How high should it rev?

[jsandidge]

When first starting the bike on full choke, it revs up to around 4000. This seems high, so I immediately back down to about 3/4 choke. This drops the rpm's, but it surges a little bit at first. It will then smooth out once it's warm enough to back off the choke some more. I do have an exhaust leak at the back of the pre-muffler on one side. What is normal for rev's on choke?

[Brendan W]

There's no ecu backed injectors here
Seems pretty normal behaviour to me. I don't let it get to 4000 just push it in 1/2 way quick. Seems to depend on the day, how warm the air has been over the previous 12 hours or so. If the temp gauge in the garage is 16C/60F or above she'll likely want to rev high on full choke. Some days she'll even rev high on the 1/2 setting. She should be settled and running after two minutes or so. I have idle set a needle width below 1000. Once she's remotely warm-ish even a hour after a ride, full choke will kill a running motor almost as fast as the kill switch.
The exhaust leak will have some effect on balance maybe but it's not going to be major.
Normal fast idle for me can be a shade over 2000, at 1/2 choke. I don't hang around. Generally I'm on the bike starting and in gear and gone as soon as possible.

[Steve]

If you play a little bit more with the "choke" control, you will find a "happy spot" where the engine will start and run. Any less, it won't. Most of my bikes (my Wing, included) will start will a bit less than half "choke". At that setting, engine speed is in the 2000-2500 range. It makes me cringe to hear an engine fire up and start racing, so I try to keep it as low as I can. I have found the spot on my Wing's "choke" that allows me to start the engine and keep it well under 1500. Sounds really low, but when warm, it idles at 700, so it starts at double the warm idle speed, just like my GSes.

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[tkent02]

How much choke you need depends on the temperature, too much choke will always send it revving up. You shouldn't need full choke until the weather is in the full on winter mode, maybe 20 something degrees F? Maybe not even full choke then, it just depends, all of these old bikes are different.
Just pull it partway out, hit the starter and then pulll it out more and more until it fires. If the float bowl is full, it should start as soon as the choke gets to the proper point for the temperature. Then it won't rev up much.

Or,

Go full choke but kep a hand on the choke so you can modulate it as necessary to keep the RPM where you want it. You propbably need to disable the clutch danger switch to do this.

What Steve said is right, nothing is as hard on an engine as high RPM when it is still cold.

There is no reason to ever go above about 2,000 during a cold start.

[850 Combat]

Yours is acting fairly normal. Full choke on mine will get to about 3500 or so rpm pretty quickly.