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My wife just bought an 87 Vulcan 750 and she has noticed that the bike revs at between 2 and 3K when it is hot. I asked my local shop why this might be and they suggested that the jets might be clogged costing around $200 - $300 in repairs. I am just curious what you folks think? Anyone have any ideas and if they are clogged would a cleaner in the fuel do the trick?

have you checked to make sure the choke isn't open?

Yes. That was the first thing I checked. She had been riding the bike for about ten minutes and was teaching me to ride when I noticed the revs were way up. We shut the bike off and let it cool but as soon as the engine heated up again the revs went up.

Sounds like the choke is stuck in the carb. Doesn't really matter if the lever isn't pulled. Try some carb cleaner or SeaFoam and report back.

If the bike revs up when its hot, it is usually a LEAN Condition. Check for air leaks and dry-rot around the intake manifold.
In general, if you rev up your bike at idle and the idle hangs, it is lean. If it bogs down and slowly returns to normal, it is rich.

We solved the problem. Another Vulcan rider told my wife about a little black knob just below the seat on the left that adjusts the RPMs. Sure enough she adjusted it and the bike now runs at around 1500 rpm. I don't know what this is called but for arguments sake I will call it a "needle valve". Anyone have any ideas about the name of this thing? Do all bikes have it?

Thanks to everyone who made suggestions.

idle adjustment knob

Does the bike have an owner's manual? If not, get one. If yes, read it.

Nope I just bought the bike so I haven't had the chance to go out and get one yet. But I will. Soon!

The idle is still a little high. Mine idles at little less than 1000 rpm. From time to time I do have to adjust the idle knob.

Thanks for the tip. I will check it.