the colour of the ceramic on the plug. It should be a light grey, not white (running too lean) and not black (too rich). When u pull it out check that there is metal left sticking out of the housing on the tip, if so give it a good scrub with sand paper and also do the same to the inside of the arm that comes above it. (if you fold the sand paper so u got grit on both sides you can prob do this at the same time. Check the gap between the arm and spark head and see if u can get a good spark against the cylinder head. If not, go to motomail clearence store first, they have a box of assorted spark plugs on clearence for $1 EACH!!! hope u can find the right ones there

Hope this helps
Cactuz