Fouling plugs in my yz 125

By Anonymous (not verified), 6 May, 2005

Forum Topics

Hi,
I have a new 2005 yz 125 that I ride trail on and when i put a new plug in it runs good but after i stop for an hour or less it well start back and and ride for about 20ft and then "pop pop pop" It fouls when i pull the plug it is wet and dark.. ill be lucky if i can go a day without fouling one.. im 15 and live in eastern kentucky and i mix at 32:1 with yamalube 2 cycle racing oil so what do i need to do?

you might be useing the wrong

you might be useing the wrong spark plug my friend had a xl250 and he put the wrong spark plug in and the spark plug was to big and he heard a pop bang sound i a think he cracked the pistion his bike wont start

Same problem!

Hey my man!
i had a similar problem, but a 2003 KX 125, fouled abt 20 spark plugs in the first month of having my bike, they changed the coils and fly wheel. Wasnt that. then after abt 2 months of experimenting, they found it to be the spark plug cap.

Hope this helps.
Cheers

hey dude

me too i had the same problem. my dealer said i didnt need to buy jets . i fouled 5 plugs the first week, try this: 400mj, 35pj, stock needle, stock postition, and br8eg plug. i use silkolene 50 to 1 . i live at elevation of average 600 feet above sea level. you made need to lean it out in kentucky. by means of main jet. but try mine first. if anyone has anything better, please email me at dirtlovers5p@aol.com . thanks and have a great day!!! oh and good luck.

hey i have the same bike just

hey i have the same bike just adjust the pilot air screw your running it way too rich you need to look in your manual and find your screw then tighten it all the way but not too tight then turn it bout 2 1/2 time out the further out you turn it the richer it runs. That will fix your problem you might also want to use NGK BR8ECM spark plugs thats what fixed mine.

whats the top speed of a 2001 yz 125

ever since i got my bike last year ive wanted to know the top speed

i suggest jetting first and m

i suggest jetting first and maybe use 40:1 thats what i use. if all else fails it could be your crank case seals if they are stuffed gearbox oil can leak into the combustion chamber i had this problem with my old 95 yz125 a few years ago.

part of it is the bike

any 2 stroke that ur riding in trails and it isnt screaming is gonna do that although that is a high amount of spark plugs

but ur always gonna be filing them so get what u can done but always carry a couple of plugs around

have fun

i dont know why you are

i dont know why you are mixing 32:1 i mix 50:1 but i use thumper i found that it is a very nice mix it sound like you are running to much gas in it i am suprised it has not blown up yet

screaming? it dosent have to scream.

i actualy go a lot faster (on my yz250) by staying in a higher gear in lower rpms because there is less wheel spin and more traction and it is quieter, people dont understand that you dont have to rail your bike out to go fast. well atleast in trail riding

you should be running ngk9brs

you should be running ngk9brs plugs in your bike and make sure your not just putting around on your bike. 2stroke are ment 2 be ride like you stole them you will kill plugs if you dont ride hard on them and if you dont shake up your gas tank everytime you go too ride your bike because your oil will sit at the bottom of your tank if you dont.

fouling plugs

Well first off, make sure your running the hell outta that thing, 2 strokes are ment to be opened up!
try. 30:1. light trail riding can sometimes leave un-burnt deposits on ur plug. Run it a lil' harder. It worked for me!

YZ 125 Plug Foul

Buy some fully synthetic 2 stroke oil, all ur proplems will be solved. Yamalube is the wrost oil u can use.

Plenty of good advice above.

Plenty of good advice above. I would check the carby settings and jets. Plugs foul because they block up with unburnt oil residue so if your fuel/oil ratio is good then it could mean you aren't ringing the tits off it enough. Unless you ride like Stefan Merriman through the trails then I would say that this could be part of the problem. You can always lean out your mix to compensate for slower, lower revving trail riding.

Hayden

yz 125 fouled plugs

Yamalube is the worst oil you can use in your bike. It doesnt matter how you mix it 32:1 or even 40:1 it will foul you plugs. I recomend using a fully sinthetic oil like motul or Silkolene. Try these and youll be back to having fun on your bike, and dont forget to use a BR8 plug.