Why does my '84 Honda Magna V30 idle high after she warms up?

wow ok cylinder get hotter better fuel burn also faster fuel burn kind a like timing gets advanced

1300 rmp thats alot

is the choke closing all the way ?

choke off all the way ?

on all my bikes except my honda 84 sabre cause i got that one in pieces it was 700cc but i see 750 cc engine in it

all the carbs syncronised right ?

maybe 1 cylinder getting more fuel than the rest ?

you have good question

you got a good bike

Honda Magna V30

It could be a vacuum leak somewhere in your intake system. To troubleshoot it, run your engine until it warms up and the revs increase.Next, get a can of WD-40 and spray around all of the intake components with your engine running. If your idle slows down, and smoothes out, you've found where to begin looking! Check for loose or missing screws, nuts, bolts, and cracked or missing gaskets and hoses. This is a trick I learned while repairing aircraft years ago that has never gotten out of date!

That motorbike employs a carby layout general as consistent speed or CV for short. there's a rubber diaphragm on the actual of each carb which could become worse over the years and require alternative. Tuning of those carbs could desire to be carried out with the engine at comprehensive working temperature. Failure to accomplish that can consequence in the indicators you describe. the specific variety on your motorbike (you have 4 of 'em) is "32mm Keihin CV". Plug that right into a seek engine and you will locate diagrams and tuning information. A 4 carb setup may be complicated to nail in case you at the instant are not geared up / experienced at it. i'm not accustomed to that motorcycles ignition yet while it does use a mechanical strengthen mechanism for the spark it must be sticking in the completely stepped forward place. this will additionally produce your worry. chuffed analyzing on your wet day.

Try synchronizing the carbs then setting the idle.

find the idle adjuster screw on the carbs (a small thumb screw) and adjust it to 1000 -1200 rpm when hot - this can be don while it is idling

May be the previous owner over throttled it to compensate for a busted choke mechanism.