Did the pilot jet=40, main jet=125, needle jet=N1TC, short snorkel=14073-1577, idle screw out 2 turns, FMF Q4 with power bomb.

Bike ran great for 15 minutes or so then acted like it was out of gas. Switched to Res. problem continued. Added gas same problem. Now bike won't idle, it dies, and needs lots of throttle to start.

Opened gas cap and problem persists. Gas is not the freshest.

Any suggestions?
Thanks, Stephen

 

Water in the gas???

Ride on
Brewster

 

Vacuum Leak

 

Having done CVK setups over and over and over and over.... and over. The fact that it ran perfect for 15 minutes is key. MOST any mistake you could have made while doing this work would show up the instant you started the bike. So..

Lets add it all up -
"Did the pilot jet=40, main jet=125, needle jet=N1TC, short snorkel=14073-1577, idle screw out 2 turns, FMF Q4 with power bomb.

Bike ran great for 15 minutes or so then acted like it was out of gas. Switched to Res. problem continued. Added gas same problem. Now bike won't idle, it dies, and needs lots of throttle to start.

Opened gas cap and problem persists. Gas is not the freshest."

Your new pilot jet got clogged with crap during the first 15 minutes of running - That is my opinion - If so, it'll have no ability to idle, no ability to fuel on startup without big throttle, and should run pretty well as long as RPM's are kept above pilot circuitry fueling ( I do not know exactly what that RPM would be because it depends on engine loading and throttle position..) AND, this is assuming the needle jet hasn't also become clogged, in which case high RPM fueling/running will also be affected..

If this is what has happened, the entire carb will have to be cleaned internally.. Let's hope you just have old watery gas in your bike - 10% ethanol gasoline doesn't keep fresh very long..

 

I would agree there is something stopping fuel flow.

Now does it run with choke? Can you get it to blip up and run with more open throttle? If so, the pilot circuit is clogged as some have mentioned. If not then quickly open the fuel drain and see if there is gas in the bowl.

If no fuel make sure all fuel lines are hooked up correctly without any pinches and, if it is a vacuum petcock the vacuum line is hooked up and not pinched or switched out with a fuel line. Make sure the breather lines aren't pinched When I took off my fuel tank the one fuel line was almost folded in half. I installed two short lines hooked to a 90° plastic vacuum line I got at an auto parts store.

Don't know where you are located, but in the hop ups I've seen it is recommended to start with 2.5 turns out and it works great at 900 ft elevation. Once the engine is running, for proper adjustment you turn the screw out until the idle drops, then turn it in until the idle drops again counting the turns, proper adjustment is half way between those two points. KLXter illustrated a great innovative way to do the adjustment if you have the stock mix screw, it was a bit of thick tubing over the end of a longer hex style blade screwdriver bit you'd use in a drill. Maybe with this comment he will post an image or link to the one posted before. Slick trick.

 

Here it is -

 

It seems water in the gas was the problem. The pilot jet looked fine, but I blew it out to be sure. Drained and flushed gas tank. Found water in gas removed. Put in non-ethanol and the bike runs great. Idle screw is now sensitive to adjustment. Due to weather I haven't gotten another 15 minute test ride. That will tell the story for sure.

Thanks for all the suggestions.
Stephen