Choke Air mod

I've seen lots of old discussions on the "Choke Mod", but these are the first pictures I've seen that make it clear what hole is being talked about - I had deduced this was the hole, but these pictures make it clear. I've also not seen a clear explanation for the reason for the mod (though I have seen a number of folks saying it works well).

Is this mod restricting air to the engine, or getting the enrichment circuit to pull in more fuel?

In what kind of air temperatures is this mod most beneficial?

Hi,
Coming in on the end of this post, can someone please advise what the purpose of this mod is for ?

Thanks
Pete F
UK

www.kz1300.com/index.php/forum/carburato...-start-issue?start=0

In this thread Scotch theorizes that this port being reduced in size will allow the engine to start better by partly blocking this port you increase the vacuum in the carbs letting the bike start easier. I wish we had a before and after video for this mod.

I broke three drill bits trying to drill MIG tips so I've ordered some of the 280 jets that were recommended

I did the rivet body method. Granted it does not "look as professional", but no mods to the carbs and with epoxy holding them in I can remove them with a bit of heat. Chances are, no one will see them until I'm dead or too old to ride.

Plus, I had the rivets and epoxy on hand so took all of 5 minutes when the carbs were on the bench anyway.

zed thirteen wrote: "I broke three drill bits trying to drill MIG tips......"

MIG tips are a hard Brass. Best done on a drill-press so the feed can be controlled. No need to drill the entire tip 3/32". They can be first counter-bored with a more robust 1/8" drill - then use the 3/32" to complete the drilling.

Note: The MIG tip MUST be shortened as shown in the photos of one of the original posts !

My "Holley" jets should be here in the next day or two, and will post.