z400 high revving at idle

[400exrider720]

So my 04 z400 wouldn't start. I had a 440 kit in it, but checked and it was only making 40lbs. compression, so I switched back to a stock piston and head that I had around just to get it running. It looks like the 440 piston needs a new hone, and valves seated in the head. Anyway, after I swapped top-ends I had 80lbs. compression. That should be enough to get it running, but it won't start. I pop started it and it runs, but bogs when I hit the throttle, and then revs to the moon if I let it idle.

I know these carbs have a vacuum line, and I was wondering if that may be leaking, or maybe someone else has ideas. Thanks in advance.

[400exrider720]

Here's a pic of the quad

[rtrocket59]

Originally posted by 400exrider720
So my 04 z400 wouldn't start. I had a 440 kit in it, but checked and it was only making 40lbs. compression, so I switched back to a stock piston and head that I had around just to get it running. It looks like the 440 piston needs a new hone, and valves seated in the head. Anyway, after I swapped top-ends I had 80lbs. compression. That should be enough to get it running, but it won't start. I pop started it and it runs, but bogs when I hit the throttle, and then revs to the moon if I let it idle.

I know these carbs have a vacuum line, and I was wondering if that may be leaking, or maybe someone else has ideas. Thanks in advance.

This just happened to me today. Check if the throttle cable is being pulled somewhere and if that doesnt work adjust the cable looser.