Frustrated to beat all hell!!

I took my carb to my buddy who is a Yamaha mechanic. He blew it out. I put new jets in... new throttle cable and slapped it back in. 2 turns out on the fuel screw. The bike won't idle right. Pops like crazy. No, it is not lean. 40/162.

We checked the carb again... perfect. No leaks in the pipe. The grey wire is not grounding. The CDI is good. The woodruff key is ok. Changed the plug. Fresh gas.

Could this popping be the plug wire maybe?

You jazz on this thing and decel sounds like a misfiring machine gun. HOLY SMOKES. :)

its not lean?? 40/162 sounds pretty lean to me :)

Check the carberator joint for leaks and the infamous "slide installed upside down". Something is causing a lean condition.

Check the carberator joint for leaks and the infamous "slide installed upside down". Something is causing a lean condition.

What he said.....check the pic's in the manual, to be certain the slide is in correctly. It sorta looks correct when it's fitted wrong :D Look in your manual, you'll see what I mean. :)

40/162 is 1 richer than I have ever run. I used to run 38/160 and it was a twitch lean in the mountains but ran good. I went richer for insurance.

My mechanic buddy thinks it is electrical.

Oh... when you kick it. It sometimes stops your leg dead... after the whole TDC... decompression a bit... back up and kick. It rarely did that in the past.

My buddy is at the shop... "definately not the slide."

He is going to "ohm some s&^% out." :)

Check the pj if the carb was blown out, you could have blown some junk into it. I would also check the cams. If the exhaust cam gets tight it could create a lean condition.

Check the pj if the carb was blown out, you could have blown some junk into it. I would also check the cams. If the exhaust cam gets tight it could create a lean condition.

PJ... clear...

Cam: Wouldn't that decrease compression? It has a ton of compression.

I could be wrong (wouildnt be the first time) but it sounds like you have an air leak. Forget about the electrics. Get a squirty bottle full off petrol and squirt it around the carb manifolds when the bike is idleing. When it stalls, you've found your leak. Also check that the hotstart circuit is working correctly.

My 03 wr450 was doing that same thing. Checked with Yamaha and they recomended 3 1/2 turns out on the idle mix and it worked.

I could be wrong (wouildnt be the first time) but it sounds like you have an air leak. Forget about the electrics. Get a squirty bottle full off petrol and squirt it around the carb manifolds when the bike is idleing. When it stalls, you've found your leak. Also check that the hotstart circuit is working correctly.

Checked both of those...

Did you try replacing your spark plug? As stupid as it sounds, it was the cause of a lot of running issues when I worked behind the parts counter for 10 years. It is also fairly cheap to try. Just a thought.

He found the problem.

I guess there was a stator wire by the tank that was frayed. :):D

Did you try replacing your spark plug? As stupid as it sounds, it was the cause of a lot of running issues when I worked behind the parts counter for 10 years. It is also fairly cheap to try. Just a thought.

Yes... and not change. One of the first things we did. I cannot believe how rusted the old plug was. :)

Check the metal plate on the slide...it goes on opposite from what it seems...I messed with this for three days before I figured out from the online pictures that it was upside down,,,,the bike wouldnt idle an poped like crazy....Its worth checking

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