If you are talking about the main jet, it is a Mikuni 127.5
The OEM stock # is 09491-25018
Suzuki wants ~$10 bucks for it but you can get them from any one who sells Mikuni parts for about $5-$7.
The large jet fits only the front carb, the small jet will fit either carb.
Large jet is Mikuni N100.604 Large Round Main Jet...size 127.5
Small jet is Mikuni N102.221 Small round Main Jet....size 127.5
The needle jet according to www.boulevardsuzuki.com is
a P-2M, stock# 09494-00892.
Runs about $25, but you should be able to find that cheaper as well.Edited by navigator on Mar 17, 2012 at 08:18 PM