so close, idle, throttle trouble

[nozzlegoblin]

I've been fixing problem after problem on my Yamaha XJ750 Seca for weeks now, and I'm almost there. I balanced my carbs, and now my bike runs okay but when it gets warmed up the throttle seems to get stuck or just start revving really high. What do I need to adjust to fix this?
Thanks.

[Wrider]

Is it revving really high with the throttle shut or just when you rev it up then shut it off?
My first instinct is that your idle is way up or you're running a bit lean. Fuel/air mix screws turned out 2.5 turns? That's a good baseline to start at.

[nozzlegoblin]

When it is warming up, i take the choke off and it seems like it wants to die. I give it a little gas. after things start to seem okay, when I rev it a little, it starts to stick or just increase. it seems like i'm really hitting the gas but I'm not.

[Gummiente]

I'll second Wrider's guess that the carbs are set up too lean.

[storysunfolding]

Also a possible vaccum leak. Those little rubber caps you used for balancing often like to crack and let more air in. There are other rubber parts that crack too but I'm also for a lean condition just one caused by a different source

[nozzlegoblin]

Thanks for the help so far....
At risk of seeming like a moron, how does one resolve this too lean issue? From what I've read, too lean can really destroy things. These carbs are driving me crazy. just when I think I'm close, I find out that I'm further away. I want to take my bike for a ride but I'm afraid the thing is just gonna blow up. I can't find a leak but there is a hose going from the gas tank to the third vacuum valve, it is not clamped in place. It seems to just be held in place by the tension of the hose fitting snug over the nipples. (for lack of better words) Help!

[Wrider]

You can check for vacuum leaks while the bike is running by spraying the rubber parts with WD40. If there's a leak it'll rev up when you spray it or at least show bubbles.

The basic fix to lean/rich conditions is the fuel/air mix screw, make sure that's 2.5 turns out. If that doesn't work go with a pilot jet and main jet.

[nozzlegoblin]

Is there a valid reason why my Haynes manual say "do not attempt adjustment" referring to the mixture/pilot adjustment screw?

[Wrider]

Because according to the EPA you should never have to change that to make a vehicle run correctly.
Ignore the manual on this one and change it. We've had to do it merely because of altitude up here at 7900 feet with everything else bone stock.

[coffee_brake]

Because according to the EPA you should never have to change that to make a vehicle run correctly.
Ignore the manual on this one and change it. We've had to do it merely because of altitude up here at 7900 feet with everything else bone stock.

Amen. My Connie didn't run right till I hit Kansas, Ryan....