Low RPM knock

[sri]

Hi I just got a used 2004 GS500f with 1700 miles on it , it runs great except for the fact that it some time knocks and and even stalls (like 1 out 15 times) at around 1600-2100 RPM if I rev it up in neutral after starting it up from cold. The RPM falls about a 1000 counts at each knock.  The knocking goes away once the RPM is over 2500.

Is it just the cold start and may be the jets need to be cleaned?

Also it refuses to start without applying choke! even after standing i the sun for a while, is this normal?

Anyone who could please advice?

[The Buddha]

Choke might be needed at all times ... I sorta prefer to have choke on for all starts ... even warm ones cos otherwise you might never be able to start when its warm. I set it lean at idle and rich everywhere else ...
Now your knock ... is it a misfire ... you have an air leak in that case or of course the thing could be lean all by itself or have jets clogged ...
Cool.
Srinath.

[sri]

it sounds like it misses a detonation, but I dont know what could cause it to happen only at low revs,  I will adjust the mixture richer and see if it helps...

Sri

[Egaeus]

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