Stealth13, on 03 February 2012 - 05:51 PM, said:

Stealth13, on 02 February 2012 - 07:29 AM, said:

whats your elevation?

and did you clean the pilot, or replace the pilot?

Just cleaned and elevation is whatever Calgary Alberta would be

Carb, huh? Didn't think it would be that but in a later post you mentioned you'd only ridden it once or twice since getting it so that makes sense, I guess.

When you say overheat after 5 minutes, what do you mean? Fluid dripping? Glowing head pipe? Explain as all anyone has is your words to go by.

After 5 minutes ir sp of idling your header will glow but you shouldn't have dripping coolant.

If its still stock jetted, which is lean from the factory no matter where you live altitude wise, read the Stickys at the top of the forum and rejet accordingly. Or you possibly could have moved the garbage from one place in the carb to another so it may need a full clean. Again, search on the forum for how to do that, it's been covered and you can seriously damage you carb if not done correctly. And put back together correctly as well.

You're on the right track, though. If its jetted right it will idle longer but it does need air moving over it.

Mike

We'll I rode the bike for an hour and it seemed ok for heat.

When I pull full throttle it stutters, what could this be? I have yZ throttle and grey wire mod

It is lean!!!!!! In your situation, just buy a JD Jet kit, install it, and live happily ever after.

Buy a good service manual and read it.

If they sit with gas in the carb for more than a month, the pilot jet will start to plug up. The main and other orifices may start to plug up, too. Use fuel stabilizer or drain the gas out using the allen screw on the bottom of the carb. And they come lean, stock, to meet emission tests. It all contributes to a lean condition, and you will have poor perfomance and possible engine damage unless you rejet and keep the carb clean.

I don't see how the Yamaha engineers would design a bike to damage itself by being too lean right from the factory ?

They didn't. The EPA did. Yamaha has to have it that lean from factory to pass regulations. 4 strokes can run lean w/o damage, unlike 2strokes. The bike isn't designed to sit still with motor running.

Calgary elevation is 3,348 ft.

Suggestions of pilot jet and/or running too lean make a lot of sense.....

So does getting a manual and doing some reading.

Also...have been lots of previous threads on hard starting and carb problems...try doing a search and reading thru a couple of threads....lots of helpful info.

Good Luck and don't forget your choke.