Topic: Idle won't come down at stops . . .

[kawazacky]

So, here's a question. My CB650 is idling high. Really high - at 7000 rpm according to my tachometer, which probably means about 3500-4000 rpms, since my tach reads roughly twice what it should (550 tach on a 650 engine).

I checked the cable returns, and both the throttle cable and choke cable seem to be returning fine. I SUSPECTED a corroded cable, as the bike ran fine in September, before I left it in the backyard for a month due to a bad charging system.

However, if it's NOT a corroded cable, what else should I start looking at? What else could cause this? What could have happened to the bike while it sat in the back yard for a month?

[750goes]

Lubricate your linkages and check all the inlet manifold rubbers for integrity - they could be cracked or loose ??

[Sweep]

If you have push/pull cables then see if hitting the throttle in the opposite direction takes down the idle.

If this were a Norton I'd say you have a sticking carb slide.

[kawazacky]

It seemed, upon dissassembly today, that all linkages and inlets were OK. I'll know more the further I dig . . . Mike Nixon, who some of you may have dealt with, suggested that the piston carbs' castings are simply wearing out - which would NOT be cool.

[my78k]

carb boot airleaks?

[Badger 5]

I had that issue and I looked at the carbs and noticed one of the lock nuts had come loose.  I just retuned the carbs and it was good.

[kawazacky]

One of the lock nuts where? Inside the carb assembly? It seemed today, when I was tearing the bike apart, that the intake manifolds fit snugly . . .

[GoatBaSS]

I had the same prob on RED and I lowered the needles. Amazing. But I know not of your advanced space age 650!

[super pasty white guy]

I think he probably means the locknuts on the slides.  The ones that you loosen to do the carb balance.

dave

[Badger 5]

I think he probably means the locknuts on the slides.  The ones that you loosen to do the carb balance.

dave

bingo

[GoatBaSS]

Roger!