Yz125 wont start

[dirtbikerida63]

hello, I just bought a 2003 yz125 the other day. I made the transition from 4 four strokew to two stroke. I can get the bike to start and run fine if i roll it and pop the clutch, but when i kick start it, it doesnt want to start. I dont know if its something wrong with the bike or if its me having trouble from starting four strokes with the long kick to the two strokes with the really short kick.

 

[YZracer021]

first check your plug and see what it looks like, then make sure you have compression.

 

[dirtbikerida63]

ill try checking the plug tomorrow, its getting to late here. Would it be the piston though, cause i can get it going fine if i roll it and pop the clutch.

 

[AwfulSmokey]

Are you using the choke when kicking it? Are you giving it some gas? I give mine like 1/8th throttle when kicking it.

 

[dirtbikerida63]

i do use the choke when i start it, the guy i bought the bike from told me not to give it gas when i start it cause it will foul the plug. tomorrow i am going to check the plug. When i do that, i should take it out and hold it next to something metal on the bike correct. If it sparks its good and if it doesnt i need to get a new one

 

[P0PWAR]

I have the exact same bike.

I usually turn on the choke and kick it once while giving it gas then kick it usually twice without using the gas, and it will usually start right up. But yeah it's probably your plug.

 

[dirtbikerida63]

i just replaced the plug on it and it still wont start. I hope its not the piston cause i just bought the other day from a guy and started for him in 2 kicks

 

[Coop]

Would it be the piston though, cause i can get it going fine if i roll it and pop the clutch.

Unfortunately a common side affect of worn rings (low compression), is having to push start a bike. Do you have access to a compression tester?

I am not saying that is it. But it is a definitely possibility. Check the air filter to make sure it isn't plugged or blocked off by a critter nest. It is obviously getting spark and fuel if it will run when push started. How does it run once it is running?

 

[dirtbikerida63]

i dont have a compression tester, are they expensive?

 

[IndyMX]

It very well could just be technique.

My cousin rode my 125 all day Sunday, he had all sorts of trouble getting it started..

Yet I can just about always start it on the first or second kick.

Maybe you should ask the guy you bought it from if there is some trick that you aren't sure of.

 

[dirtbikerida63]

good new!!! i gave it full gas with the choke off and it started right up!!! before when i never gave it gas it never sounded like the engine even wanted to turn over, now i can hear it trying. Started on the second kick =-D

 

[IndyMX]

I'd say that means your pilot is way too rich...

You need to rejet.

When you use the "choke" on that bike, it richens the pilot. When you open the throttle, you are only letting more AIR thru.

So, you leaned the hell out of the mixture when trying to start and it started.

Open the carb, find out what's in there and drop the pilot a couple sizes. Then check it again.