TOPIC:

Ive got 1981 KZ550C2 LTD (Canada)
It has stock airbox, and a 4 in to 1 exhaust.
I rebuilt the carbs but was reading around and think I need to re jet for the exhaust. Currently the main is 92 and secondary is 32.
Would I only need to change the main jet? If so what size?

The bike currently is hard to start and bogs
down with throttle once its finally idling.

Thanks!
 

s3.amazonaws.com/gpzweb/TK22mainPage/TK22mainPage.html

The above link is a treasure trove of great information assembled by member loudhvx, our 550 guru.  In particular check out the page discussing jet kits.

Typically, if you keep the airbox the jetting changes for the bike brought on by a free flow exhaust are not profound.  It's pod filters, that many people also install, that are the real game changer when it comes to rejetting needs.

BTW, when posting photos it's important to click "insert all" before posting.  That way the photos show up in high resolution and are much easier to see compared to having to click the thumbnail image.

My wife has the same bike with stock exhaust.  It is notorious for taking a long time to warm up.  Needs the choke for at least ten minutes when starting cold.  But when it's finally warmed up...what a beautiful engine!

Thanks for the tip.

=11pxI drilled out the original #92 main jets to a #101.6, and removed the inline fuel filter.
=11pxThe bike runs a bit better. If I slowly increase the throttle I can get past the bogging down and to a point where I can get the =11pxrpms up. However at idle if I quickly give it throttle it will bog and die.
=11pxWould I need to upsized the secondary jets as well?
 

What is up with the (=11pxl)