Hanging up at 3000 rpm

[gfrisch]

My 2006 600 Katana is hanging up a bit at 3000 rpm before dropping to idle when I let off tje gas. My local dealer said it may be because up took in some water because it did start to happen when caught in the rain. They said to ride it a few days to let it dry out. Any other thoughts?

[maniac1886]

If it were me, I'd say you have a vacuum leak somewhere. A hangin and/or bouncy idle is indicative of a vacuum leak. That or a butterfly is sticking on gunk inside the carbs as it closes. I don't know how water in the fuel could make an idle hang. It does quite the opposite. Ur mechanic is smoking Crack.

[shpielers]

Wtf? Water?? Um....no....
Sounds like a small vac leak.

[arsenic]

Hey, you guys ever notice anytime you get "advice" from a dealership service center, it's the biggest load of shit you can imagine? It keeps getting worse. I don't know how they do it, I'm impressed. It takes commitment to be that wrong all the time.

Ur mechanic is smoking Crack.

I've tried that a time or two. Even with the help of free base cocaine, I'm not that clueless.

[gfrisch]

If its a vacume leak what's a way to cure it without a full carb cleaning?

[arsenic]

Find where it's leaking and make it stop leaking. It's very unlikely to be anything internal. Meaning a full rebuild isn't really going to help. Likely areas are the rubber intake boots on the head. The rubber boots on the airbox. A cracked vacuum hose, o-rings not being installed under the sync ports. It can leak anywhere though. It's difficult to pin point most of the time.

[rarva]

with the ike running on idle, you can try to find the vacuum leak spraying wd40 (for example) on the sensitive areas (one at a time) specified by arsenic... if idle changes when you spray on that spot, there's your vacuum leak.

Also, there's an interesting post http://www.mychinamoto.com/forums/sh...y-re-different
don't have the expertise to say if is valid or not... the guys here will surely disprove it or not.

[hjliucan]

Hello Page master and gang, I'm new to this site. I got a '97 Kat 600 last October. Powerful machine! Recently The humming sometimes become varying alternatively high and low. I was told it need to be synched. I ended up taking the carb apart and checked each individual carb on the assembly. found two of the synch port without o-ring. replacing the o-ring, the 3rd and 4th were synched quite readily. the 1st always has stronger vacuum than the 2nd and the rest. I tried to make adjustment, the idle goes way up to above 3000 rpm. no matter what I do, it won't come down. i have to increase the vacuum of 1st carb to lower the rpm. then I took it out for a ride, after about 10 min. the engine stalled and I have hard time to get it started. what may be the problem? many thanks in advance for helpful hints.

[clevelandmanwhore]

also to add what arsenic previously stated, check all three rubber vacuum caps on the sync ports on carbs 1 thru 3. I had a similiar issue with crazy idle. Those caps dry out and crack frequently. I had to replace mine late this past spring and viola! Problem went away.