Carb Issue?

[NF11624]

Hi,

I was just starting my bike back up after two weeks (of doing some mods), and I've ridden around some and I've noticed a very distinct change in behavior:

• On startup:  The bike revs on its own (to about 5k) for a second before settling down to usual choke RPMS, but the RPMs rise up faster than usual as well (such as going to 3-4k when the bike has only been running 30 seconds at 1/4 choke - not normal for me)
• Riding around:  There is a significant loss of engine braking due to RPMs dropping off slowly.  For instance, prior to the mods, pulling the clutch would almost instantly drop the RPMs to idle.  Now it takes several seconds to do so.

Of course, the mods I did were suspension mods, so I doubt this is where the problem is, otherwise the bike is stock.  Is this a carb issue, and if so what can I do about it?  Could some of the hoses be routed wrong?

I have a 2006 F model for reference.