plug chop?

Yamaha Raptor 350 & Warrior Forum

Help Support Yamaha Raptor 350 & Warrior Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

bickel76

Well-Known Member
Joined
Dec 26, 2005
Messages
780
Reaction score
0
you guys are probably gonna clown me, but what do you mean when you say plug chop? here in the very near future i am probably going to have to rejet my carb so right now i'm trying to get as much useful info i can find. while i'm asking, does anyone have an idea as to where i should start with the main jet size? all i have is pro design intake, holes in lid and pro circuit t4. also, i'm only about 400 ft above sea level.
 
one more stupid question. when you do the plug chop, should the engine be cold or hot. should i run it a little bit with the existing plug and then change it and do the plug chop or does it matter?
 
well i would say get it to operating temp... let it idle( this is how i checked my jetting) shut it off.. let it cool for a couple mins then pull the plug.. do an 1/8 throttle run in 1st or 2nd shut it off and pull the plug... do the same for 1/2 3/4 and full throttle but watch out.. if you are lean on the main you risk some problems if you prolong the use of it being lean.
 
why can't you just do it the one and easiest way! LOL!

You mean just do it wide open only? Then you only check the main jet, you need to use different throttle ranges to make sure your jetting is right all around.
 
Heres right from my manual on how to do a PLUG CHOP:
Step 1: Ride the ATV a short distance at full throttle in any gear.
Step 2: Push the engine stop switch to OFF before closing the throttle and simultaneously pull in the clutch or shift to neutral; coast and brake to a stop.
Step 3: Remove the spark plug and examine it.
And there are some other things that you should know about. If you are really worried just buy a Clyer service manual.
 
Like i said before, doing a full throttle run only tells you how your jetting is at full throttle. You could have you main jet perfect and still be way off on your idle and midrange, so you really need to do at least 3 chops before you can be sure your jetting is good.
 
one more stupid question. when you do the plug chop, should the engine be cold or hot. should i run it a little bit with the existing plug and then change it and do the plug chop or does it matter?

Let the motor warm up on your old plug and USE A NEW PLUG for the chop itself!
 
Back
Top