Hey, I put a hole right in the top of the piston on my blaster.

I thought I had the jetting right, but my the last couple times I've checked the plug, was after my g/f had just been riding it around the yard, and she doesn't ride the powerband too hard, if at all, so I guess that's why it seemed fine. Well, last weekend we decided to ride out to slash X. It's a good 25 mile ride, and on the way back, on a long straight rode, my piston gave out. It definately got too hot, as the hole is right where the spark plug is, in the center of the puston, about the size of my pinky finger. The spark plug was blistered and white, and I'm thinking it was to lean on the fuel/air mixture, but I'm also getting around to making an oil injection block off kit too, before I put it back together. The Cylinder is perfectly fine, and I'm not going to have to get it bored. There is a little white rough-spot in the combustion chamber of the cylinder head, not bad at all. I've cleaned out the ports and everything really well, and am gonna clean up the head with some fine sand paper.

So, my question is, should I play with the jetting some? Move the clip on the needle one position? The Jetting is pretty much stock, I have a DG pipe/silencer, and a uni air filter, with the airbox lid off.

Thanks a lot for any help.

 

Not much room on a 2-smoke for error on jetting. You better richen up the mains a couple sizes until your plug darkens....otherwise, you will pop the cherry again.

 

Does "pretty much stock" mean that you have not jetted up for the pipe and air filter? If that's the case then yes, you should go up probably 2 sizes on the main then recheck the plug color...

 

well, I think it's a stock main jet, I havn't taken the carb apart to check that. It's easier to see that it has a pipe and filter, and I've had the quad a couple of months, I didn't add the aftermarket bolt ons, it came with them. Anywho, thanks a lot for the info....if the main is larger than stock, any other suggestions?

 

even though the cylinder isnt damaged you still need to get it honed.

 

Ok.
For one check which plug you are using. Blaster's use BR8ES. Anything hotter then that, and it will burn a hole in your piston, to cold and it won't fire right. Check to make sure you are using the right plug first. If it's a 9, then you just found your problem.

Stock jetting is 230 main, needle on 3'rd, and the pilot is 32.5. If you are using a aftermarket pipe and scilencer then you will defently need to re-jet. Also with the air box lid open you are adding ALOT more air then before.
The trouble with jetting is it's hard to get right on. Even tho sometimes it might seem fine, its really not. Expecially with a lean condition it may seem to work fine, and have alot of power but your engine is heating rapidly.

You probably won't need to adjust the needle clip any, but you will need to change out the other 2. Start with the main jet around 320-300 and work from there. Make sure you use a new plug and do some plug checks to make sure everything is fine. You will probably need to change the pilot to a 35.
As long as things are running smooth on the bottom end you don't need to be "as accurate" as the top end. However it is extremely important that your main jet isn't running lean or rich.

Jetting is everything and makes the most out of your motor. To much or to less can cause alot more trouble then it's worth. If you have any more questions regarding jetting, plug checks, or anything else blaster related, feel free to PM me

Shavo