Sweet!...........And your running no lid, right?.........[img]i/expressions/face-icon-small-wink.gif[/img]

Here's what I'd try with your set up;
Air/fuel screws (pilot screws) set at 2 3/4L and 3R turns out.
Stock pilot jets (22.5)
Stock needles in the 4th clip down.
Mikuni 160L/165R main jets.
Should run like a demon. Lets hope they didn't damage the motor by running it to too long too lean.
Now from here;
If you get a slight mid range bogg, try moving the needles to the 3rd clip.
If you feel ANY flat spot at top end, try going up to 165L/170R main jets (and if you do you will probably need the needles in the 3rd clip).
Give her a try and let us know.

 

Hi,I talked to a Yamaha guy and he says my plug should be white.Is that right?This thing is flying right like it is is it going to burn down?He says to leave it like it is.What do you think I should do?

 

Are my plugs supposed to be white?Do you think it is dialed in right?The mechanic says it is right on the money what do you think?It is running really fast.

 

If the plug is white at the tip (where the gap is) then you are lean. I never had much faith in dealers working on my quads. Do you know if this quads ever been rejetted? Does it pop or backfire after you rev the motor? I'd still take it apart and rejet it to my specs or if not just to see what they put in there.

 

Dude I am with you here I will tear it down tonight and let you know what I got OK.I dont trust the tec I would rather see for myself.I will be shure and let you know how I made out.I dont know much about the bike other than the guy lived on long island and rode it around with his little kids 50 cc.Are the plugs supposed to be white though?what should I look for in a plug?

 

Hey I didnt notice much poping when I was letting off but maybe some what does that mean?That it hasnt been jetted?

 

Depending on just how old the plug is, the porcelin (sp?) can be white but you want to look at the tip (again, where the gap is). It should have at least a light brown tint to it just not white white. If it runs as good as you say then obviously it had to be jetted otherwise it would run like sheit with a full pipe and open intake. Nonetheless, if it were mine I'd still take it apart just to see. I mean, you did buy it used and don't know a lot about it, right?

 

If I were to take a stock bike and install a pipe and K&N filter and just run it how would it run?I got it from a dealership in Long island.He said the guy rode it with his kids 50 cc.He traded it in on a Italian motor cycle.It is running crip through the whole power band to a point I wonder how much rpms will it turn?What is the red line on one?I will go down and check the plug.I appreciate your help on this.Thank you.

 

It would run hotter. It would pop and or backfire on decel. You would hit a big flat spot on top end (upper RPMs). The MaxxRPM of the 660 is 9000..............I think.

 

I like a nice dark tan, almost like a chocolate brown color look to the plugs on my 4 strokes. If your plug is snow white, I'd hate to see the top of your piston![img]i/expressions/face-icon-small-shocked.gif[/img]